Skip to main content
Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry logoLink to Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry
. 1972 May-Jun;76A(3):263–283. doi: 10.6028/jres.076A.029

Low Temperature Thermocouples: KP, “normal” silver, and copper versus Au-0.02 at% Fe and Au-0.07 at% Fe

Larry L Sparks **, Robert L Powell **
PMCID: PMC6706574  PMID: 34565862

Abstract

The Seebeck thermoelectric voltages of two dilute alloys of iron in gold, Au 0.02 at% Fe and Au-0.07 at% Fe, have been determined with respect to KP (a particular Ni-Cr alloy), “normal” silver, and copper in the temperature range from 4 to 280 K. The power series representation of these data, along with the calculated Seebeck coefficients and derivatives of the Seebeck coefficients, have been extrapolated to 0 K and are presented as a function of temperature. In addition to these reference data, seven different Au-0.07 at% Fe alloys were thermoelectrically intercompared in order to determine the variability in wires from different melts and from different manufacturers. The largest deviation found amounted to about 9 percent of the output of a KP versus Au-0.07 at% Fe thermocouple pair between 4 and 20 K. A more typical variation for this temperature range was 2 to 4 percent. Initial indications are that the reference data can be adjusted satisfactorily with data from spot calibrations on particular wires. The effect of heat treatment is illustrated by comparing our results to Rosenbaum’s data for annealed and unannealed specimens of both Au-Fe alloys.

Keywords: Cryogenics, gold alloy, liquid helium, liquid hydrogen, liquid nitrogen, thermocouples

1. Introduction

The increasing use of liquid hydrogen and liquid helium in the scientific and aerospace communities has created a demand for specialized thermometry below, say, 25 K. Ordinary thermocouple combinations are only marginally acceptable due to their low sensitivity in this range. Dilute alloys of noble metals and transition metals, however, do form thermoelements with relatively high temperature sensitivity below 25 K. Au-2.1 at% (atomic percent) Co is perhaps the best known of this type. Unfortunately, the Au-Co alloy forms a supersaturated solid solution; Co tends to migrate to the grain boundaries even at room temperature [1]1. This migration changes the thermoelectric properties and reduces the worth of this material as a thermoelement. Another family of alloys of this type are alloys of Fe in Au. These alloys are metallurgically stable and exhibit extremely useful thermoelectric properties at very low temperatures. Work recently completed at the National Bureau of Standards in Boulder has resulted in precise calibrations and intercomparisons of two of these alloys, Au-0.02 at% Fe and Au-0.07 at% Fe. Our primary emphasis has been directed to the latter alloy. A differential thermocouple made with either of these Au-Fe alloys as the negative element and copper, “normal” silver (Ag-0.37 at% Au), or KP2 as the positive element provides a usable sensitivity even below 4 K.

The fact that trace amounts of transition elements in noble metal solvents causes anomalous thermoelectric properties has been known for some time. Borelius [2, 3] and co-workers determined the thermoelectric sensitivity of many dilute alloys of copper, silver, gold, and platinum in 1932. The electrical resistivity and thermopower of these alloys are of interest because of the unusual electron scattering which must be present to cause the peculiar behavior. Much of the work done on dilute alloys has, therefore, been to understand the bulk transport properties involved. Development of the Au-Fe alloys for use in low temperature thermocouple thermometry didn’t really begin until after 1960 when Berman [4] tested Au-0.02 at% Fe for possible use in their thermal conductivity apparatus. Since that time others, including ourselves, have been drawn into the field in search of better thermometers for use in thermal conductivity measurement systems.

Several necessary thermoelectric properties have been determined for the Au-Fe alloys, e.g., reproducibility after repeated thermal cycling [5], behavior in a magnetic field [6], and the effect of heat treatment [7, 8]. The number of investigations concerning these properties is small and the conclusions could, therefore, be representative of particular materials rather than a general material. The consensus is, however, that sufficient information is available to establish the Au-Fe alloys as the most promising thermoelement available for use at very low temperatures.

The intent of our work is to provide a precise, full range calibration for several practical thermocouple combinations involving Au-Fe alloys and to present comparison data from different manufacturers, different melts, and different spools. It is hoped that the tabular data presented in this paper can be used as reference data.

Discussion of the procedures needed to adjust the reference data to individual thermocouples must be delayed. Further analysis of our data may make such information available. The brief discussion of figure 5 in the text is an indication of what we hope the more detailed analysis will show.

Figure 5.

Figure 5.

Comparison of Seebeck coefficients for KP versus Au-0.07 at% Fe7, 47 and the Seebeck coefficient for KP versus Au-0.07 at% Fe7 computed by applying dip test data to the KP versus Au-0.07 at% Fe47 data.

2. Experimental Procedure

A detailed description of the items in this section appears in NBS Monograph 124 [9]. The contents of this section will, therefore, be general and brief.

The cryostat used in the experimental work consists basically of two working chambers. One chamber is filled with a cryogen which serves as the reference temperature for the thermocouples while the second chamber is controlled to some selected higher temperature. The thermal insulation surrounding the two working chambers consists of various radiation shields, high vacuum, and finally a liquid nitrogen shield. This arrangement allows the reference temperature to be established with liquid helium (approximately 4 K), liquid hydrogen (approximately 20 K), or liquid nitrogen (approximately 75 K). In the course of a calibration the temperature ranges spanned using these reference temperatures are 4 to 25 K, 20 to 90 K, and 75 to 290 K. Figure 1 shows schematically how the thermocouple wires are situated in the system.

Figure 1.

Figure 1.

Schematic of electrical and thermal situation of wires in the thermocouple calibration system.

The temperature of the reference bath is determined with a platinum resistance thermometer (PRT) when either liquid hydrogen or liquid nitrogen are used as the reference cryogen. The vapor pressure of the liquid helium is used to determine the reference temperature when helium is used as the reference liquid. The variable temperature of the upper chamber is determined with a germanium resistance thermometer (GeRT) when the temperature is below 20 K and a PRT when the temperature is above 20 K. All PRT resistances are measured with a Mueller G2 bridge and all voltage readings are made on a potentiometer with a resolution of 0.01μV. All automatic temperature controllers are of in-house design. During the course of a one hour test the temperature difference between the variable and reference junctions of the thermocouples is held constant to within 5 mK.

3. Materials

The calibration system can accommodate up to 22 thermocouple test wires at one time. Two different sets of materials have been tested as part of the thermocouple thermometry program at NBS. The first set of materials contained only one Au-0.07 at% Fe wire and one Au-0.02 at% Fe wire. These two wires were thermoelectrically compared to KP, “normal” silver, and copper at a total of 68 different temperature gradients. The second set of wires to be tested contained seven different Au-0.07 at% Fe wires and one Au-0.02 at% Fe wire. In this calibration KP was compared to all of the Au-Fe specimens and the Au-0.07 at% Fe wires were intercompared. Table 1 contains additional information on the selection of samples used in both the first and second calibrations.

Table 1.

Specimens of Au-0.07 at% Fe and Au-0.02 at% Fe calibrated with the first and second sets of low temperature thermocouple materials

Alloy Specimen
number
Wire diameter (millimeters) Comments
Au-0.07 at% Fe… 5 0.152 Supplier 1
6 .152 1
7 .152 1
47 .152 1
10 .127 Supplier 2 Bar 1
11 .127 2 Bar 2
8 .254 2 Bar 1
Au-0.02 at% Fe… 45 .127 Supplier 2 Bar 1
12 .127 Supplier 2 Bar 2

The KP wires used in the first and second calibrations were adjacent lengths from the same spool; dip tests indicate that there is no observable difference between adjacent lengths of wire from this particular spool. These two lengths will be referred to as the same wire for the remainder of the paper. The primary variability between the first and second calibrations involving KP must, therefore, be attributed to differences in the Au-0.07 at% Fe wires.

One of the seven wires in the second set of materials had completely different properties than the remaining six specimens. Spectrographic analysis indicated about 0.45 at% Fe rather than 0.07 at% Fe. Data obtained for this wire are not considered in the remainder of this paper or listed in table 1.

A micrograph was made for Au-0.07 at% Fe47 used in the first calibration (subscripts indicate specimen number as in table 1). Rather large grains were observed to be preferentially oriented along the axis of the wire. The maximum grain size encountered was approximately 300 × 70 μm.

As indicated in table 1, several different melts from two companies are represented. An important part in establishing the usefulness of Au-Fe alloys as thermocouple materials is the degree of uniformity among melts and among different producers. The results presented in the next section indicate the spread or nonuniformity found in the specimens available to us at the time of testing.

4. Results

The range of thermal voltages obtained by comparing a single KP wire to the seven Au-0.07 at% Fe wires listed in table 1 is shown in figure 2. The band in this figure is determined by plotting data for the combinations having the highest and lowest output of the KP versus Au-0.07 at% Fe pairs tested. Since the band width in this figure results from different Au-0.07 at% Fe wire versus the same KP wire, the observed spread in the data must be due to variation in the Au-0.07 at% Fe materials. Thermoelectric differences among the seven Au-0.07 at% Fe specimens are made more clear when the contribution of the KP element is eliminated as in figure 3. The data in this figure represent experimentally determined differences among the Au-0.07 at% Fe specimens except for the specimen 5 versus specimen 47 curve which is calculated.3 The variations in the Au-0.07 at% Fe material are compared with the total output of the KP versus Au-0.07 at% Fe combination in table 2. Specimen 11 is used as the common Au-0.07 at% Fe wire in this table. The largest relative deviations are seen to be in the temperature range 4 K to 20 K; this is the same temperature range where the enhanced sensitivity is needed. Rosenbaum [7] compared different melts of Au-0.07 at% Fe from a single manufacturer and found voltage variations of 1.4 percent between 4.2 K and 77 K and 1.9 percent between 4.2 K and 273.2 K. These values appear reasonable when compared to the corresponding data for our wires given in table 2. It is interesting that wire 5 and wire 7, figure 3, are from the same company; within company variations are greater than intercompany variations for our limited selection of specimens. The general grouping in figure 3, however, indicates that the variation between wires 6 and 7 is more typical of the within company differences. The near identity of wires 10 and 11 is undoubtably fortuitous since wire 8 is from the same melt as wire 10.

Figure 2.

Figure 2.

Extremes of the thermoelectric voltage found in tests paring a single KP wire to seven different Au-0.07 at% Fe wires.

Figure 3. Experimentally determined thermoelectric differences between Au-0.07 at% Fe5 and the other six Au-0.07 at% Fe specimens.

Figure 3.

The numbers in parentheses represent the specimen numbers involved in the individual curves.

Table 2.

Voltage differences between Au-0.07 at% Fe11 and the remaining Au-0.07 at% Fe specimens and percentage variation of the thermoelectric voltage of each KP versus Au-0.07 at% Fe pair from the thermoelectric voltage of KP versus Au-0.07 at% Fe11

Au-0.07 at% Fe
Specimen
numbers
Temperature Range
4–20 K 4–75 K 4–280 K 20–75 K 20–280 K 75–280 K
ΔEμV ΔE/E×100(percent) ΔEμV ΔE/E×100(percent) ΔEμV ΔE/E×100(percent) ΔEμV ΔE/E×100(percent) ΔEμV ΔE/E×100(percent) ΔEμV ΔE/E×100(percent)
5 vs 11 15.99 6.3 55.31 4.7 84.07 1.6 39.32 4.2 68.08 1.3 28.76 0.7
11 vs 6 4.00 1.6 16.89 1.4 49.53 0.9 13.79 1.5 46.43 0.9 32.64 .8
11 vs 7 1.69 0.7 20.21 1.7 72.05 1.3 18.52 2.0 70.36 1.4 51.84 1.2
11 vs 10 0.07 .0 0.10 0.0 0.11 0.0 0.03 0.0 0.04 0.0 0.01 0.0
8 vs 11 3.13 1.2 .93 .1 16.19 .3 2.20 .2 19.32 .4 17.12 .4
47 vs 11 8.18 3.2 31.28 2.6 43.00 .8 23.10 2.5 34.82 .7 11.72 .3
Average… 5.51 2.2 20.79 1.8 44.16 .8 16.16 1.7 39.84 .8 23.68 .6

Figure 4 contains the Seebeck coefficients for the KP versus Au-0.07 at% Fe thermocouple pairs tested. The close grouping of specimens 6, 7, 8, 10, and 11 is apparent here as well as the outlying characteristics of specimen 5. Table 3 details the temperatures and sensitivities at the low temperature inflections. Figure 5 plots Seebeck coefficients for three KP versus Au-0.07 at% Fe pairs. The lower line plot in this figure is for the single KP versus Au-0.07 at% Fe47 from the first set of calibrations. The data for this KP versus Au-0.07 at% Fe combination has not been published, but it has been rather widely distributed. The data represented by the higher of the two line curves are for KP versus Au-0.07 at% Fe7. The third curve, represented by rectangles, results when the data for KP versus Au-0.07 at% Fe47 in this figure is adjusted by dip test data for a length of wire adjacent to specimen 7. The KP used in the dip tested thermocouple was from a different manufacturer than that used to determine KP versus Au-0.07 at% Fe47. A detailed thermoelectric comparison had been made earlier for the two KP materials involved; there was no observable difference when the temperature was below 80 K and above 80 K there was a linear divergence to about 10μV when the temperature was 280 K. The lined data result from two separate and complete calibrations in the thermocouple calibration apparatus. There was approximately a three year time lapse between the calibrations. The rectangular data, on the other hand, resulted when information obtained from a series of dip tests was used to adjust the lower lined data.

Figure 4.

Figure 4.

Calculated Seebeck coefficients for a single KP wire versus seven specimens of Au-0.07 at% Fe.

Table 3.

Temperatures and corresponding Seebeck coefficients for the low temperature inflection points in the KP versus Au-0.07 at% Fe data

Au-0.07 at% Fe Specimen number Low temperature maximum Low temperature minimum
T(K) S(μV/k) T(K) S(μV/k)
5 17.8 15.84 32.3 15.53
6 18.1 17.23 37.1 16.71
7 18.8 17.21 36.5 16.79
8 17.3 17.14 38.6 16.43
10 18.1 16.99 37.3 16.45
11 18.0 17.00 37.3 16.45
47 17.2 16.36 34.2 15.91
Average 17.9 16.82 36.2 16.32
Estimate of σ 0.54 0.53 2.2 0.45

Heat treatment of the Au-0.07 at% Fe material is critical as is shown in figure 6. The point curves by Rosenbaum [7] represent data from the same bar stock before and after annealing. The thermopower is enhanced by annealing as would be expected when physical defects are eliminated. The Seebeck coefficient for KP versus Au-0.07 at% Fe11 is shown as a line in this figure. Rosenbaum’s experimental data for KP versus Au-0.07 at% Fe extends down to about 1.3 K, while the lower limit for our experimental data is approximately 5 K. The Seebeck coefficients plotted in figure 7 represent data for KP versus specimens of Au-0.02 at% Fe used in the first and second calibrations and for Rosenbaum’s [7] annealed and hard worked specimens. Specimen 12, used in the second calibration, was annealed by the supplier while specimen 45, used in the first calibration, was annealed in-house at 350 °C for 20 minutes in air. It appears that the in-house anneal may have been more effective than the producer anneal on our specimen 12. Rosenbaum’s data for KP versus Au-0.02 at% Fe extends down to 0.437 K for the hard drawn specimen. Figures 8 and 9 are further comparisons of our results of those of Rosenbaum. In particular, copper versus Au-0.07 at% Fe11 is compared to Rosenbaum’s results [8] for copper versus annealed Au-0.07 at% Fe in figure 8 and copper versus Au-0.02 at% Fe45 is compared to Rosenbaum’s results for copper versus annealed Au-0.02 at% Fe in figure 9. Figures 10 and 11 show the Seebeck coefficients for copper and “normal” silver versus Au-0.07 at% Fe11 and Au-0.02 at% Fe45, respectively. The effect of KP in the thermoelectric circuit with the Au-Fe alloys is clear when the rapidly falling thermopowers in figure 10 are compared with the thermopowers shown in figure 4.

Figure 6.

Figure 6.

Comparison of Seebeck coefficients for KP versus Au-0.07 at% Fe in the annealed and unannealed state.

Figure 7.

Figure 7.

Comparison of Seebeck coefficients for KP versus Au-0.02 at% Fe in the annealed and unannealed state.

Figure 8.

Figure 8.

Seebeck coefficients for copper versus Au-0.07 at% Fe.

Figure 9.

Figure 9.

Seebeck coefficients for copper versus Au-0.02 at% Fe.

Figure 10.

Figure 10.

Seebeck coefficients for copper andnormalsilver versus Au-0.07 at% Fe11.

Figure 11.

Figure 11.

Seebeck coefficients for copper andnormalsilver versus Au-0.02 at% Fe45.

A modified Gram-Schmidt approximation [10, 11] was used to represent the experimental data. Details of the fitting procedure are discussed elsewhere [9]. In order to facilitate computer programming of the data the original orthonormal polynomials and the associated orthonormal polynomial coefficients have been recombined to give simple power series coefficients. The relationship between temperature in degrees kelvin and the Seebeck voltage in microvolts for thermocouple types KP, copper, and “normal” silver versus Au-0.02 at% Fe45 and Au-0.07 at% Fe11 are represented by

E(T)=Σn=1LBnTn.

The coefficients, Bn, for the above thermocouple combinations are listed in table 4. Tables 5 through 10 are tabular results of the power series representation for one degree intervals in temperature. The Seebeck coefficients and their derivatives are also given in these tables. The experimental basis for the data is 5 ⩽ T ⩽ 280 K. Any extension of the power series representation for T > 280 K is an extrapolation and all of the uncertainties inherent in such extensions of experimental data must apply. Extension of the data to T < 5 K is more acceptable since the constraint E = 0 μV when T = 0 K was used in the original fit.

Table 4.

Power series coefficients for thermocouple types KP versus Au-0.07 at% Fe, KP versus Au-0.02 at% Fe, copper versus Au-0.07 at% Fe, copper versus Au-0.02 at% Fe, normal silver versus Au-0.07 at% Fe, and normal silver versus Au-0.02 at% Fe.

Power series coefficients KP vs Au 7 Fe KP vs Au 2 Fe Cu vs Au 7 Fe Cu vs Au 2 Fe n. Ag vs Au 7 Fe n. Ag vs Au 2 Fe
B(l) 6.9864426367 7.2668579396 6.9819441789 7.2623594676 6.9616414011 7.2420566898
B(2) 9.0607276605 × 10−1 1.0692244345 8.4001378651 × 10−1 1.0031654569 8.1796982011 × 10−1 9.8112149062 × 10−1
B(3) −4.3469694773 × 10−2 −6.2220191022 × 10−2 −4.5417070202 × 10−2 −6.4167566583 × 10−2 −4.1183301479 × 10−2 −5.9933797876 × 10−2
B(4) 1.2468246660 × 10−3 1.9487031660 × 10−3 1.3796048892 × 10−3 2.0814833941 × 10−3 1.1332864853 × 10−3 1.8351649913 × 10−3
B(5) −2.3500537590 × 10−5 −3.8863862277 × 10−5 −2.7648679333 × 10−5 −4.3012004132 × 10−5 −2.0564116972 × 10−5 −3.5927441812 × 10−5
B(6) 3.0837610415 × 10−7 5.3284892976 × 10−7 3.8534874955 × 10−7 6.0982157678 × 10−7 2.6125849627 × 10−7 4.8573132442 × 10−7
B(7) −2.9032251684 × 10−9 −5.2094815173 × 10−9 −3.8382718939 × 10−9 −6.1445282582 × 10−9 −2.3898974345 × 10−9 −4.6961538119 × 10−9
B(8) 1.9881512159 × 10−11 3.6920742674 × 10−11 2.7684122233 × 10−11 4.4723352843 × 10−11 1.5931957622 × 10−11 3.2971188358 × 10−11
B(9) −9.9174829612 × 10−14 −1.9020522841 × 10−13 −1.4483161512 × 10−13 −2.3586201427 × 10−13 − 7.7417132540 × 10−14 −1.6844753253 × 10−13
B(10) 3.5645229362 × 10−16 7.0508285353 × 10−16 5.4390389051 × 10−16 8.9253445111 × 10−16 2.7100280116 × 10−16 6.1963336555 × 10−16
B(11) − 8.9864698504 × 10−19 −1.8317974022 × 10−18 −1.4282076268 × 10−18 −2.3613580435 × 10−18 −6.6485927163 × 10−19 −1.5980097000 × 10−18
B(12) 1.5071673023 × 10−21 3.1644035401 × 10−21 2.4882871621 × 10−21 4.1455233949 × 10−21 1.0835762248 × 10−21 2.7408124807 × 10−21
B(13) −1.5093916059 × 10−24 −3.2636069898 × 10−24 −2.5831198571 × 10−24 − 4.3373352305 × 10−24 −1.0525122333 × 10−24 −2.8067276336 × 10−24
B(14) 6.8264293980 × 10−28 1.5201593461 × 10−27 1.2089129004 × 10−27 2.0464292991 × 10−27 4.6057748723 × 10−28 1.2980938998 × 10−27

Table 5.

Thermocouple KP versus Au-0.07 at% Fe11 – thermoelectric voltage, Seebeck coefficient, and derivative of the Seebeck coefficient; E = f(T)

T E S dS/dT T E S dS/dT T E S dS/dT
K μV μV/K nV/K2 K μV μV/K nV/K2 K μV μV/K nV/K2
0 0.00 0.000 0.0 60 962.74 17.139 43.4 120 2065.91 19.513 31.8
1 7.85 8.673 1565.8 61 979.90 17.183 43.6 121 2085.44 19.545 31.5
2 17.27 10.127 1346.7 62 997.11 17.226 43.7 122 2105.00 19.576 31.2
3 28.04 11.375 1152.4 63 1014.36 17.270 43.7 123 2124.59 19.607 30.9
4 39.96 12.439 980.4 64 1031.65 17.314 43.7 124 2144.21 19.638 30.6
5 52.86 13.342 828.8 65 1048.99 17.358 43.7 125 2163.87 19.668 30.3
6 66.59 14.103 695.4 66 1066.36 17.401 43.7 126 2183.55 19.698 30.0
7 81.03 14.739 578.6 67 1083.79 17.445 43.6 127 2203.26 19.728 29.7
8 96.04 15.265 476.7 68 1101.25 17.489 43.5 128 2223.00 19.758 29.4
9 111.52 15.697 388.1 69 1118.76 17.532 43.4 129 2242.78 19.787 29.2
10 127.40 16.045 311.5 70 1136.32 17.575 43.3 130 2262.58 19.816 28.9
11 143.59 16.323 245.6 71 1153.92 17.619 43.2 131 2282.41 19.845 28.7
12 160.03 16.540 189.2 72 1171.56 17.662 43.1 132 2302.27 19.973 28.4
13 176.65 16.704 141.4 73 1189.24 17.705 42.9 133 2322.16 19.902 28.2
14 193.42 16.825 101.0 74 1206.96 17.748 42.8 134 2342.07 19.930 28.0
15 210.29 16.909 67.3 75 1224.73 17.790 42.7 135 2362.02 19.958 27.7
16 227.23 16.962 39.5 76 1242.55 17.833 42.6 136 2381.99 19.985 27.5
17 244.21 16.989 16.8 77 1260.40 17.875 42.4 137 2401.99 20.013 27.3
18 261.20 16.997 −1.4 78 1278.30 17.918 42.3 138 2422.01 20.040 27.1
19 278.19 16.988 −15.7 79 1296.24 17.960 42.2 139 2442.07 20.067 26.9
20 295.17 16.966 −26.6 80 1314.22 18.002 42.0 140 2462.15 20.094 26.7
21 312.12 16.935 −34.6 81 1332.24 18.044 41.9 141 2482.25 20.120 26.5
22 329.04 16.898 −40.1 82 1350.30 18.086 41.8 142 2502.39 20.147 26.3
23 345.92 16.856 −43.5 83 1368.41 18.128 41.6 143 2522.55 20.173 26.1
24 362.75 16.811 −45.1 84 1386.56 18.169 41.5 144 2542.73 20.199 26.0
25 379.54 16.766 −45.3 85 1404.75 18.211 41.3 145 2562.94 20.225 25.8
26 396.28 16.721 −44.2 86 1422.98 18.252 41.2 146 2583.18 20.250 25.6
27 412.98 16.678 −42.1 87 1441.25 18.293 41.0 147 2603.45 20.276 25.4
28 429.64 16.637 −39.2 88 1459.57 18.334 40.9 148 2623.73 20.301 25.3
29 446.26 16.600 −35.7 89 1477.92 18.375 40.7 149 2644.05 20.327 25.1
30 462.84 16.566 −31.8 90 1496.32 18.415 40.5 150 2664.39 20.352 24.9
31 479.39 16.536 −27.5 91 1514.75 18.456 40.3 151 2684.75 20.376 24.7
32 495.92 16.511 −23.0 92 1533.23 18.496 40.2 152 2705.14 20.401 24.6
33 512.42 16.490 −18.4 93 1551.74 18.536 40.0 153 2725.55 20.426 24.4
34 528.90 16.474 −13.8 94 1570.30 18.576 39.7 154 2745.99 20.450 24.2
35 545.37 16.463 −9.2 95 1588.89 18.615 39.5 155 2766.45 20.474 24.1
36 561.83 16.456 −4.7 96 1607.53 18.655 39.3 156 2786.94 20.498 23.9
37 578.28 16.453 −0.4 07 1626.20 18.694 39.1 157 2807.45 20.522 23.7
38 594.73 16.455 3.8 98 1644.92 18.733 38.8 158 2827.98 20.545 23.5
39 611.19 16.461 7.8 99 1663.67 18.772 38.5 159 2848.54 20.569 23.4
40 627.66 16.471 11.6 100 1682.46 18.810 38.3 160 2869.12 20.592 23.2
41 644.13 16.484 15.2 101 1701.29 18.848 38.0 161 2889.72 20.615 23.0
42 660.63 16.501 18.5 102 1720.16 18.886 37.7 162 2910.35 20.638 22.8
43 677.14 16.521 21.5 103 1739.06 18.924 37.4 163 2931.00 20.661 22.6
44 693.67 16.544 24.3 104 1758.00 18.961 37.1 164 2951.67 20.683 22.5
45 710.22 16.569 26.9 105 1776.98 18.998 36.8 165 2972.37 20.706 22.3
46 726.81 16.597 29.3 106 1796.00 19.035 36.5 166 2993.08 20.728 22.1
47 743.42 16.628 31.4 107 1815.05 19.071 36.2 167 3013.82 20.750 21.9
48 760.06 16.660 33.3 108 1834.14 19.107 35.8 168 3034.58 20.772 21.7
49 776.74 16.694 35.0 109 1853.27 19.143 35.5 169 3055.37 20.793 21.5
50 793.45 16.730 36.5 110 1872.43 19.178 35.2 170 3076.17 20.815 21.3
51 810.20 16.767 37.8 111 1891.62 19.213 34.8 171 3096.99 20.836 21.1
52 826.99 16.806 38.9 112 1910.85 19.248 34.5 172 3117.84 20.857 21.0
53 843.81 16.845 39.9 113 1930.12 19.282 34.2 173 3138.71 20.878 20.8
54 860.68 16.885 40.7 114 1949.42 19.316 33.8 174 3159.60 20.899 20.6
55 877.58 16.926 41.4 115 1968.75 19.350 33.5 175 3180.51 20.919 20.4
56 894.53 16.968 42.0 116 1988.12 19.383 33.2 176 3201.44 20.939 20.2
57 911.52 17.010 42.5 117 2007.52 19.416 32.8 177 3222.38 20.960 20.1
58 928.55 17.053 42.9 118 2026.95 19.449 32.5 178 3243.35 20.980 19.9
59 945.63 17.096 43.2 119 2046.41 19.481 32.2 179 3264.34 20.999 19.7
60 962.74 17.139 43.4 120 2065.91 19.513 31.8 180 3285.35 21.019 19.6
180 3285.35 21.019 19.6 240 4576.81 21.930 9.5
181 3306.38 21.038 19.4 241 4598.74 21.940 9.4
182 3327.43 21.058 19.2 242 4620.69 21.949 9.3
183 3348.50 21.077 19.1 243 4642.64 21.958 9.3
184 3369.58 21.096 18.9 244 4664.61 21.968 9.2
185 3390.69 21.115 18.8 245 4686.58 21.977 9.2
186 3411.81 21.133 18.6 246 4708.56 21.986 9.3
187 3432.96 21.152 18.5 247 4730.55 21.995 9.3
188 3454.12 21.171 18.4 248 4752.55 22.005 9.4
189 3475.30 21.189 18.3 249 4774.56 22.014 9.5
190 3496.49 21.207 18.1 250 4796.58 22.024 9.6
191 3517.71 21.225 18.0 251 4818.61 22.034 9.8
192 3538.94 21.243 17.9 252 4840.64 22.043 10.0
193 3560.20 21.261 17.8 253 4862.69 22.053 10.2
194 3581.47 21.279 17.7 254 4884.75 22.064 10.3
195 3602.75 21.296 17.6 255 4906.82 22.074 10.6
196 3624.06 21.314 17.5 256 4928.90 22.085 10.8
197 3645.38 21.331 17.4 257 4950.99 22.096 11.0
198 3666.72 21.348 17.3 258 4973.09 22.107 11.1
199 3688.08 21.366 17.2 259 4995.20 22.118 11.3
200 3709.45 21.383 17.1 260 5017.33 22.129 11.5
201 3730.84 21.400 17.0 261 5039.46 22.141 11.6
202 3752.25 21.417 16.9 262 5061.61 22.152 11.6
203 3773.68 21.434 16.8 263 5083.77 22.164 11.7
204 3795.12 21.450 16.7 264 5105.94 22.176 11.6
205 3816.58 21.467 16.5 265 5128.12 22.187 11.5
206 3838.05 21.483 16.4 266 5150.31 22.199 11.3
207 3859.54 21.500 16.3 267 5172.52 22.210 11.1
208 3881.05 21.516 16.2 268 5194.73 22.221 10.7
209 3902.58 21.532 16.0 269 5216.96 22.231 10.3
210 3924.12 21.548 15.9 270 5239.19 22.241 9.7
211 3945.67 21.564 15.8 271 5261.44 22.251 9.0
212 3967.24 21.580 15.6 272 5283.70 22.259 8.2
213 3988.83 21.595 15.4 273 5305.96 22.267 7.3
214 4010.43 21.610 15.3 274 5328.23 22.274 6.3
215 4032.05 21.626 15.1 275 5350.51 22.280 5.2
216 4053.69 21.641 14.9 276 5372.79 22.284 4.0
217 4075.33 21.655 14.7 277 5395.08 22.288 2.7
218 4097.00 21.670 14.5 278 5417.36 22.290 1.3
219 4118.67 21.684 14.3 279 5439.65 22.290 -0.1
220 4140.36 21.698 14.0 280 5461.94 22.289 -1.4
221 4162.07 21.712 13.8
222 4183.79 21.726 13.6
223 4205.52 21.739 13.3
224 4227.27 21.753 13.1
225 4249.03 21.766 12.8
226 4270.80 21.778 12.5
227 4292.58 21.791 12.3
228 4314.38 21.803 12.0
229 4336.19 21.815 11.8
230 4358.01 21.826 11.5
231 4379.84 21.838 11.3
232 4401.68 21.849 11.0
233 4423.54 21.860 10.8
234 4445.40 21.870 10.5
235 4467.28 21.881 10.3
236 4489.17 21.891 10.1
237 4511.06 21.901 9.9
238 4532.97 21.911 9.8
239 4554.88 21.921 9.6
240 4576.81 21.930 9.5

A detailed error analysis has been done for the thermocouple calibration system and is discussed in the previously mentioned monograph [9]. A similar analysis of the Au-Fe combinations result in the total uncertainties given in table 11. These uncertainties include random errors and estimates of systematic errors, but are exclusive of errors in the temperature scales used. Units for the thermocouple tables and functions are based on the “NBS as-maintained volt” [12]; the International Practical Temperature Scale, IPTS–68, [13, 14, 15] for temperature above 20 kelvin; and the NBS acoustical scale, P2–20 (1965), [16, 17] for temperatures between 4 and 20 kelvin.

Table 11.

Total uncertainties in thermocouple calibrations

Thermocouple combination Total uncertainty
4–20 K 20–75 K 75–280 K
KP vs Au·0.07 at% Fe  9.8 mK  11.3 mK  31.9 mK
KP vs Au·0.02 at% Fe  14.2  16.1  33.1
Cu vs Au·0.07 at% Fe  17.1  20.1  54.7
Cu vs Au·0.02 at% Fe  14.4  22.8  81.4
n.Ag vs Au·0.07 at% Fe  16.2  19.9  59.1
n.Ag vs Au·0.02 at% Fe  14.3  23.5  84.8

5. Discussion

It is apparent from figure 4 that the Au-0.07 at% Fe47 alloy, used in the first calibration, has a lower Seebeck coefficient than all but one of the specimens tested in the second calibration. A possible reason for the lower thermopower is suggested by comparison with Rosenbaum’s data in figure 6. The Seebeck coefficient for specimen 47 falls below that of Rosenbaum’s annealed sample results by 4.7 percent at 20 K. This is in the right direction and appears to be of a reasonable magnitude to be caused by underannealing or annealing at a high temperature in the presence of oxygen. Oxygen combines with iron which, in effect, removes the iron from the transport processes which are responsible for the high thermopower of the dilute alloys [18]. Regardless of the reason for the lower sensitivity the fact remains that specimen 47 should not be chosen to represent the alloy in light of the information from the specimens used in the second calibration. The data shown in figures 3 and 4 indicate that the specimens 8, 10, or 11 would have the general properties desired and have a sensitivity near the average of the materials tested. The choice among these three wires is rather arbitrary and perhaps unimportant since, in general, published tables must be adjusted to the particular thermocouple wires being used. The important consideration is that the published data can be adjusted to fit any particular working thermocouple of this type.

The “normal” silver and copper versus Au-0.07 at% Fe11 data presented in this paper were calculated since neither “normal” silver nor copper were included in the second calibration with Au-0.07 at% Fe11. The following relationships were used to arrive at “normal” silver and copper versus Au-0.07 at% Fe11:

E(Cu vs Au 7Fe47)E(KP vs Au 7Fe47)+E(KP vs Au 7Fe11)=E(Cu vs Au 7Fe11)
E(n.Ag vs Au 7Fe47)E(KP vs Au 7Fe47)+E(KP vs Au 7Fe11)=E(n.Ag vs Au 7Fe11)

The actual combination was accomplished by combining the power series coefficients, e.g.,

E(Cu vs Au 7Fe47)=A1+A2T+A3T2+EA+E(KP vs Au 7Fe11)=B1+B2T+B3T2+EBE(KP vs Au 7Fe47)=C1+C2T+C3T2+ECE(Cu vs Au 7Fe11)=(A1+B1C1)+(A2+B2C2)T+A3+B3C3)T2+¯

The uncertainty in the calculated tables will be the combination of uncertainties, e.g.,

σCu vs Au 7Fe11=[σ2(EA)+σ2(EB)+σ2(EC)]1/2.

The selection of the Au-0.02 at% Fe specimen to be reported in detail is not as difficult as was the Au-0.07 at% Fe, primarily because we have only two specimens to consider. Figures 7 and 9 indicate that our Au-0.02 at% Fe45 is probably nearer to the optimum anneal than is the later specimen 12. Specimen 45 was used in the first calibration and was compared directly to both copper and “normal” silver. This eliminates the need to combine coefficients and increase the uncertainty as was the case for Au-0.07 at% Fe.

Table 6.

Thermocouple KP versus Au-0.02 at% Fe45 – thermoelectric voltage, Seebeck coefficient, and derivative of the Seebeck coefficient; E = f(T)

T E S dS/dT T E S dS/dT T E S dS/dT
K μV μV/K nV/K2 K μV μV/K nV/K2 K μV μV/K nV/K2
0 0.00 0.000 0.0 60 808.49 13.053 55.5 120 1694.43 16.360 45.9
1 8.28 9.226 1787.8 61 821.57 13. 109 56.1 121 1710.81 16.406 45.6
2 18.34 10.856 1479.4 62 834.71 13.166 56.6 122 1727.24 16.452 45.2
3 29.89 12.198 1209.2 63 847.90 13.222 57.1 123 1743.72 16.497 44.9
4 42.65 13.286 973.4 64 861.15 13.280 57.5 124 1760.24 16.541 44.6
5 56.39 14.155 768.6 65 874.46 13.337 57.8 125 1776.80 16.586 44.2
6 70.90 14.833 591.6 66 887.83 13.395 58.0 126 1793.41 16.630 43.9
7 86.00 15.346 439.4 67 901.25 13.453 58.2 127 1810.06 16.674 43.6
8 101.55 15.719 309.3 68 914.73 13.512 58.4 128 1826.75 16.717 43.4
9 117.40 15.972 199.1 69 928.27 13.570 58.5 129 1843.49 16.760 43.1
10 133.46 16.123 106.3 70 941.87 13.629 58.6 130 1860.27 16.803 42.8
11 149.62 16.189 29.1 71 955.53 13.687 58.6 131 1877.10 16.846 42.6
12 165.81 16.186 −34.4 72 969.25 13.746 58.7 132 1893.97 16.888 42.4
13 181.97 16.125 −85.9 73 983.02 13.805 58.7 133 1910.88 16.931 42.1
14 198.04 16.017 −126.9 74 996.86 13.863 58.8 134 1927.83 16.973 41.9
15 213.99 15.874 −158.7 75 1010.75 13.922 58.8 135 1944.82 17.015 41.7
16 229.78 15.703 −182.5 76 1024.70 13.981 58.8 136 1961.86 17.056 41.5
17 245.39 15.511 −199.5 77 1038.71 14.040 58.7 137 1978.93 17.098 41.3
18 260.80 15.306 −210.6 78 1052.78 14.098 58.7 138 1996.05 17. 139 41.1
19 276.00 15.091 −216.7 79 1066.91 14.157 58.7 139 2013.21 17.180 40.9
20 290.98 14.874 −218.6 80 1081.09 14.216 58.6 140 2030.41 17.221 40.8
21 305.75 14.656 −216.9 81 1095.34 14.274 58.6 141 2047.65 17.261 40.6
22 320.29 14.441 −212.4 82 1109.64 14.333 58.5 142 2064.93 17.302 40.4
23 334.63 14.231 −205.5 83 1124.00 14.391 58.4 143 2082.26 17.342 40.2
24 348.76 14.030 −196.7 84 1138.42 14.450 58.3 144 2099.62 17.382 40.0
25 362.69 13.839 −186.5 85 1152.90 14.508 58.2 145 2117.02 17.422 39.9
26 376.44 13.658 −175.2 86 1167.44 14.566 58.1 146 2134.46 17.462 39.7
27 390.01 13.488 −163.1 87 1 182.04 14.624 57.9 147 2151.94 17.502 39.5
28 403.42 13.332 −150.5 88 1196.69 14.682 57.8 148 2169.47 17.541 39.3
29 416.68 13.188 −137.6 89 1211.40 14.740 57.6 149 2187.03 17.580 39.1
30 429.80 13.057 −124.6 90 1226.17 14.797 57.4 150 2204.63 17.619 38.9
31 442.80 12.938 −111.7 91 1240.99 14.854 57.2 151 2222.26 17.658 38.7
32 455.68 12.833 −99.0 92 1255.88 14.911 56.9 152 2239.94 17.696 38.5
33 468.47 12.740 −86.7 93 1270.82 14.968 56.7 153 2257.66 17.735 38.2
34 481.17 12.659 −74.8 94 1285.81 15.025 56.4 154 2275.41 17.773 38.0
35 493.79 12.590 −63.4 95 1300.87 15.081 56.1 155 2293.20 17.811 37.8
36 506.35 12.533 −52.5 96 1315.97 15.137 55.8 156 2311.03 17.848 37.5
37 518.86 12.485 −42.2 97 1331.14 15.193 55.5 157 2328.90 17.886 37.3
38 531.33 12.448 −32.5 98 1346.36 15.248 55.1 158 2346.80 17.923 37.0
39 543.76 12.420 −23.4 99 1361.63 15.303 54.8 159 2364.75 17.960 36.7
40 556. 17 12.401 −15.0 100 1376.97 15.357 54.4 160 2382.72 17.996 36.5
41 568.56 12.390 −7.1 101 1392.35 15.412 54.0 161 2400.74 18.033 36.2
42 580.95 12.386 0.1 102 1407.79 15.465 53.6 162 2418.79 18.069 35.9
4 3 593.34 12.390 6.7 103 1423.28 15.519 53.2 163 2436.88 18.105 35.6
44 605.73 12.400 12.8 104 1438.83 15.572 52.8 164 2455.00 18.140 35.3
45 618.14 12.415 18.3 105 1454.42 15.624 52.3 165 2473.16 18.175 35.0
46 630.56 12.436 23.4 106 1470.07 15.676 51.9 166 2491.35 18.210 34.7
47 643.01 12.462 27.9 107 1485.78 15.728 51.5 167 2509.58 18.245 34.4
48 655.49 12.492 31.9 108 1501.53 15.779 51.0 168 2527.84 18.279 34.1
49 668.00 12.526 35.6 109 1517.34 15.830 50.6 169 2546.13 18.313 33.8
50 680.54 12.563 38.8 110 1533.19 15.881 50.1 170 2564.46 18.346 33.5
51 693.12 12.603 41.7 111 1549.10 15.930 49.7 171 2582.83 18.380 33.2
52 705.75 12.646 44.2 112 1565.05 15.980 49.2 172 2601.22 18.413 32.9
53 718.42 12.691 46.4 113 1581.06 16.029 48.8 173 2619.65 18.445 32.6
54 731.13 12.739 48.3 114 1597.11 16.078 48.4 174 2638.11 18.478 32.3
55 743.90 12.788 50.0 115 1613.21 16.126 47.9 175 2656.61 18.510 32.0
56 756.71 12.839 51.5 116 1629.36 16.173 47.5 176 2675.13 18.542 31.7
57 769.57 12.891 52.7 117 1645.56 16.221 47.1 177 2693.69 18.573 31.4
58 782.49 12.044 53.8 118 1661.80 16.268 46.7 178 2712.28 18.605 31.1
59 795.46 12.998 54.7 119 1678.09 16.314 46.3 179 2730.90 18.636 30.8
60 808.49 13.053 55.5 120 1694.43 16.360 45.9 180 2749.55 18.666 30.6
180 2749.55 18.666 30.6 240 3918.02 20.167 19.1
181 2768.23 18.697 30.3 241 3938.19 20.186 19.0
182 2786.94 18.727 30.1 242 3958.39 20.205 19.0
183 2805.69 18.757 29.9 243 3978.60 20.224 19.0
184 2824.46 18.787 29.6 244 3998.84 20.243 19.0
185 2843.26 18.816 29.4 245 4019.09 20.262 18.9
186 2862.09 18.845 29.2 246 4039.36 20.281 19.0
187 2880.95 18.875 29.0 247 4059.65 20.299 19.0
188 2899.84 18.903 28.8 248 4079.96 20.318 19.0
189 2918.76 18.932 28.6 249 4100.29 20.337 18.9
190 2937.70 18.961 28.5 250 4120.63 20.356 18.9
191 2956.68 18.989 28.3 251 4141.00 20.375 18.9
192 2975.68 19.017 28.2 252 4161.38 20.394 18.8
193 2994.71 19.046 28.0 253 4181.79 20.413 18.7
194 3013.77 19.073 27.9 254 4202.21 20.431 18.5
195 3032.86 19.101 27.7 255 4222.65 20.450 18.3
196 3051.98 19.129 27.6 256 4243.11 20.468 18.1
197 3071.12 19.156 27.5 257 4263.59 20.486 17.7
198 3090.29 19.184 27.4 258 4284.08 20.503 17.4
199 3109.49 19.211 27.2 259 4304.59 20.521 16.9
200 3128.71 19.238 27.1 260 4325.12 20.537 16.4
201 3147.96 19.265 27.0 261 4345.67 20.553 15.9
202 3167.24 19.292 26.9 262 4366.23 20.569 15.2
203 3186.55 19.319 26.7 263 4386.80 20.584 14.6
204 3205.88 19.346 26.6 264 4407.40 20.598 13.9
205 3225.24 19.372 26.5 265 4428.00 20.612 13.2
206 3244.62 19.399 26.3 266 4448.62 20.625 12.6
207 3264.04 19.425 26.2 267 4469.25 20.637 12.0
208 3283.47 19.451 26.0 268 4489.89 20.649 11.5
209 3302.94 19.477 25.9 269 4510.55 20.660 11.2
210 3322.43 19.503 25.7 270 4531.21 20.671 11.1
211 3341.94 19.529 25.5 271 4551.89 20.682 11.4
212 3361.49 19.554 25.3 272 4572.58 20.694 12.0
213 3381.05 19.579 25.1 273 4593.28 20.706 13.2
214 3400.64 19.604 24.9 2 74 4613.99 20.721 15.1
215 3420.26 19.629 24.7 275 4634.72 20.737 17.8
216 3439.90 19.653 24.4 276 4655.47 20.757 21.5
217 3459.57 19.678 24.2 277 4676.23 20.780 26.5
218 3479.26 19.702 23.9 278 4697.03 20.810 33.0
219 3498.97 19.726 23.7 279 4717.86 20.847 41.2
220 3518.71 19.749 23.4 280 4738.72 20.893 51.5
221 3538.47 19.772 23.1
222 3558.25 19.795 22.9
223 3578.06 19.818 22.6
224 3597.89 19.841 22.3
225 3617.74 19.863 22.0
226 3637.62 19.885 21.7
227 3657.51 19.906 21.5
228 3677.43 19.928 21.2
229 3697.37 19.949 20.9
230 3717.32 19.969 20.7
231 3737.30 19.990 20.4
232 3757.30 20.010 20.2
233 3 777.32 20.030 20.0
234 3797.37 20.050 19.8
235 3817.43 20.070 19.6
236 3837.51 20.090 19.5
237 3857.60 20.109 19.4
238 3877.72 20.128 19.2
239 3897.86 20.148 19.2
240 3918.02 20.167 19.1

Table 7.

Thermocouple copper versus Au-0.07 at% Fe11 – thermoelectric voltage, Seebeck coefficient, and derivative of the Seebeck coefficient; E = f(T)

T E S dS/dT T E S dS/dT T E S dS/dT
K μV μV/K nV/K2 K μV μV/K nV/K2 K μV μV/K nV/K2
0 0.00 0.000 0.0 60 719.52 9.331 −81.7 120 1162.03 5.835 −41.8
1 7.78 8.531 1423.5 61 728.81 9.250 −80.9 121 1167.85 5.793 −41.4
2 16.98 9.839 1197.0 62 738.02 9.169 −80.1 122 1173.62 5.752 −41.1
3 27.38 10.934 997.5 63 747.15 9.089 −79.3 123 1179.35 5.711 −40.7
4 38.79 11.842 822.3 64 756.20 9.010 −78.5 124 1185.04 5.671 −40.3
5 51.01 12.586 669.0 65 765.17 8.932 −77.7 125 1190.69 5.630 −40.0
6 63.91 13.187 535.4 66 774.07 8.855 −76.9 126 1196.30 5. 591 −39.6
7 77.35 13.663 419.3 67 782.88 8.778 −76.1 127 1201.87 5.551 −39.2
8 91.20 14.030 318.9 68 791.62 8.703 −75.2 128 1207.41 5. 512 −38.8
9 105.38 14.305 232.5 69 800.29 8.628 −74.4 129 1212.90 5.474 −38.5
10 119.78 14.500 158.5 70 808.88 8.554 −73.5 130 1218.35 5.435 −38.1
11 134.35 14.626 05.5 71 817.40 8.481 −72.6 131 1223.77 5.397 −37.7
12 149.02 14.694 42.3 72 825.84 8.409 −71.7 132 1229.15 5.360 −37.3
13 163.72 14.713 −2.4 73 834.22 8.338 −70.7 133 1234.49 5.323 −36.9
14 178.43 14.692 −39.5 74 842.52 8.267 −69.8 134 1239.79 5.286 −36.5
15 193.10 14.636 −70.0 75 850.75 8.198 −68.9 135 1245.06 5.250 −36.1
16 207.69 14.553 −94.8 76 858.92 8.130 −67.9 136 1250.29 5.214 −35.7
17 222.20 14.448 −114.7 77 867.01 8.062 −67.0 137 1255.49 5. 178 −35.3
18 236.58 14.326 −130.2 78 875.04 7.996 −66.0 138 1260.65 5. 143 −34.9
19 250.84 14.189 −142.1 79 883.00 7.930 −65.1 139 1265.78 5. 109 −34.6
20 264.96 14.042 −150.8 80 890.90 7.866 −64.2 140 1270.87 5.074 −34.2
21 278.92 13.888 −156.P 81 898.73 7.802 −63.3 141 1275.92 5.040 −33.8
22 292.73 13.729 −160.8 82 906.51 7.739 −62.3 142 1280.95 5.007 −33.4
23 306.38 13.567 −162.8 83 914.21 7.677 — 61.4 143 1285.94 4.973 −33.1
24 319.87 13.404 −163.2 84 921.86 7.616 −60.6 144 1290.89 4.940 −32.7
25 333.19 13.241 −162.4 85 929.45 7.556 −59.7 145 1295.82 4.908 −32.4
26 346.35 13.080 −160.7 86 936.97 7.497 −58.9 146 1300.71 4.876 −32.0
27 359.35 12.920 −158.1 87 944.44 7.438 −58.0 147 1305.57 4.844 −31.7
28 372.19 12.764 −155.0 88 951.85 7.381 −57.2 148 1310.40 4.812 −31.4
29 384.88 12.610 −151.5 89 959.20 7.324 −56.5 149 1315.20 4.781 −31.1
30 397.41 12.461 −147.6 90 966.50 7.268 −55.7 150 1319.96 4.750 −30.8
31 409.80 12.315 −143.6 91 973.74 7.212 −55.0 151 1324.70 4.720 −30.5
32 422.04 12.173 −139.5 92 980.92 7.158 −54.3 152 1329.40 4.689 −30.2
33 434.15 12.036 −135.4 93 988.05 7.104 −53.6 153 1334.07 4.659 −29.9
34 446.12 11.903 −131.4 94 995.13 7.051 −52.9 154 1338.72 4.629 −29.7
35 457.96 11.773 −127.4 95 1002.15 6.998 −52.3 155 1343.33 4.600 −29.4
36 469.67 11.648 −123.6 96 1009.13 6.946 −51.7 156 1347.92 4.571 −29.2
37 481.25 11.526 −120.0 97 1016.05 6.894 −51.1 157 1352.47 4.542 −28.9
38 492.72 11.408 −116.6 98 1022.92 6.844 −50.6 158 1357.00 4.513 −28.7
39 504.07 11.293 −113.4 99 1029.73 6.793 −50.0 159 1361.50 4.484 −28.5
40 515.31 11.181 −110.3 100 1036.50 6.744 −49.5 160 1365.97 4.456 −28.3
41 526.43 11.072 −107.6 101 1043.22 6.694 −49.0 161 1370.41 4.427 −28.1
42 537.45 10.966 −105.0 102 1049.89 6.645 −48.6 162 1374.82 4.399 −27.9
43 548.36 10.862 −102.6 103 1056.51 6.597 −48.1 163 1379.21 4.372 −27.8
44 559.17 10.760 −100.4 104 1063.09 6.549 −47.7 164 1383.57 4.344 −27.6
45 569.89 10.661 −98.4 105 1069.61 6.502 −47.3 165 1387.90 4.316 −27.4
46 580.50 10.564 −96.6 106 1076.09 6.455 −46.8 166 1392.20 4.289 −27.2
47 591.01 10.468 −94.9 107 1082.52 6.408 −46.5 167 1396.48 4.262 −27.1
48 601.43 10.374 −93.4 108 1088.90 6.362 −46.1 168 1400.72 4.235 −26.9
49 611.76 10.281 −92.0 109 1095.24 6.316 −45.7 169 1404.95 4.208 −26.8
50 622.00 10.190 −90.8 110 1101.54 6.270 −45.3 170 1409.14 4.181 −26.6
51 632.14 10.099 −89.6 111 1107.78 6.225 −45.0 171 1413.31 4.155 −26.5
52 642.20 10.010 −88.5 112 1113.99 6. 180 −44.6 172 1417.45 4.128 −26.3
53 652.16 9.922 −87.5 113 1120.15 6. 136 −44.2 173 1421.57 4.102 −26.2
54 662.04 9.835 −86.6 114 1126.26 6.092 −43.9 174 1425.66 4.076 −26.0
55 671.83 9.749 −85.7 115 1132.33 6.048 −43.5 175 1429.72 4.050 −25.8
56 681.54 9.664 −84.8 116 1138.36 6.005 −43.2 176 1433.76 4.025 −25.7
57 691. 16 9.579 −84.0 117 1144.34 5.962 −42.9 177 1437.77 3.999 −25.5
58 700.70 9.496 −83.2 118 1150.28 5.919 −42.5 178 1441.75 3.974 −25.3
59 710.15 9.413 −82.5 119 1156.18 5.877 −42.2 179 1445.71 3.948 −25.1
60 719.52 9.331 −81.7 120 1162.03 5.835 −41.8 180 1449.65 3.923 −24.9
180 1449.65 3.923 −24.9 240 1647.73 2.752 −17.3
181 1453.56 3.898 −24.7 241 1650.47 2.735 −17.1
182 1457.45 3.874 −24.5 242 1653.20 2.718 −16.9
183 1461.31 3.849 −24.3 243 1655.90 2.701 −16.6
184 1465.15 3.825 −24.1 244 1658.60 2.684 −16.3
185 1468.96 3.801 −23.9 245 1661.27 2.668 −16.0
186 1472.75 3.777 −23.6 246 1663.93 2.653 −15.6
187 1476.51 3.754 −23.4 247 1666.58 2.637 −15.2
188 1480.26 3.731 −23.2 248 1669.21 2.622 −14.8
189 1483.98 3.708 −22.9 249 1671.82 2.607 −14.4
190 1487.67 3.685 −22.7 250 1674.42 2.593 −14.0
191 1491.35 3.662 −22.4 251 1677.01 2.579 −13.6
192 1495.00 3.640 −22.1 252 1679.58 2.566 −13.1
193 1498.63 3.618 −21.9 253 1682.14 2.553 −12.7
194 1502.23 3.596 −21.6 254 1684.69 2.541 −12.3
195 1505.82 3.575 −21.3 255 1687.22 2.528 −12.0
196 1509.38 3.554 −21.1 256 1689.75 2.517 −11.6
197 1512.93 3.533 −20.8 257 1692.26 2.505 −11.3
198 1516.45 3.512 −20.5 258 1694.76 2.494 −11.0
199 1519.95 3.492 −20.3 259 1697.25 2.483 −10.8
200 1523.43 3.472 −20.0 260 1699.72 2.472 −10.7
201 1526.89 3.452 −19.7 261 1702.19 2.462 −10.6
202 1530.33 3.432 −19.5 262 1704.65 2.451 −10.5
203 1533.76 3.413 −19.3 263 1707.09 2.441 −10.5
204 1537.16 3.394 −19.0 264 1709.53 2.430 −10.6
205 1540.54 3.375 −18.8 265 1711.95 2.419 −10.8
206 1543.91 3.356 −18.6 266 1714.37 2.409 −10.9
207 1547.26 3.337 −18.4 267 1716.77 2.398 −11.1
208 1550.58 3.319 −18.3 268 1719.16 2.386 −11.3
209 1553.89 3.301 −18.1 269 1721.54 2.375 −11.5
210 1557.19 3.283 −18.0 270 1723.91 2.363 −11.6
211 1560.46 3.265 −17.8 271 1726.27 2.352 −11.6
212 1563.72 3.247 −17.7 272 1728.62 2.340 −11.5
213 1566.95 3.229 −17.6 273 1730.95 2.329 −11.1
214 1570.17 3.212 −17.6 274 1733.27 2.318 −10.4
215 1573.38 3.194 −17.5 275 1735.59 2.308 −9.3
216 1576.56 3.177 −17.5 276 1737.89 2.300 −7.6
217 1579.73 3.159 −17.4 277 1740.19 2.293 −5.2
218 1582.88 3.142 −17.4 278 1742.48 2.290 −2.1
219 1586.01 3.125 −17.4 279 1744.77 2.289 2.1
220 1589.13 3.107 −17.5 280 1747.06 2.294 7.6
221 1592.23 3.090 −17.5
222 1595.31 3.072 −17.5
223 1598.37 3.055 −17.6
224 1601.42 3.037 −17.6
225 1604.45 3.019 −17.7
226 1607.46 3.002 −17.7
227 1610.45 2.084 −17.8
228 1613.42 2.966 −17.9
229 1616.38 2.948 −17.9
230 1619.32 2.930 −18.0
231 1622.24 2.912 −18.0
232 1625.15 2.894 −18.0
233 1628.03 2.876 −18.0
234 1630.90 2.858 −18.0
235 1633.75 2.840 −17.9
236 1636.58 2.822 −17.9
237 1639.39 2.805 −17.8
238 1642.19 2.787 −17.7
239 1644.97 2.769 −17.5
240 1647.73 2.752 −17.3

Table 8.

Thermocouple copper versus Au-0.02 at% Fe45 – thermoelectric voltage, Seebeck coefficient, and derivative of the Seebeck coefficient; E = f(T)

T E S dS/dT T E S dS/dT T E S dS/dT
K μV μV/K nV/K2 K μV μV/K nV/K2 K μV μV/K nV/K2
0 0.00 0.000 0.0 60 565.27 5.245 −69.6 120 790.55 2.682 −27.7
1 8.20 9.084 1645.5 61 570.48 5.176 −68.4 121 793.22 2.655 −27.4
2 18 .06 10.568 1329.6 62 575.62 5.108 −67.1 122 795.86 2.628 −27.0
3 29.24 11.757 1054.3 63 580.70 5.042 −66. 0 123 798.48 2.601 −26.7
4 41.48 12.689 815.3 64 585.70 4.976 −64.8 124 801.07 2.574 −26.4
5 54.55 13.399 608.9 65 590.65 4.912 −63.7 125 803.63 2.548 −26.0
6 68.22 13.916 431.5 66 595.53 4.849 −62.6 126 806.16 2.522 −25.7
7 82.32 14.270 280.0 67 600.35 4.787 −61.5 127 808.67 2.497 −25.3
8 96.71 14.484 151.5 68 605.10 4.726 −60.4 128 811.15 2.471 −24.9
9 111.25 14.580 43.4 69 609.80 4.666 −59.3 129 813.61 2.447 −24.5
10 125.84 14.577 −46.7 70 614.43 4.607 −58.2 130 816.05 2.422 −24.1
11 140.38 14.492 −121.0 71 619.01 4.550 −57.1 131 818.46 2.398 −23.7
12 154.80 14.340 −181.4 72 623.53 4.493 −56.0 132 820.85 2.375 −23.3
13 169.04 14.133 −229.7 73 628.00 4.438 −54.9 133 823.21 2.352 −22.9
14 183.05 13.884 −267.4 74 632.41 4.383 −53.o 134 825.55 2.329 −22.5
15 196.80 13.601 −296.0 75 636.77 4.330 −52.8 135 827.87 2.307 −22.1
16 210.25 13.294 −316.8 76 641.07 4.278 −51.7 136 830.16 2.285 −21.7
17 223.38 12.970 −331.0 77 645.32 4.226 −50.7 137 832.44 2.263 −21.3
18 236.18 12.634 −339.4 78 64Q.52 4.176 −49.6 138 834.69 2.242 −20.9
19 248.65 12.293 −343.1 79 653.67 4.127 −48.6 139 836.92 2.222 −20.5
20 260.77 11.950 −342.8 80 657.78 4.079 −47.6 140 839.13 2.201 −20.1
21 272.55 11.608 −339.2 81 661.83 4.032 −46.6 141 841.32 2.181 −19.7
22 283.99 11.272 −333.0 82 665.84 3.986 −45.6 142 843.50 2. 162 −19.3
23 295.09 10.943 −324.7 83 669.81 3.941 −44.6 143 845.65 2. 143 −19.0
24 305.88 10.623 −314.p 84 673.72 3.897 −43.7 144 847.78 2.124 −18.6
25 316.34 10.314 −303.7 85 677.60 3.853 −42.8 145 849.90 2. 105 −18.3
26 326.51 10.016 −291.7 86 681.43 3.811 −42.0 146 851.99 2.087 −18.0
27 336.38 9.731 −279.1 87 685.22 3.769 −41.1 147 854.07 2.069 −17.6
28 345.97 9.458 −266.3 88 688.97 3.729 −40.3 148 856.13 2.052 −17.3
29 355.30 9. 198 −253.3 89 692.68 3.689 −39.6 149 858.17 2.035 −17.1
30 364.37 8.951 −240.4 90 696.35 3.650 −38.9 150 860.20 2.018 −16.8
31 373.21 8.717 −227.8 91 699.98 3.611 −38.2 151 862.21 2.001 −16.5
32 381.81 8.495 −215.5 92 703.57 3.573 −37.5 152 864.20 1.985 −16.3
33 390.20 8.286 −203.7 93 707.13 3.536 −36.9 153 866.18 1.969 −16.1
34 398.39 8.088 −192.3 94 710.64 3.499 −36.3 154 868.14 1.953 −15.9
35 406.38 7.901 −181.6 95 714.12 3.463 −35.7 155 870.08 1.937 −15.7
36 414.19 7.725 −171.4 96 717.57 3.428 −35.2 156 872.01 1.921 −15.5
37 421.83 7.558 −161.8 97 720.98 3.393 −34.7 157 873.93 1.906 −15.4
38 429.31 7.401 −152.9 98 724.36 3.359 −34.3 158 875.82 1.890 −i5.3
39 436.64 7.252 −144.6 99 727.70 3.324 −33.8 159 877.71 1.875 −15.1
40 443.82 7.111 −136.9 100 731.01 3.291 −33.4 160 879.57 1.860 −15.0
41 450.86 6.978 −129.8 101 734.28 3.258 −33.0 161 881.43 1.845 −14.9
42 457.78 6.851 −123.3 102 737.52 3.225 −32.7 162 883.26 1.830 −14.9
43 464.57 6.731 −117.4 103 740.73 3. 192 −32.4 163 885.09 1.815 −14.8
44 471.24 6.616 −111.9 104 743.91 3. 160 −32.0 164 886.90 1.801 −14.7
45 477.80 6.507 −107.0 105 747.05 3.128 −31.7 165 888.69 1.786 −14.7
46 484.25 6.402 −102.5 106 750.16 3.097 −31.4 166 890.47 1.771 −14.6
47 490.61 6.302 −98.4 107 753.24 3.065 −31.2 167 892.23 1.757 −14.6
48 496.86 6.205 −94.8 108 756.29 3.034 −30.9 168 893.98 1.742 −14.5
49 503.02 6.112 −91.4 109 759.31 3.003 −30.6 169 895.71 1.728 −14.5
50 509.09 6.022 −88.4 110 762.30 2.973 −30.4 170 897.44 1.713 −14.5
51 515.06 5.935 −85.7 111 765.26 2.943 −30.1 171 899.14 1.699 −14.4
52 520.96 5.851 −83.2 112 768.19 2.913 −29.9 172 900.83 1. 684 −14.4
53 526.77 5.769 −81.0 113 771.08 2.883 −29.6 173 902.51 1.670 −14.4
54 532.49 5.689 −79.0 114 773.95 2.854 −29.4 174 904.17 1.655 −14.3
55 538.14 5.611 −77.1 115 776.79 2.824 −29.1 175 905.82 1.641 −14.3
56 543.72 5.534 −75.4 116 779.60 2.795 −28.8 176 907.45 1.627 −14.2
57 549.21 5.460 −73.8 117 782.38 2.767 −28.6 177 909.07 1.613 −14.2
58 554.64 5.387 −72.3 118 785.13 2.738 −28.3 178 910.68 1.599 −14.1
59 559.99 5.315 −70.9 119 787.86 2.710 −28.0 179 912.27 1.585 −14.0
60 565.27 5.245 −69.6 120 790.55 2.682 −27.7 180 913.85 1. 571 −13.9
180 913.85 1.571 −13.9 240 988.94 0.988 −7.7
181 915.41 1.557 −13.8 241 989.92 0.981 −7.5
182 916.96 1.543 −13.7 242 990.90 0.973 −7.2
183 918.50 1.529 −13.5 243 991.87 0.966 −6.9
184 920.02 1.516 −13.4 244 992.83 0.960 −6.6
185 921.53 1.503 −13.3 245 993.79 0.953 −6.3
186 923.03 1.489 −13.1 246 994.74 0.947 −5.9
187 924.51 1.476 −12.9 247 995.68 0.941 −5.6
188 925.98 1.464 −12.7 248 996.62 0.936 −5.3
189 927.44 1.451 −12.5 249 997.55 0.931 −5.0
190 928.88 1.439 −12.3 250 998.48 0.926 −4.7
191 930.31 1.426 −12.1 251 999.40 0.921 −4.5
192 931.73 1.414 −11.9 252 1000.32 0.917 −4.3
193 933.14 1.403 −11.6 253 1001.24 0.912 −4.2
194 934.54 1.391 −11.4 254 1002.15 0.908 −4.2
195 935.92 1.380 −11.2 255 1003.05 0. 904 −4.2
196 937.30 1.369 −10.9 256 1003.95 0.900 −4.3
197 938.66 1.358 −10.7 257 1004.85 0.895 −4.5
198 940.01 1.347 −10.4 258 1005.75 0.891 −4.8
1 99 941.36 1.337 −10.2 259 1006.63 0.886 −5.2
200 942.69 1.327 −9.9 260 1007.52 0.880 −5.7
201 944.01 1.317 −9.7 261 1008.39 0. 874 −6.3
202 945.32 1.308 −9.5 262 1009.27 0.868 −6.9
203 946.63 1.298 −9.3 263 1010. 13 0.860 −7.6
204 947.92 1.289 −9.1 264 1010.99 0.852 −8.3
205 949.20 1.280 −8.9 265 1011.83 0. 844 −9.0
206 950.48 1.271 −8.7 266 1012.67 0. 834 −9.7
207 951.75 1.263 −8.5 267 1013.50 0.824 −10.2
208 953.01 1.254 −8.4 268 1014.32 0.814 −10.5
209 9 54.26 1.246 −8.3 269 1015. 13 0.803 −10.6
210 955.50 1.238 −8.2 270 1015.93 0.793 −10.2
211 956.73 1.230 −8.1 271 1016.72 0.783 −9.3
212 957.96 1.222 −8.0 272 1017.50 0.775 −7.7
213 959. 17 1.214 −8.0 273 1018.27 0.768 −5.2
214 960.38 1.206 −7.9 274 1019.03 0.765 −1.6
215 961.59 1. 198 −7.9 275 1019.80 0.765 3.4
216 962.78 1. 190 −7.9 276 1020.57 0. 772 10.0
217 963.96 1.182 −7.9 277 1021.34 0.786 18.6
218 965. 14 1.174 −8.0 278 1022. 14 0.810 29.6
219 966.31 1.166 −8.0 279 1022.97 0.846 43.4
220 967.47 1.158 −8.1 280 1023.84 0. 898 60.5
221 968.63 1.150 −8.1
222 969.77 1.142 −8.2
223 970.91 1.133 −8.3
224 972.04 1.125 −8.4
225 973.16 1.116 −8.5
226 974.27 1.108 −8.6
227 975.38 1.099 −8.6
228 976.47 1.091 −8.7
229 977.56 1.082 −8.7
230 978.64 1.073 −8.8
231 979.70 1.064 −8.8
232 980.76 1.056 −8.8
233 981.82 1.047 −8.8
234 982.86 1.038 −8.7
235 983.89 1.029 −8.6
236 984.92 1.021 −8.5
237 985.93 1.013 −8.4
238 986.94 1.004 −8.2
239 987.94 0.996 −8.0
240 988.94 0.988 −7.7

Table 9.

Thermocouple “normal” silver versus Au-0.07 at% Fe11 – thermoelectric voltage, Seebeck coefficient, and derivative of the Seebeck coefficient; E = f(T)

T E S dS/dT T E S dS/dT T E S dS/dT
K μV μV/K nV/K2 K μV μV/K nV/K2 K μV μV/K nV/K2
0 0.00 0.000 0.0 60 700.37 8.447 −81.3 120 1099.00 5.267 −37.0
1 7.74 8.478 1402.0 61 708.77 8.367 −79.7 121 1104.25 5.230 −36.8
2 16.88 9.774 1193.0 62 717.10 8.288 −78.2 122 1109.46 5.194 −36.5
3 27.22 10.872 1006.5 63 725.35 8.210 −76.7 123 1114.63 5.157 −36.2
4 38.57 11.794 840.7 64 733.52 8.134 −75.3 124 1119.77 5.121 −36.0
5 50.76 12.560 693.6 65 741.62 8.060 −74.0 125 1124.88 5.085 −35.7
6 63.64 13.187 563.5 66 749.64 7.986 −72.7 126 1129.94 5.050 −35.5
7 77.09 13.692 448.8 67 757.59 7.914 −71.4 127 1134.98 5.014 −35.3
8 90.99 14.089 348.0 68 765.47 7.843 −70.2 128 1139.97 4.979 −35.0
9 105.24 14.392 259.7 69 773.28 7.774 −69.1 129 1144.93 4.944 −34.8
10 119.75 14.612 182.8 70 781.02 7.705 −67.9 130 1149.86 4.910 −34.5
11 134.44 14.761 116.0 71 788.69 7.638 −66.8 131 1154.75 4.875 −34.3
12 149.25 14.847 58.4 72 796.29 7.572 −65.8 132 1159.61 4.841 −34.0
13 164.11 14.880 8.9 73 803.83 7.506 −64.7 133 1164.44 4.807 −33.8
14 17 8.99 14.868 −33.3 74 811.31 7.442 −63.7 134 1169.23 4.774 −33.5
15 193.84 14.816 −68.9 75 818.72 7.379 −62.7 135 1173.98 4.740 −33.3
16 208.61 14.732 −98.8 76 826.06 7.317 −61.7 136 1178.71 4.707 −33.0
17 223.29 14.620 −123.6 77 833.35 7.255 −60.8 137 1183.40 4.674 −32.8
18 237.85 14.486 −143.9 78 840.57 7. 195 −59.8 138 1188.06 4.642 −32.5
19 252.26 14.333 −160.3 79 847.74 7. 136 −58.9 139 1192.68 4.609 −32.3
20 266.51 14.166 −173.1 80 854.85 7.077 −58.0 140 1197.28 4.577 −32.0
21 280.59 13.988 −183.0 81 861.90 7.020 −57.1 141 1201.84 4.545 −31.7
22 294.48 13.801 −190.2 82 868.89 6.963 −56.3 142 1206.37 4.514 −31.5
23 308.19 13.608 −195.2 83 875.82 6.907 −55.4 143 1210.86 4.482 −31.2
24 321.70 13.412 −198.2 84 882.70 6.852 −54.6 144 1215.33 4.451 −31.0
25 335.01 13.213 −199.5 85 889.53 6.798 −53.8 145 1219.77 4.420 −30.7
26 348.12 13.013 −199.5 86 896.30 6.745 −53.0 146 1224.17 4.390 −30.5
27 361.03 12.814 −198.3 87 903.02 6.692 −52.2 147 1228.55 4.359 −30.3
28 373.75 12.617 −196.1 88 909.68 6.640 −51.5 148 1232.89 4.329 −30.0
29 386.27 12.422 −193.2 89 916.30 6.589 −50.7 149 1237.20 4.299 −29.8
30 398.60 12.231 −189.6 90 922.86 6.539 −50.0 150 1241.49 4.270 −29.5
31 410.73 12.043 −185.5 91 929.37 6.489 −49.3 151 1245.74 4.240 −29.3
32 42 2.68 11.860 −181.0 92 935.84 6.440 −48.7 152 1249.97 4.211 −29.1
33 434.45 11.681 −176.3 93 942.25 6.392 −48.0 153 1254.17 4.182 −28.8
34 446.05 11.507 −171.4 94 948.62 6.344 −47.4 154 1258.33 4.153 −28.6
35 457.47 11.338 −166.4 95 954.94 6.297 −46.8 155 1262.47 4.125 −28.4
36 468.72 11.174 −161.3 96 961.22 6.250 −46.2 156 1266.58 4.097 −28.2
37 479.82 11.016 −1.56.3 97 967.44 6.205 −45.6 157 1270.67 4.068 −28.0
38 .490.76 10.862 −151.3 98 973.63 6.159 −45.1 158 1274.72 4.041 −27.8
39 501.54 10.713 −146.4 99 979.76 6.114 −44.6 159 1278.75 4.013 −27.6
40 512.19 10.569 −141.6 100 985.85 6.070 −44.1 160 1282.75 3.985 −27.4
41 522.68 10.430 −136.9 101 991.90 6.026 −43.6 161 1286.72 3.958 −27.2
42 533.05 10.295 −132.5 102 997.91 5.983 −43.1 162 1290.66 3.931 −27.0
43 543.28 10.165 −128.2 103 1003.87 5.940 −42.6 163 1294.58 3.904 −26.8
44 553.38 10.039 −124.1 104 1009.79 5.898 −42.2 164 1298.47 3.877 −26.6
45 563.36 9.917 −120.1 105 1015.66 5.856 −41.8 165 1302.34 3.851 −26.4
46 573.21 9.798 −116.4 106 1021.50 5.814 −41.4 166 1306.17 3.825 −26.3
47 582.95 9.684 −112.9 107 1027.29 5.773 −41.0 167 1309.98 3.798 −26.1
48 592.58 9.573 −109.5 108 1033.04 5.732 −40.6 168 1313.77 3.772 −25.9
49 602.10 9.465 −106.3 109 .1038.76 5.692 −40.3 169 1317.53 3.747 −25.8
50 611.51 9.360 −103.3 110 1044.43 5.651 −39.9 170 1321.26 3.721 −25.6
51 620.82 9.258 −100.5 111 1050.06 5.612 −39.6 171 1324.97 3.695 −25.5
52 630.03 9.159 −97.9 112 1055.65 5.572 −39.3 172 1328.65 3.670 −25.3
53 639.14 9.062 −95.3 113 1061.20 5.533 −39.0 173 1332.31 3.645 −25.1
54 648.15 8.968 −93.0 114 1066.72 5.494 −38.7 174 1335.94 3.620 −25.0
55 65 7.08 8.876 −90.7 115 1072.19 5.456 −38.4 175 1339.55 3.595 −24.8
56 665.91 8.787 −88.6 116 1077.63 5.418 −38.1 176 1343.13 3.570 −24.7
57 674.65 8.699 −86.7 117 1083.03 5.380 −37.8 177 1346.69 3.545 24.5
58 683.31 8.613 84.8 118 1088.39 5.342 −37.5 178 1350.22 3.521 24.4
59 691.88 8.529 −83.0 119 1093.71 5.304 −37.3 179 1353.73 3.497 24.2
60 700.37 8.447 −81.3 120 1099.00 5.267 −37.0 180 1357.22 3.472 −24.1
180 1357.22 3.472 −24.1 240 1528.08 2.288 −18.2
181 1360.68 3.448 −23.9 241 1530.36 2.270 −18.1
182 1364. 11 3.425 −23.8 242 1532.62 2.252 −18.0
183 1367.53 3.401 —2 3.6 243 1534.86 2.234 −17.9
184 1370.92 3.377 −23.4 244 1537.09 2.216 −17.7
185 1374.28 3.354 −23.3 245 1539.29 2.198 −17.6
186 1377.62 3.331 −23.1 246 1541.48 2.181 −17.3
187 1380.94 3.308 −22.9 247 1543.65 2.163 −17.1
188 1384.24 3.285 −22.8 248 1545.81 2.146 −16.8
189 1387.51 3.262 −22.6 249 1547.95 2.130 −16.5
190 13 90.76 3.240 −22.4 250 1550.07 2.113 −16.1
191 1393.99 3.217 −22.2 251 1552.17 2.098 −15.7
192 1397.20 3.195 −22.0 252 1554.26 2.082 −15.3
193 1400.38 3.173 −21.9 253 1556.34 2.067 −14.8
194 1403.54 3.152 −21.7 254 1558.40 2.053 −14.3
195 1406.69 3. 130 −21.5 255 1560.44 2.038 −13.8
196 1409.80 3.109 −21.3 256 1562.48 2.025 −13.2
197 1412.90 3.087 −21.1 257 1564.49 7.012 −12.6
198 1415.98 3.067 −20.9 258 1566.50 2.000 −12.1
199 1419.04 3.046 −20.7 259 1568.49 1.988 −11.5
200 1422.07 3.025 −20.5 260 1570.48 1.977 −10.9
201 1425.09 3.005 −20.3 261 1572.45 1.066 −10.4
202 1428.08 2.985 −20.1 262 1574.41 1.956 −9.9
203 1431.06 2.965 −19.9 263 1576.36 1.946 −9.4
204 1434.01 2.945 −19.7 264 1578.30 1 .937 −9.1
205 1436.94 2.925 −19.6 265 1580.23 1.928 −8.8
206 1439.86 2.906 −19.4 266 1582.16 1.920 −8.6
207 1442.76 2.886 −19.2 267 1584.07 1.911 −8.6
208 1445.63 2.867 −19.0 268 1585.98 1.902 −8.7
209 1448.49 2.848 −18.9 269 1587.88 1.893 −9.1
210 1451.33 2.829 −18.7 270 1589.77 1 .884 −9.7
211 1454.15 2.811 −18.6 271 1591.65 1.874 −10.5
212 1456.95 2.792 −18.5 272 1593.51 1.863 −11.7
213 1459.73 2.774 −18.3 273 1595.37 1.851 −13.2
214 1462.50 2.755 −18.2 274 1597.21 1.836 −15.1
215 1465.24 2.737 −18.1 275 1599.04 1.820 −17.4
216 1467.97 2.719 −18.0 276 1600.85 1.801 −20.2
217 1470.68 2.701 −18.0 277 1602.64 1.780 −23.6
218 1473.38 2.683 −17.9 278 1604.41 1.754 −27.6
219 1476.05 2.665 −17.9 279 1606.15 1.724 −32.3
220 1478.71 2.648 −17.8 280 1607.86 1.689 −37.7
221 1481.34 2.630 −17.8
222 1483.97 2.612 −17.8
223 1486.57 2.594 −17.8
224 1489.15 2.576 −17.8
225 1491.72 2.559 −17.8
226 1494.27 2.541 −17.8
227 1496.80 2.523 −17.8
228 1499.32 2.505 −17.9
229 1501.81 2.487 −17.9
230 1504.29 2.469 −18.0
231 1506.75 2.451 −18.0
232 1509. 19 2.433 −18.1
233 1511.62 2.415 −18.1
234 1514.03 2.397 −18.2
235 1516.41 2.379 −18.2
236 1518.78 2.361 −18.2
237 1521.13 2.342 −18.2
238 1523.47 2.324 −18.7
239 1525.78 2.306 −18.2
240 1528.08 2.288 −18.2

Table 10.

Thermocouple “normal” silver versus Au-0.02 at% Fe45 – thermoelectric voltage, Seebeck coefficient, and derivative of the Seebeck coefficient; E = f(T)

T E S dS/dT T E S dS/dT T E S dS/dT
K μV μV/K nV/K2 K μV μV/K nV/K2 K μV μV/K nV/K2
0 0.00 0.000 0.0 60 546.11 4.361 −69.2 120 727.52 2.115 −22.9
1 8.17 9.032 1624.0 61 550.44 4.293 −67.2 121 729.62 2.092 −22.7
2 17.96 10.503 1325.6 62 554.70 4.227 −65.2 122 731.70 2.069 −22.5
3 29.08 11.695 1063.4 63 558.89 4. 163 −63.3 123 733.76 2.047 −22.3
4 41.27 12.641 833.7 64 563.02 4. 100 −61.6 124 735.80 2.025 −22.0
5 54.29 13.372 633.5 65 567.09 4.039 −59.9 125 737.81 2.003 −21.8
6 67.95 13.917 459.6 66 571.10 3.980 −58.4 126 739.80 1.981 −21.6
7 82.07 14.299 309.5 67 575.05 3.923 −56.9 127 741.77 1.960 −21.3
8 96.50 14.543 180.6 68 578.95 3.867 −55.4 128 743.72 1.939 −21.1
9 111.11 14.667 70.7 69 5 8 2.79 3.812 −54.0 129 745.65 1.918 −20.8
10 125.80 14.690 −22.4 70 586.57 3.758 −52.7 130 747.56 1.897 −20.6
11 140.46 14.627 −100.5 71 590.30 3.706 −51.4 131 749.44 1.876 −20.3
12 155.03 14.493 −165.3 72 593.98 3.656 −50.1 132 751.31 1.856 −20.1
13 169.43 14.300 −218.4 73 597.61 3.606 −48.9 133 753.16 1.836 −19.8
14 183.61 14.060 −261.2 74 601.20 3.558 −47.8 134 754.98 1.817 −19.5
15 197.54 13.781 −294.9 75 604.73 3.511 −46.6 135 756.79 1.797 −19.3
16 211.17 13.473 −320.8 76 608.22 3.465 −45.5 136 758.58 1.778 −19.0
17 224.48 13.142 −339.9 77 611.66 3.420 −44.4 137 760.35 1.759 −18.7
18 237.45 12.795 −353.1 78 615.06 3.376 −43.4 138 762.10 1.741 −18.5
19 250.06 12.437 −361.2 79 618.41 3.333 −42.4 139 763.83 1.722 −18.2
20 262.32 12.074 −365.1 80 621.72 3.291 −41.4 140 765.54 1.704 −17.9
21 274.21 11.708 −365.3 81 624.99 3.250 −40.4 141 767.24 1.686 −17.7
22 285.73 11.344 −362.5 82 628.22 3.210 −30.5 142 768.91 1.669 −17.4
23 296.90 10.984 −357.1 83 631.41 3.171 −38.6 143 770.57 1.652 −17.2
24 307.70 10.630 −349.8 84 634.57 3. 133 −37.7 144 772.22 1.635 −16.9
25 318.16 10.285 −340.8 85 637.68 3.095 −36.9 145 773.84 1.618 −16.7
26 328.28 9.949 −330.5 86 640.76 3.059 −36.1 146 775.45 1.601 −16.4
27 338.06 9.624 −319.3 87 643.80 3.023 −35.3 147 777.05 1.585 −16.2
28 347.53 9.311 −307.4 88 646.80 2. 988 −34.6 148 778.62 1.569 −16.0
29 356.69 9.010 −295.0 89 649.77 2.954 −33.9 149 780.18 1.553 −15.8
30 365.55 8.721 −282.4 90 652.71 2.921 −33.2 150 781.73 1.537 −15.6
31 374.14 8.445 −269.7 91 655.62 2.888 −32.5 151 783.26 1.522 −15.4
32 382.45 8.182 −257.0 92 658.49 2.856 −31.9 152 784.77 1.507 −15.2
33 390.50 7.931 −244.6 93 661.33 2. 824 −31.3 153 786.27 1.491 −15.0
34 398.31 7.692 −232.4 94 664.14 2.793 −30.7 154 787.75 1.476 −14.9
35 405.89 7.466 −220.5 95 666.91 2.762 −30.2 155 789.22 1.462 −14.7
36 413.25 7.251 −209.1 96 669.66 2.733 −29.7 156 790.68 1.44 7 −14.6
37 420.40 7.048 −198.1 97 672.38 2.703 −29.2 157 792.12 1.433 −14.4
38 427.35 6.855 −187.6 98 675.07 2.674 −28.8 158 793.54 1.418 −14.3
39 434.11 6.672 −177.6 99 677.73 2.646 −28.3 159 794.95 1.404 −14.2
40 440.70 6.499 −168.2 100 680.36 2.617 −27.9 160 796.35 1.390 −14.1
41 447.11 6.336 −159.2 101 682 .96 2.590 −27.6 161 797.73 1.376 −14.0
42 453.37 6.181 −150.8 102 685 .54 2.562 −27.2 162 799.10 1.362 −13.9
43 459.48 6.034 −143.0 103 688.09 2.535 −26.9 163 800.46 1.348 −13.8
44 465.44 5.895 −135.6 104 690.61 2.508 −26.6 164 801.80 1.334 −13.8
45 471.27 5.763 −128.7 105 693.10 2.482 −26.3 165 803.13 1.320 −13.7
46 476.97 5.637 −122.3 106 695.57 2.456 −26.0 166 804.44 1.307 −13.7
47 482.55 5.518 −116.4 107 698.02 2.430 −25.7 167 805.74 1.293 −13.6
48 488.01 5.404 −110.9 108 700.43 2.404 −25.5 168 807.03 1.279 −13.6
49 493.36 5.296 −105.7 109 702.82 2.379 −25.2 169 808.30 1.266 −13.5
50 498.60 5.193 −101.0 110 705.19 2.354 −25.0 170 809.56 1.252 −13.5
51 503.74 5.094 −96.6 111 707.53 2.329 −24.8 171 810.80 1.239 −1 3.4
52 508.79 4.999 −92.6 112 709.85 2.305 −24.5 172 812.04 1.226 −13.4
53 513.74 4.909 −88.8 113 712.14 2.280 −24.3 173 813.25 1.212 −13.4
54 518.61 4.822 −85.4 114 714.41 2.256 −24. 1 174 814.46 1.199 −13.3
55 523.39 4.738 −82.2 115 716.65 2.232 −23.9 175 815.65 1.186 −13.3
56 528.09 4.657 −79.2 116 718.87 2.208 −23.7 176 816.83 1.172 −13.2
57 532.70 4.579 −76.4 117 721.07 2.184 −23.5 177 818.00 1.159 −13.2
58 537.25 4.504 −73.9 118 723.24 2.161 −23.3 178 819.15 1. 146 −13.2
59 541.71 4.432 −71.5 119 725.39 2.138 −23.1 179 820.29 1.133 −13.1
60 546.11 4.361 −69.2 120 727.52 2.115 −22.9 180 821.41 1.120 −13.0
 180 821.41 1.120 −13.0 240 869.29 0.524 −8.6
 181 822.53 1 .1 07 −13.0 241 869.81 0.516 −8.5
 182 823.63 1 .094 −12.9 242 870.32 0.507 −8.4
 183 824.71 1 .081 −12.8 243 870.82 0.499 −8.2
 184 825.79 1 .068 −12.7 244 871.32 0.491 −8.0
 185 826.85 1 .055 −12.6 245 871.80 0.483 −7.0
186 827.90 1 .043 −12.5 246 872.28 0.475 −7.7
 187 828.94 1 .0 30 −12.4 247 872.75 0.468 −7.5
 188 829.96 1 .018 −12.3 248 873.22 0.460 −7.3
 189 830.97 1 .006 −12.2 249 873.68 0.453 −7.1
 190 831.97 0 .994 −12.1 250 874.12 0.4 46 −6.8
 191 832.96 0.982 −11 .9 251 874.57 0.4 39 −6.6
 192 833.94 0.970 −11.8 252 875.00 0.433 −6.5
 193 834.90 0 .958 −11.6 253 875.43 0.426 −6.3
 194 835.85 0.946 −11.5 254 875.86 0.420 −6.1
 195 836.79 0.935 −11.3 255 876.27 0.414 −6.0
 196 837.72 0 .024 −11.1 256 876.68 0.408 −5.0
 197 838.64 0.913 −11.0 257 877.09 0.40 2 −5.9
 198 839.55 0 .902 −10.8 258 877.49 0.396 −5.8
 199 840.44 0.891 −10.6 259 877.88 0.391 −5.0
 200 841.33 0.881 −10.4 260 878.27 0.385 −6.0
 201 842.20 0 .870 −10.3 261 878.65 0. 379 −6.1
 202 843.07 0.860 −10.1 262 879.03  0.372 −6.3
 203 843.93 0 .850 −9.9 263 879.40 0. 366 −6.5
 204 844.77 0 .840 −9.8 264 879.76 0.3 59 −6.8
 205 845.61 0.831 −9.6 265 880.12 0.353 −7.1
 206 846.43 0.821 −9.5 266 880.46 0.345 −7.4
 207 847.25 0.812 −9.3 267 880.81 0.338 −7.7
 208 848.05 0.802 −9.2 268 881.14 0.330 −7.9
 209 848.85 0.793 −9.1 269 881.47 0.322 −8.1
 210 849.64 0.784 −8.9 270 881.78 0.314 −8.2
 211 850.42 0 .775 −8.8 271 882.09 0.305 −8.2
 212 851.1 9 0.767 −8.7 272 882.39 0.297 −7.9
 213 851.95 0.758 −8.7 273 882.69 0.290 −7.3
 214 852.71 0 .749 −8.6 274 882.97 0.283 −6.3
 215 853.45 0.741 −8.5 275 883.25 0.277 −4.8
 216 854.19 0.732 −8.5 276 883.53 0. 274 −2.7
 217 854.92 0 .724 −8.5 277 883.80 0.272 0.2
 218 855.64 0.715 −8.4 278 884.08 0. 7 74 4.0
 219 856.35 0 .70 7 −8.4 279 884.35 0.281 9.0
 220 857.05 0 .698 −8.4 280 884.64 0.293 15.3
 221 857.74 0 .690 −8.5
 222 858.43 0.681 −8.5
 223 859.11 0.673 −8.5
 224 859.78 0.664 −8.5
 225 860.4 4 0.656 −8.6
 226 861.09 0 .647 −8.6
 227 861.73 0.639 −8.7
 2 2 8 862.36 0.630 −8.7
 229 862.99 0.621 −8.8
 230 863.61 0.612 −8.8
 231 864.22 0.604 −8.8
 232 864.81 0.595 −8.9
 233 865.40 0 .586 −8.9
 234 865.99 0.577 −8.9
 235 866.56 0 .568 −8.9
 236 867.12 0.559 −8.9
 237 867.68 0.550 −8.8
 238 868.22 0.542 −8.8
 239 868.76 0.533 −8.7
 240 869.29 0 .524 −8.6

Acknowledgments

Mr. W. J. Hall was largely responsible for the computer programs used to fit the experimental data. Mr. Ed Zysk of Engelhard Industries and the late Dr. Bert Brenner of Sigmund Cohn Corporation were extremely cooperative in producing and supplying the Au-Fe test wire.

This work was carried out at the National Bureau of Standards under the sponsorship of the National Aeronautics and Space Administration, Space Nuclear Propulsion Office (SNPO–C), Contract R–45.

Footnotes

1

Figures in brackets indicate the literature references at the end of this paper.

2

KP is the ASTM and ISA designation for a 90% Ni + 10% Cr alloy. Trade names for this material are: Chromel, Hoskins Manufacturing Co.; Tophel, Wilbur B. Driver Co.; T–1, Driver-Harris Co.; and Thermo Kanthal KP, Kanthal Corp. Use of trade names does not constitute an endorsement of any manufacturer’s products.

3

Many experimental points have been omitted from the NBS curves throughout this paper in order to reduce the cluttered appearance of the point graphs. All experimental data were, however, used to determine the proper analytical representation and tables to be given later.

6. References

  • [1].Powell R. L., Caywood L. P., and Bunch M. D., Low-Temperature Thermocouples, Chapter in Temperature, Its Measurement and Control in Science and Industry 3, Part 2, 65–77 (Reinhold Publishing Corp., New York, N.Y., 1962). [Google Scholar]
  • [2].Borelius G., Keesom W. H., Johansson C. H., and Linde J. O., Measurement of the thermoelectric force per degree of some alloys down to the temperature of liquid hydrogen, and calculation of the Thomson-effect. Proc. Kon. Akad. Amsterdam 33, 17, 23–36 (1930). [Google Scholar]
  • [3].Borelius G., Keesom W. H., Johansson C. H., and Linde J. O., Measurements on thermoelectric forces down to temperatures obtainable with liquid or solid hydrogen, Proc. Kon. Akad. Amsterdam 35, 15, 22–33 (1932). [Google Scholar]
  • [4].Berman R., and Huntley D. J., Dilute gold-iron alloys as thermocouple material for low temperature heat conductivity measurements, Cryogenics 3, 70–76 (June 1963). [Google Scholar]
  • [5].Finnemore D. K., Ostenson J. E., and Stromberg T. F., Secondary thermometer for the 4 to 20 K range, Rev. Sci. Iustrum. 36, No. 9, 1369–1370 (September 1965). [Google Scholar]
  • [6].Berman R., Brock J. C. F., and Huntley D. J., Properties of gold + 0.03 percent (at.) iron thermoelements between 1 and 300 K and behavior in a magnetic field, Cryogenics 4, 223–239 (August 1964). [Google Scholar]
  • [7].Rosenbaum R. L., Some properties of gold-iron thermocouple wire, Rev. Sci. Instrum. 39, No. 6, 890–899 (1968). [Google Scholar]
  • [8].Rosenbaum R. L., Some low temperature thermometry observations, Rev. Sci. Iustrum. 40, No. 4, 577–583 (April 1969). [Google Scholar]
  • [9].Sparks L. L., Powell R. L., and Hall W. J., Reference Tables for Low Temperature Thermocouples, Nat. Bur Stand. (U.S.), Monogr. 124, to be published. [Google Scholar]
  • [10].Björck A., Solving linear least squares problems by Gram-Schmidt orthogonalization, Bit, Nordisk Tidsprift for Informationsbehandling, 7, 1–21 (1967). [Google Scholar]
  • [11].Powell R. L., Hall W. J., and Hust J. G., The fitting of resistance thermometer data by orthogonal functions, Fifth Symposium on Temperature, Washington, D.C., June 21–24, 1971. [Google Scholar]
  • [12].Reference Base of the Volt to be Changed, Nat. Bur. Stand. (U.S.), Tech. News Bull. 52, 204–206 (September 1968). [Google Scholar]
  • [13].International Practical Temperature Scale of 1968, Adopted by the Comité International des Poids et Mesures, Metrologia 5, No. 2, 35–44 (April 1969). [Google Scholar]
  • [14].Bedford R. F., Durieuz M., Muijlwijk R., and Barber C. R., Relationships between the International Practical Temperature Scale of 1968 and the NBS–55, NPL–61, PRMI–54, and PSU–54 temperature scales in the range from 13.81 to 90.188 K. Metrologia 5, No. 2, 47–49 (April 1969). [Google Scholar]
  • [15].Bedford R. E., Kirby C. G. M., Notes on the application of the International Practical Temperature Scale of 1968, Metrologia 5, No. 3, 83–87 (July 1969). [Google Scholar]
  • [16].Rogers J. S., Tainish R. J., Anderson M. S., and Swenson C. A., Comparison between gas thermometer, acoustic, and platinum resistance temperature scales between 2 and 20 K, Metrologia 4, No. 2, 47–58 (April 1969). [Google Scholar]
  • [17].Plumb H. H., and Cataland G., Acoustical thermometer and the National Bureau of Standards Provisional Temperature Scale 2–20 (1965), Metrologia, 2, No. 4, 127–139 (1966). [Google Scholar]
  • [18].Anderson H. H., and Nielsen M., Thermo-electricity in gold at low temperatures, Physics Lett. 6, No. 1, 17–18 (August 15, 1963). [Google Scholar]

Articles from Journal of Research of the National Bureau of Standards. Section A, Physics and Chemistry are provided here courtesy of National Institute of Standards and Technology

RESOURCES