Table 3.

Descriptive statistics for the variable Temperature (with and without cooling) with all combinations of parameters (in °C)

Parameter	N	Cooling		No cooling
		MV ± SD	p = 0.05	MV ± SD	p = 0.05
Drill geometry
Standard	180/180	37.5 ± 1.2	39.8	45.5 ± 3.7	52.9
Two-step	180/180	37.5 ± 0.9	39.1	45.5 ± 3.6	52.5
Drill diameter (mm)
3.4	90/90	37.0 ± 0.8	38.5	43.4 ± 1.5	46.2
4.5	90/90	38.1 ± 1.2	40.5	47.7 ± 4.1	55.7
2.5/3.4	90/90	37.3 ± 1.0	39.3	43.8 ± 2.4	48.5
3.4/4.5	90/90	37.7 ± 0.6	38.9	47.3 ± 3.6	54.4
Feed (mm/rev)
0.02	40/40	37.4 ± 0.8	39.0	50.1 ± 5.9	61.6
0.04	80/80	37.5 ± 0.9	39.3	47.0 ± 2.8	52.4
0.10	120/120	37.4 ± 1.0	39.4	45.3 ± 2.3	49.8
0.16	80/80	37.5 ± 1.1	39.8	43.1 ± 1.7	46.4
0.18	40/40	37.7 ± 1.2	40.0	43.7 ± 2.9	49.3
Cutting speed (m/min)
1.18	40/40	37.0 ± 0.6	38.1	46.0 ± 1.9	49.6
10.68	80/80	37.4 ± 0.8	39.0	45.0 ± 3.2	51.2
33.61	120/120	37.6 ± 1.0	39.6	46.2 ± 4.9	55.7
56.55	80/80	37.6 ± 1.2	40.0	45.1 ± 2.9	50.7
66.05	40/40	37.7 ± 1.1	40.0	45.0 ± 2.5	49.9

N number of measurements (cooling/no cooling), MV mean value, SD standard deviation