A new double layer oxidation resistant coating based on Er2SiO5/LaMgAl11O19 deposited on C/SiC composites by atmospheric plasma spraying

• Published in: Surface & coatings technology Vol. 219; pp. 101 - 108
• Main Authors: Zou, Binglin, Khan, Zuhair S., Fan, Xizhi, Huang, Wenzhi, Gu, Lijian, Wang, Ying, Xu, Jiaying, Tao, Shunyan, Yang, Kuiyue, Ma, Hongmei, Cao, Xueqiang
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 25.03.2013; Elsevier
• Subjects: Applied sciences; Atmospherics; C/SiC composites; Coating; Corrosion; Corrosion environments; Cross-disciplinary physics: materials science; rheology; Deposition; Exact sciences and technology; Failure mechanism; Failure mechanisms; Materials science; Metals. Metallurgy; Oxidation; Oxidation resistance; Physics; Plasma spraying; Production techniques; Silicon carbide; Surface treatment; Surface treatments; Thermal cycling; Failure mechanism; Oxidation; Coating; Thermal cycling; C/SiC composites; Plasma; Hot spraying; Thermal cycle; Surface treatments; Coatings; Mechanism; Corrosion resistance; Silicon carbide; Composite materials; Plasma arc spraying
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2013.01.011

A new coating with Er2SiO5 as inner layer and LaMgAl11O19 (LMA) as top layer was designed and deposited on C/SiC composites by atmospheric plasma spraying to improve the oxidation resistance of the substrate at high temperature. Microstructure, oxidation protection and failure mechanism of the Er2SiO5/LMA coating during dynamic thermal cycling (DTC) were investigated. The results showed that a good interfacial bonding between the substrate and the coating was present before and after DTC test. Weight loss for the sample coated on one-side was 4.5% after 11cycles of heating for 85min, and for the uncoated sample was as high as 20.6%. Failure mechanism of the coating resulted from the liquid sintering of the coating and the formation of bubbles between the substrate and the coating. ► A new Er2SiO5/LMA coating was designed and fabricated on C/SiC composites by APS. ► Microstructure, oxidation protection and failure of the coating were investigated. ► The coating significantly improves the oxidation resistance of substrate at 2273K. ► The sintering of the coating and formation of bubbles make the coating fail.