Effect of different SiC / TaSi2 contents on ablation behavior of ZrB2 coating

• Published in: Corrosion science 2022-08, Vol.205, p.110424, Article 110424
• Main Authors: Xu, Yixiang, Huang, Shansong, Han, Dijuan, Dai, Meiqi, Zhong, Xin, Niu, Yaran, Zheng, Xuebin
• Format: Article
• Language: English
• Subjects: Ablation behavior; Oxidation; SiC-depleted region; ZrB2-SiC-TaSi2
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2022.110424

In the present work, the ablation behavior of four kinds of ZrB2-based composite coatings with different SiC/TaSi2 contents was evaluated by a plasma flame at 1750-2000 ℃. The types of oxidation products, as well as their formation processes and influence were analyzed based on microstructure characterizations and thermodynamic calculations. The results show that obvious ablation/oxidation-resistance differences of ZrB2-SiC-TaSi2 coatings were detected. The coating of low TaSi2 content was characterized with the disappearance of SiC-depleted region and the formation of a dense intermediate oxide layer, exhibiting better ablation resistance, while the increase of TaSi2 deteriorated the ablation resistance, which conduced to the formation of oxidation layers with loose structure. •The addition of TaSi2 inhibits the formation of SiC-depleted layer and increases the viscosity of liquid phase;•The effect of oxidation products on the ablation performance and structural evolution of coatings were analyzed;•The ablation mechanism of ZrB2-SiC-TaSi2 composite coatings were expounded based on thermodynamic prediction;