Efficient Fabrication of Quartz Glass Using Laser Coaxial Powder-Fed Additive Manufacturing Approach

Abstract

This article investigates a laser-directed energy deposition additive manufacturing (AM) method, based on coaxial powder feeding, for preparing quartz glass. Through synergistic optimization of line deposition and plane deposition experiments, key parameters of laser coaxial powder feeding AM were identified. The corresponding mechanical properties, thermal properties, and microstructure of the bulk parts were analyzed. The maximum mechanical strength of the obtained quartz glass element reached 72.36 ± 5.98 MPa, which is ca. 95% that of quartz glass prepared by traditional methods. The thermal properties of the obtained quartz glass element were also close to those prepared by traditional methods. The present research indicates that one can use laser AM technology that is based on coaxial powder feeding to form quartz glass with high density and good thermodynamic properties. Such quartz glass has substantial potential in, for example, optics and biomedicine.

Highlights

• 1.A novel process of quartz glass using laser coaxial powder-fed additive manufacturing was developed.
• 2.The effect of process parameters on the properties of glass parts were studied.
• 3.Quartz glass specimen with high density and good mechanical strength was done.

Introduction

Glass—including quartz glass—is an important material in scientific and engineering applications. It has excellent mechanical, optical, and thermal properties. These properties have led to wide use in various fields (such as optics, biomedicine, and aerospace).^1–9 Traditional glass-manufacturing techniques require high-temperature melting, mold inversion, cooling forming, and other steps to impart a specific shape to glass. Such techniques are complex, costly, inefficient, and difficult in the context of preparing glass components with complex structures. Compared with traditional methods, additive manufacturing (AM) technology has the characteristics of simplicity, low cost, one-step formation of high-density parts, wide range of available materials, and no structural restrictions.^10–12

At present, AM has enabled rapid, flexible, high-quality preparation of components that consist of, for example, metals,^13,14 ceramics,^15,16 and polymers.^17,18 As indicated by the well-established applications of AM technology to the aforementioned materials, development of glass materials by laser AM technology has been an active area of research globally.

In recent years, relevant research on AM or laser-melting of glass has been reported. Fateri et al¹⁹ studied selective laser melting (SLM) of soda-lime glass. The effects of the particle size distribution and density of various powders on SLM of glass were analyzed. They pointed out that the particle size distribution had an effect on the sintering and characteristics of the final product. Therefore, powder with a narrow particle distribution is preferable, whether by conventional or AM methods of glass fabrication. Luo et al^20–22 used SLM to deposit a glass structure, and discussed the effects of the process parameters on stationary particle formation as well as continuous line quality. The absorption rate of glass powder was almost constant regardless of the process parameters.

Furthermore, AM has substantial potential for creating glass parts with complex geometries and structures. For instance, complex multilayer glass structures (such as a trabecular bone scaffold,⁵ a three-dimensional micromanipulator,⁷ a flow reactor channel,¹⁰ and vascularized engineered tissue²³) are easily formed by AM. The parts formed by SLM are often opaque; a stereolithography apparatus is a good alternative for printing glass with high transparency.^24–28 Liu et al^24,25 fabricated three-dimensional, luminous, transparent glass parts; manufactured with a stereolithography apparatus in combination with solution impregnation and high-temperature sintering. A multicolor glass that emitted distinguishable luminescence from various parts of the glass object was obtained by spatially selective doping. This work has substantial potential applications in integrated optics. Furthermore, Baudet et al²⁹ applied the characteristics of a low glass transition temperature (188°C) and easy processing of sulfide chalcogenide glass to fused deposition modeling of chalcogenide glass at 328°C.

However, the fragile characteristics of this glass product imparted difficulties to carrying out posttreatment technology other than annealing. Several references have reported use of wire-fed processes of directed energy deposition to form transparent glasses. Such glasses include soda-lime²² and quartz.^21,30,31

Although laser AM has been investigated extensively for use with various glass materials, fabrication of quartz glass objects by laser coaxial powder-fed (LCPF) AM technology is not well-developed; even though such technology is advantageous in terms of the deposition rate,³² density,^33,34 and mechanical properties³⁵ of the products. Grabe et al³¹ deposited a straight single weld by using wire-based laser glass deposition, and developed a numerical simulation model to describe the temperature distribution as well as the evaporation of glass in a glass fiber during the coaxial laser glass deposition. Because the process is in the initial stage of development, the optical and mechanical properties have not been characterized and analyzed yet.

In the present study, experimental investigations on AM of quartz glass by the LCPF process were conducted. Multiple quartz glass objects were fabricated and analyzed to investigate the influence of the process parameters. Key parameters that pertain to the quartz glass-forming size, density, and mechanical strength of the fabricated parts were identified and optimized.

Experimental Procedures

Commercially available SiO₂ powder with high purity (99.9%) was used; particle size distribution in the range of 65–120 μm. Morphological evaluations of the powder were performed by scanning electron microscopy (SEM). The powder was spherical with fine satellite particles attached (Fig. 1).

FIG. 1.

SEM micrograph of SiO₂ powder. SEM, scanning electron microscopy.

The LCPF machine consisted of a 220-W CO₂ laser, an annular nozzle (coaxial powder feeding system); a computerized, numerically controlled XYZ workbench; and a computer-aided system. Figure 2a shows a schematic of the LCPF AM used in the present study. The nozzle was fixed on the workbench. Figure 2b shows an enlarged view of the annular nozzle. Commercially available quartz glass (dimensions: 50 mm × 30 mm × 5 mm) was used as the substrate; the diameter of the beam spot at the substrate surface was 1.5 mm. The laser beam was coaxial with the powder through the nozzle, and the powder was melted and deposited onto the glass substrate. The relative configuration of the workbench and nozzle were adjusted until a neat-net product was formed by a layer-by-layer method.

FIG. 2.

LCPF process (a) schematic diagram and (b) photograph of the nozzle. LCPF, laser coaxial powder-fed.

During the entire experiment, nitrogen was the carrier and shielding gas. The coaxial and annular nitrogen gas flow rates were 3 and 6 L/min, respectively. In addition, the substrate was maintained at 430°C, which was helpful for decreasing the thermal gradient during the LCPF process and thus reducing sample cracking.

The present study investigated the influence of the main process parameters—such as laser power and scanning speed—on the AM quality (forming size, density, and thermodynamic properties) of fabricated quartz glass. The LCPF process is complex and consists of numerous parameters—such as the laser power, scanning speed, laser spot diameter, powder beam focus position, powder feed rate, descend height (layer thickness), and hatch space; all of which can affect the glass formation and final quality. The present strategy investigated the formation mechanism, by gradually progressing from line to plane to bulk deposition, because line deposition is the basis of the subsequent plane and bulk deposition. The s-scanning strategy, in which the next deposition track starts from the end of the previous deposition line, was used for the deposition of all the layers in the plane and bulk structures (except for line structures).

A formidable challenge is how to minimize the time that is required to identify optimal processing parameters for specific applications. First, the key parameters that affect the forming size of the line deposition experiments were determined by orthogonal experiments. Line depositions were carried out with the following parameters: laser power, laser scanning speed, powder beam focus position, and powder feeding rate. Except for four levels of laser power, five levels were considered for each parameter. Table 1 shows all of the processing parameters that were applied to 32 experiments of line deposition. Second, the effects of the descend height of the workbench and laser hatch space on the density were considered in the plane deposition experiments.

Table 1.

Parametric Analysis of Line Deposition

No.	Processing parameters				Geometry measurement
	P (W)	v (mm/s)	F (g/min)	O (mm)	H (mm)	W (mm)	N
1	99	0.6	1.4	−1.0	0.73	1.88	0.38
2	110	0.6	1.86	−0.5	0.78	1.9	0.41
3	121	0.6	2.3	0	1.18	2.56	0.46
4	132	0.6	2.8	0.5	1.53	2.62	0.58
5	121	0.7	1.86	−1.0	0.8	2.11	0.37
6	132	0.7	1.4	−0.5	0.52	2.03	0.25
7	99	0.7	2.8	0	1.29	2.68	0.48
8	110	0.7	2.3	0.5	0.89	2.19	0.40
9	132	0.8	2.3	−1.0	1.24	2.35	0.52
10	121	0.8	2.8	−0.5	1.13	2.38	0.47
11	110	0.8	1.4	0	0.93	1.83	0.50
12	99	0.8	1.86	0.5	0.55	1.63	0.33
13	110	0.9	2.8	−1.0	1.04	2.18	0.47
14	99	0.9	2.3	−0.5	1.57	2.19	0.71
15	132	0.9	1.86	0	0.75	2.16	0.34
16	121	0.9	1.4	0.5	0.89	2.35	0.37
17	99	1.0	3.25	1.0	0.84	1.63	0.51
18	110	1.0	3.25	−1.0	1.13	1.59	0.71
19	121	1.0	3.25	−0.5	0.83	1.93	0.43
20	132	1.0	3.25	0	1.39	2.42	0.57
21	110	0.6	1.4	1.0	1.17	2.53	0.46
22	121	0.7	1.86	1.0	0.8	2.25	0.35
23	132	0.8	2.3	1.0	0.59	1.77	0.33
24	∼99	0.9	2.8	1.0	0.89	2.16	0.41
25	∼99	1.0	1.4	0.5	1.05	1.94	0.54
26	∼121	0.6	3.25	0.5	1.57	2.19	0.71
27	∼99	0.7	3.25	∼−1.0	1.54	2.09	0.73
28	∼110	0.8	3.25	∼−1.0	1.27	2.41	0.52
29	∼132	0.9	3.25	∼−1.0	1.15	2.08	0.55
30	∼121	1.0	1.86	∼−1.0	0.72	1.69	0.42
31	∼110	1.0	2.3	∼−0.5	1.01	1.14	0.88
32	∼110	1.0	2.8	∼0	1.12	2.47	0.45

In the table, P is laser power, v is scanning speed, F is powder feeding rate, O is powder beam focus position, ∼ represents irrelevant data and can be arbitrarily valued.

Finally, the results of the bulk deposition experiments were summarized by using the laser energy density parameter defined with Equation (1).

$$E=\frac{P}{v\times h_d\times h}$$ (1)

where P is laser power, v is scanning speed, h_d is descend height of the x-y-z workbench, and h is hatch space. The parameters used for bulk deposition process are listed in Table 2.

Table 2.

Parameter Setting of Bulk Deposition Process

Parameter	Value
Laser energy density	171.88–286.46 J/mm3
Scanning speed	0.6–1.0 mm/s
Laser power	110 W
Laser spot diameter	1.5 mm
Powder feed rate	1.4 g/min
Descend height	0.8 mm
Scanning space	1.0 mm
Nozzle-to-work distance	10.4 mm

After the experiments, the samples that were manufactured by the LCPF process were cut with an auto-inner circle cutting machine into various dimensions as per the requirements; and were used to conduct various characterizations—including the forming size, density, microstructure, and mechanical performance. An optical microscope was used to investigate the geometrical features of the line deposition experiments. The densities of the printed bulk glasses were calculated by the Archimedes method with a precision analytical microbalance (accuracy: 0.1 mg).

Three-point bending tests at room temperature were carried out with a mechanical property testing machine (AC-50KIC; SHIMADZU) at an external load rate of 0.5 mm/min. The thermal diffusivity of the printed glasses was determined by the laser flash method with a Netzsch LFA 457 laser thermal conductivity apparatus. The specific heat capacity of the powder samples was measured by differential scanning calorimetry (LFA 427 MicroFlash; Netzsch). The microstructures and pores of the samples were investigated by SEM (PhenomXL; Phenom World) and with an ultrasonic scanning microscope (Sonix ECHO-LS; Sonix).

Results and Discussion

Comprehensive analysis of process parameters

Table 1 shows the line deposition experimental results, and Figures 3–5 show the corresponding characterizations. The effect of the process parameters on the formed parts by line deposition is mainly indicated by the morphology of the deposition layer, forming size, and aspect ratio.

FIG. 3.

Cross section of some line deposition (number in the figure corresponds to the number in Table 1).

FIG. 4.

Cross-section diagram of line deposition layer.

FIG. 5.

(a–d) The influence of process parameters on forming size.

Figure 5a–d shows the influence of the process parameters on the size (i.e., width [W], height [H], and depth [H₁] in Figure 4) of the line deposition layer. The width of the AM layer increased gradually with increasing laser power (99–132 W) and decreasing scanning speed (0.6–1.0 mm/s). When the laser power increased and/or the scanning speed decreased, the laser energy density on the same horizontal plane increased, and the laser melted more powder; such that the width increased accordingly. When the focus of the powder beam deviated from the base block (i.e., off-focus), the width of the AM layer changed gradually with off-focus quantity, and the width reached its maximum at the focus of the powder beam.

The powder feeding rate also affected the width of the AM layer, which depended on the characteristics of the LCPF technology. When the powder feeding rate was within the range of 1.4–2.8 g/min, the width of the AM layer increased gradually with increasing powder feeding rate. When the powder feeding rate exceeded 2.8 g/min, the laser energy was substantially scattered during the interactions with the powder. At this moment, only a small portion of the powder absorbed sufficient melting energy to form a solid. Therefore, the width of the AM layer decreased upon exceeding a certain powder feeding rate. Similarly, the deposition height increased with increasing laser power and powder feeding rate, and decreased with increasing scanning speed and focus position of the powder beam (Fig. 5).

In addition, Figure 5 also indicates that the penetration depth was less affected than the other dimensional parameters by the process parameters. When the laser power was changed over the range of 99–132 W, the depth fluctuated between 0.40 and 0.44 mm. When the scanning speed increased from 0.6 to 1.0 mm/s, the depth was between 0.34 and 0.45 mm. When the defocus quantity was −1.0 to 1.0 mm, the change of the penetration depth was not obvious. Finally, although a changing powder feeding rate induced the penetration to fluctuate slightly compared with the other three parameters, the total fluctuation was <0.1 mm; which indicates that the powder feeding rate was not an important factor that affected the penetration depth. In other words, the process parameters mainly affected the width and height of the AM layer, whereas changing the process parameters had little effect on the depth.

In line deposition, the smaller the forming coefficient N [Eq. (2)], the narrower the deposited line and the smoother the line's cross-sectional shape, which might be more conducive to subsequent depositions.

$$N=\frac{H}{W}$$ (2)

The forming coefficient under each process parameter was <1 (Table 1). The silica powder that was used for forming the AM layer was sent vertically downward through the nozzle by nitrogen. Therefore, the forming coefficient was substantially affected by the nitrogen gas flow in the vertical direction, whereas the forming coefficient was negligibly affected by the nitrogen gas flow in the transverse direction. In this manner, the width and height of the AM layer differed substantially. In the line deposition experiments, we observed that an N of ca. 0.5 is more conducive to the stability of AM compared with other N values.

Thus, the influence of the four parameters on the width of the AM layer was as follows: scanning speed > laser power > powder feeding rate > powder beam focus position. The influence on the height of the AM layer was as follows: powder feeding rate > scanning speed > laser power > powder beam focus position. These four parameters had no obvious effect on the depth.

Figures 6 and 7 show analyses and characterizations of the plane deposition density, which are helpful for further screening and optimizing the processing parameters. Regarding plane deposition (single-layer multitracks and single-track multilayer) of LCPF AM, the hatch space and descend height are also important process parameters. Here, the focus is on the influence of the hatch space (0.8–1.2 mm) and descend height (0.6–1.0 mm) on another forming parameter (density) that warrants attention. Other parameters were set as follows: laser power, 110 W; laser scanning speed, 0.8 mm/s; powder feeding rate, 1.4 g/min; and off-focus quantity of powder beam, 0 (N = 0.5 in line deposition). Figure 6 shows the density and apparent porosity of the plane depositions under various hatch spaces.

FIG. 6.

Variation of the bulk density (a) and apparent porosity (b) with laser hatch space in case of 110W laser power.

FIG. 7.

Variation of the bulk density (a) and apparent porosity (b) with descend height in case of 110W laser power.

When the hatch space was between 0.8 and 1.2 mm (descend height: 0.8 mm), the bulk density fluctuated between 2.2003 and 2.2037 g/cm³ (Fig. 6a), close to the density of traditional quartz glass (2.20–2.21 g/cm³). Figure 6b indicates that the apparent porosity fluctuated with increasing hatch space. When the hatch space was 1.0 and 1.2 mm, the apparent porosity reached the minimum (0.11%) and maximum (0.32%) values, respectively. An appropriate hatch space is conducive to the AM continuity, corresponds to a sufficient energy for melting the powder, and enables a small quantity of powder that has not been fully melted to be remelted during secondary heating, which further reduces the porosity.

Figure 7 shows the dependence of the bulk density and apparent porosity on the descend height (hatch space: 1.0 mm). Obviously, the bulk density essentially did not change with the descend height (Fig. 7a), and the apparent porosity decreased initially and then increased with increasing descend height (Fig. 7b). When the descend height was <0.8 mm, the powder beam flow remained in the negative off-focus state. Accordingly, the porosity was large. Until the descend height reached 0.8 mm, the apparent porosity was minimized: ca. 0.17%. Then, with increasing descend height, the powder beam flow gradually changed to the positive off-focus state.

Accordingly, after the powder was ejected, because of the impact of gravity and carrier gas flow, the powder collided with the lower substrate and was not fully melted; resulting in a gradually increasing porosity. The maximum porosity was 0.20%. In summary, with increasing descend height, the porosity of the formed part decreased initially and then increased, in a U-shaped manner.

Performance characterization of bulk deposition

On the basis of the aforementioned analysis of linear and plane deposition, bulk deposition (multilayer multitracks) experiments were performed. In bulk AM, by introducing the combined parameter of the laser energy density (which combines the laser power, laser walking speed, and other parameters), the influence of the process parameters on the thermodynamic properties of printed glass was systematically studied. Furthermore, the internal bubbles as well as the microstructure were characterized and analyzed. The preheating temperature of the substrate was 430°C; Table 2 shows the other process parameters.

Figure 8 shows a physical diagram and the mechanical strength of quartz glass parts under various laser energy densities. Figure 8a–c indicates that within the selected range of laser energy density, the macro morphology was glassy without obvious fine particles, indicating that the powder was fully melted. Figure 8d indicates that the three-point bending strength of the specimen changed with increasing laser energy density. When the laser energy density increased from 171.88 to 214.84 J/mm³, the three-point bending strength of the specimen increased (maximum: 72.36 ± 5.98 MPa). With further increasing laser energy density, the three-point bending strength of the specimen decreased. When the laser energy increased to 286.46 J/mm³, the three-point bending strength reached a minimum (60.69 ± 2.55 MPa).

FIG. 8.

Variations of the bending strength of fused glass sample by additive manufacturing with laser energy density: (a) a glass part fabricated on a fused silica substrate, (b) three-point samples, (c) fracture surface morphology (piece together), (d) three-point bending strength, (e) flexural stress-displacement curve.

The reason for these results is that the powder can be melted well within a certain range of laser energy density; with increasing laser energy density, the higher the melting degree of the powder, the better the combination between various parts, and the mechanical strength is higher. However, when the laser energy density exceeds a certain range, the high temperature reduces the viscosity of the glass, and the small bubbles fuse into large bubbles; resulting in a reduction of the overall bending strength. Figure 8e indicates that during the three-point bending test, the bending stress of each sample increased with increasing displacement load. When the external load increased to a certain extent, the bending stress of the sample reached the limiting value and the sample broke.

Quartz glass is a special glass formed from a single component; as such, its thermal expansion coefficient remains unchanged after forming. Therefore, only the effect of the change of the process parameters on the thermal conductivity of the formed parts was considered in this study. Figure 9 shows the effects of various process parameters on the thermal diffusivity and thermal conductivity of formed parts. Figure 9a indicates that the thermal diffusion coefficient decreased with increasing temperature; furthermore, changing the laser energy density changed the diffusion coefficient to be between 0.79 and 0.93 mm²/s.

FIG. 9.

variation of thermal diffusivity (a) and thermal conductivity (b) with laser energy density.

When the laser energy density was 214.84 J/mm³, the thermal diffusion coefficient was closest (compared with other laser energy densities) to the quartz glass body. The thermal diffusion coefficient of the shaped glass sample was 0.84 mm²/s at room temperature and 0.79 mm²/s at high temperature (450°C). Unlike most metal materials, the thermal conductivity of quartz glass increases with increasing temperature (Fig. 9b). The normal temperature thermal conductivity of the formed part at a laser energy density of 214.84 J/mm³ was 1.35 J/(m·s·°C), which is close to the normal temperature thermal conductivity of commercial quartz glass [1.38 J/(m·s·°C)]. When the test temperature increased to 450°C, the thermal conductivity increased to 1.82 J/(m·s·°C).

As aforementioned, the three-point bending strength of bulk quartz glass made by the LCPF process was ca. 79.23% to 94.49% that of traditional quartz glass under the same conditions, and the thermal conductivity was also slightly lower than that of traditional quartz glass. The thermodynamic properties of the sample are related to its density. Accordingly, to further analyze the causes of the difference between the thermodynamic properties of additive-manufactured quartz glass and traditional quartz glass, the bubbles in the entire sample were measured by ultrasonic measurements; and the micromorphology of a cross section of the sample formed by various parameters was compared. Figure 10a shows a colorized ultrasonic bubble diagram inside the glass sample under various process parameters. There were bubbles inside the sample (Fig. 10a), and the number of bubbles changed continuously with changing process parameters.

FIG. 10.

Color ultrasonic bubble diagram (a) and pore area proportion (b) inside glass sample under different laser energy density.

The thermodynamic properties of the quartz glass samples with few bubbles were better compared with those of the samples with more bubbles, which is consistent with the conclusions drawn from Figures 8 and 9. Figure 10b clearly and intuitively indicates the proportion of bubbles in the glass samples under various process parameters: when the laser energy density was too large or too small, the number of bubbles increased. With increasing laser energy density, small bubbles fused into large bubbles, and the proportion of bubbles increased. Subsequently, the temperature continued to increase, bubbles were eliminated, and the proportion of bubbles decreased to a certain extent. Only when the laser energy density is appropriate was the number of bubbles minimized and its thermodynamic properties optimized.

Figure 11a–o shows an SEM image of a cross section of the formed glass sample under various laser energy densities (171.88, 190.97, 214.84, 245.54, and 286.46 J/mm³). In Figure 11, because of the presence of a small number of bubbles and pores, the combined action of the two defects finally resulted in decreasing mechanical strength and thermal properties. Under various laser energy density parameters, most of the interior of the sample presented a smooth vitrification state (Fig. 11), indicating that the powder was fully melted. When the laser energy density was 171.88 J/mm³, there were many bubbles, and a small quantity of fine particles formed from the incompletely melted powder in the sample.

FIG. 11.

(a–o) The cross-section SEM image of the sample processed by different laser energy density.

Accordingly, the mechanical properties of the glass sample were 85.74% those of commercial quartz glass. With increasing laser energy density, both the number and size of the bubbles decreased, and the mechanical strength increased accordingly. When the laser energy density increased to 214.84 J/mm³, the mechanical strength was the largest (94.49% that of commercial quartz glass). With a continuous increase of the laser energy density, although the density increased, the mechanical properties decreased to 79.23% compared with those of conventional quartz glass. These results are because of the different viscosity of quartz glass caused by a continuous high temperature, which corresponded to partial fusion of the bubbles in the specimen, resulting in different thermodynamic properties.

Conclusions

This article investigated LCPF AM technology for quartz glass. By experiments, the basic parameter optimization, defect generation mechanism, and influence of various laser energy densities were completed. Quartz glass samples with good thermodynamic properties were prepared. The present study will facilitate establishing LCPF as a feasible technique for fabricating quartz glass components for optical, biomedical, and chemical industries. The main conclusions of this article are as follows:

• 1.The four key basic process parameters that affect the geometry and forming quality of line deposition were studied by orthogonal testing. Two parameters—laser scanning speed and laser power—substantially affected the width of the AM layer, whereas the laser scanning speed and powder feeding rate affected the height more than the other characteristics of the material. The plane deposition experiments indicate that the density of the samples that were fabricated by AM reached >99% of the density of the samples prepared by the traditional method when the hatch space and descend height were 1.0 and 0.8 mm, respectively.
• 2.Based on the optimization results of line and plane deposition, the effect of the laser energy density on the properties of cubic glass-forming parts was further analyzed. When the laser energy density varied over the range of 171.88–286.46 J/mm³, the three-point bending strength of the specimen initially increased and then decreased with increasing laser energy density. Analogously, the thermal conductivity of the specimen also fluctuated somewhat with laser energy density. When the laser energy density was 214.84 J/mm³, the number of bubbles in the quartz glass was minimized.

• Accordingly, the mechanical strength of the obtained quartz glass element was maximized: 72.36 ± 5.98 MPa (ca. 95% of the mechanical strength of quartz glass prepared by traditional methods under the same conditions), and the normal temperature thermal conductivity of the formed part under this parameter was 1.35 J/(m·s·°C; close to that of traditional quartz glass). Thus, LCPF AM exhibits substantial potential for fabricating silica glass objects with complex shapes in various contexts.

In the future, additional experiments should be carried out to investigate the influence of the powder particle size on the formation quality. In addition, the resolution of LCPF method as well as the transparency of the sample should be investigated and potentially assessed. Thus, study will help resolve the difficulties in preparing complex structures that consist of quartz glass components by traditional technologies. This study also provides a valuable experimental basis and important reference for optimizing the preparation and further improving the performance of quartz glass components.

Authors' Contributions

M.L.: conceptualization, methodology, experiment operation, data curation, writing-original draft; X.-L.R.: methodology and writing-review and editing; C.H.: technical guidance, experiment operation, and project administration; Z.-Q.C.: test experiment; T.X.: technical guidance; H.-B.Z.: writing-review and editing; Y.-T.C.: conceptualization, methodology, and supervision.

Author Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.