Effect of PyC-SiC double-layer interface on ablation behaviour of impacted CVD-SiCnws/HfC coating

• Published in: Corrosion science Vol. 191; p. 109741
• Main Authors: Tong, Mingde, Fu, Qiangang, Liang, Mingyu, Feng, Tao, Hou, Wanbo, Sun, Jia, Shi, Xinhao
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.10.2021; Elsevier BV
• Subjects: Ablation; Coating; Core-shell structure; Hafnium carbide; HfO2 precipitation; Hydrofluorocarbons; Impact resistance; Impacting; Interface; Oxidation; Silicon carbide; Ultrahigh temperature ceramic; Impacting; Ultrahigh temperature ceramic; HfO2 precipitation; Ablation; Interface
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2021.109741

•Nano scale PyC-SiC double layer interface was introduced into SiCnws reinforced HfC based thermal protective coating.•The impact-ablation resistance of SiCnws/HfC coating was optimized a lot after introducing PyC-SiC double layer interface.•The self-sealing phenomenon of Hf-Si-O glass and precipitation of nano HfO2 grains could fill the damaged position of outer HfO2 layer. To optimize the impact-ablation resistance of SiCnws@PyC/HfC coating, PyC-SiC double-layer interface phase was introduced. After impacting test, the crack widths of SiCnws@PyC-SiC/HfC were much lower than that of SiCnws@PyC/HfC coating. The impact-ablation resistance of SiCnws@PyC-SiC/HfC coating was better than that of SiCnws@PyC/HfC coating. The good impact-ablation resistance SiCnws@PyC-SiC/HfC coating attributed to the two-grade pull-out reinforcement effect, self-sealing function of Hf-Si-O glass generated from oxidation of SiCnws@PyC-SiC core-shell structure and the precipitation of HfO2 grains from Hf-Si-O glass under ablation environment.