TY - JOUR
T1 - Effect of free silicon content in inner SiC-Si coating on thermal cyclic ablation behaviour and microstructure of ZrC/SiC-Si coating
AU - Feng, Tao
AU - Tong, Mingde
AU - Yao, Shuotian
AU - Li, Hejun
AU - Wen, Shifeng
AU - Lin, Hongjiao
N1 - Publisher Copyright:
© 2020
PY - 2020/7/15
Y1 - 2020/7/15
N2 - To investigate the influence of free silicon content in inner SiC-Si coating to thermal cycle ablation behaviour outer CVD-ZrC coating, SiC-Si inner coatings with different free silicon content were prepared by pack cementation on the surface of carbon/carbon (C/C) composites. These three kinds of coatings are named as PC-5, PC-7.5 and PC-10, of which the inner coatings are prepared with three different raw material powders (mass ration Si:C:Al2O3, PC-5 (5:1:0.5), PC-7.5 (7.5:1:0.5), PC-10 (10:1:0.5)). It can be observed that a gradient distribution tendency exists between the ZrC and SiC layers both in specimens (PC-7.5 and PC-10). Among three kinds of samples, PC-7.5 exhibited the best cyclic ablation resistance. The amount of Zr-Si-O glass on the surface of ablated specimens increases with free silicon content in inner coating. Interestingly, when the Si element in inner coating was excessive, Zr-Si-O glass would exhibit a spherical structure accompanied with the ablation resistance decreasing. Meanwhile convex structure ZrO2 was formed after the ablation process of ZrC/SiC-Si coating. The amount of convex ZrO2 structures gradually decreased with the increase of silicon content. The size of ZrO2 grains increased with the increase of the silicon content or the time of cyclic ablation.
AB - To investigate the influence of free silicon content in inner SiC-Si coating to thermal cycle ablation behaviour outer CVD-ZrC coating, SiC-Si inner coatings with different free silicon content were prepared by pack cementation on the surface of carbon/carbon (C/C) composites. These three kinds of coatings are named as PC-5, PC-7.5 and PC-10, of which the inner coatings are prepared with three different raw material powders (mass ration Si:C:Al2O3, PC-5 (5:1:0.5), PC-7.5 (7.5:1:0.5), PC-10 (10:1:0.5)). It can be observed that a gradient distribution tendency exists between the ZrC and SiC layers both in specimens (PC-7.5 and PC-10). Among three kinds of samples, PC-7.5 exhibited the best cyclic ablation resistance. The amount of Zr-Si-O glass on the surface of ablated specimens increases with free silicon content in inner coating. Interestingly, when the Si element in inner coating was excessive, Zr-Si-O glass would exhibit a spherical structure accompanied with the ablation resistance decreasing. Meanwhile convex structure ZrO2 was formed after the ablation process of ZrC/SiC-Si coating. The amount of convex ZrO2 structures gradually decreased with the increase of silicon content. The size of ZrO2 grains increased with the increase of the silicon content or the time of cyclic ablation.
KW - Ablation behaviour
KW - Chemical vapor deposition
KW - Cyclic ablation
KW - Ultra-high temperature ceramic
UR - http://www.scopus.com/inward/record.url?scp=85083335746&partnerID=8YFLogxK
U2 - 10.1016/j.surfcoat.2020.125775
DO - 10.1016/j.surfcoat.2020.125775
M3 - 文章
AN - SCOPUS:85083335746
SN - 0257-8972
VL - 393
JO - Surface and Coatings Technology
JF - Surface and Coatings Technology
M1 - 125775
ER -