Experimental additive manufacturing of green body of SiC/Graphite functionally graded materials by stereolithography

Abstract

Ceramic stereolithography (CSL)-additive manufacturing (AM) technology is used to create a functionally graded ceramic (FGC) green body made of silicon carbide (SiC) and graphite. For the SiC/graphite FGC, the mixing parameters of ceramics powders and ultraviolet (UV) curing resin are improved, and correlations of the resultant slurry curing depth with integrated light intensity are discovered. Therefore, the SiC/graphite FGC-produced green body has no flaws, pores, or cracks on its surfaces. According to the association between cure depth and integrated light density for each slurry's composition, several interfacial collapses discovered in a cracked cross-section might be decreased.

Fabrication of ZTA crowns with simultaneously improved isotropy on mechanical property and surface quality by DLP

“…With an increase in contents of YSZ powders from 5 to 20 wt% in the suspensions, the fracture mechanisms was gradually transferred from intergranular fractures to transgranular fractures, contributing to a higher flexural strength (see Figure 6K,L). 28–30 In addition, as for 3D‐printed sintered ZTA composites, it was observed that grain sizes of alumina notably decreased as content of YSZ powders increased, which was attributed to the restraining effect of fine zirconia particles situated at grain boundaries of alumina grains, which hindered grain growth in alumina 30 . Hence, these findings strongly implied that the grain size of alumina plays a vital role in determining the anisotropy on flexural strength.…”

“…In addition, relative density of 3D‐printed sintered ZTA ceramic parts is shown in Figure 3D. Compared to sintered ZTA composites printed using the model 1 or 2, relative density was lower with respect to ZTA composite ceramic objects printed in the model 3, which might be imputed to the most printing layers and resultant interlayer defects after sintering process 28 . Besides, for sintered ZTA composites fabricated using ceramic suspensions with different contents of YSZ powders added, no obvious difference in relative density could be observed, as shown in Figure 3D.…”

“…With an increase in contents of YSZ powders from 5 to 20 wt% in the suspensions, the fracture mechanisms was gradually transferred from intergranular fractures to transgranular fractures, contributing to a higher flexural strength (see Figure 6K,L). [28][29][30] In addition, as for 3D-printed sintered ZTA composites, it was F I G U R E 7 Field emission scanning electron microscopy (FESEM) micrographs of fracture surfaces for typical sintered Z5 and Z20 composites printed using the three different models.…”

Recent progress in carbide‐based composite materials fabricated by laser additive manufacturing processes

“…Fabricating new composites with this matter by LAM techniques is so limited. Because the other AM methods like stereolithography and direct light processing are more proper than LAM techniques for fabricating composite structures of SiC 51,52 . However, some admirable works have been done by various research groups.…”

“…Because the other AM methods like stereolithography and direct light processing are more proper than LAM techniques for fabricating composite structures of SiC. 51,52 However, some admirable works have been done by various research groups. For example, Wu et al 53 fabricated Si/SiC lattice structures by combining various methods, which can be seen in Figure 16.…”