(中國(guó)科學(xué)院 金屬研究所 沈陽材料科學(xué)國(guó)家(聯(lián)合)實(shí)驗(yàn)室，
沈陽 110016)
摘 要: 采用固體粉末包埋法在Ti3SiC2陶瓷上滲硅，研究了滲硅涂層的抗高溫氧化性能，用XRD及SEM/EDS分析了滲硅涂層及其氧化后產(chǎn)物的成分、結(jié)構(gòu)和形貌等。結(jié)果表明：滲硅層主要由TiSi2和SiC組成，在空氣中氧化時(shí)形成了SiO2和TiO2的混合氧化物膜。滲硅樣品在1100℃和 1200℃下的恒溫氧化速率比Ti3SiC2降低了2～3個(gè)數(shù)量級(jí)，1100℃下抗循環(huán)氧化性能也優(yōu)于Ti3SiC2。但由于滲硅層中存在裂紋，循環(huán)過程中當(dāng)裂紋貫穿整個(gè)滲硅層時(shí)，涂層的氧化速度開始增加，其保護(hù)作用逐步退化。在1100℃下空氣中循環(huán)氧化時(shí)，經(jīng)400次循環(huán)后涂層已基本失效。
關(guān)鍵字: 鈦碳化硅；滲硅；高溫氧化；涂層
coatings on Ti3SiC2-based ceramic
（Shenyang National Laboratory for Materials Science，
Institute of Metal Research，The Chinese Academy of Sciences，
Shenyang 110016, China）
Abstract:Silicide coating was prepared on Ti3SiC2 base ceramic by pack cementation. The microstructure，phases and oxidation resistance of the coating were investigated. The results show that, the silicide coating is mainly composed of TiSi2 and SiC; one layer of the mixture of SiO2 and TiO2 is formed when the coating is oxidized. At 1100℃ and 1200℃，the oxidation rate of silicide coating is 2～3 order lower than that of Ti3SiC2. The cyclic oxidation resistance of the coating is much higher than that of Ti3SiC2. There are a great number of fine cracks in the outer layer of the coating. When these cracks penetrate whole coating during the cyclic oxidation，the oxidation rate begins to increase，which is the main reason for the loss of the protection of coating.
Key words: titanium silicon carbide ceramic; silicidation; oxidation; coating
