SiO_2涂层对TiAl基合金抗高温氧化性能的影响  

Effect of SiO_2 coating on high temperture oxidation resistance of TiAl-based alloy

作　　者：李忠磊[1] 梁伟[1] 滕尚君[1] 马晓霞[1] 赵琦[1] 

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024

出　　处：《材料热处理学报》2008年第5期124-128,共5页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(50171046);高等学校博士学科点专项科研基金(20050112001);山西省自然科学基金(20021051;2006011051)

摘　　要：采用SiO2溶胶-凝胶-旋涂法对TiAl基合金表面进行涂膜。900℃循环氧化测试结果表明,TiAl基合金经SiO2溶胶两次涂膜并热处理后,其抗高温氧化性能得到了显著提高,未涂膜试样氧化一个循环(8h)后增重2.333mg/cm2,涂膜热处理试样氧化40个循环(320h)增重仅为0.6071mg/cm2。XRD和SEM对试样表层的组织结构分析及形貌观察表明,涂层主要由SiO2、Al2O3、Ti5Si3、TiSi2和Ti2Al构成,由表及里分别为SiO2层-Al2O3层-Al2O3+钛硅化合物层-Ti2Al层-TiAl片层组织基体。The sol-gel derived silica films were obtained on TiAl-based alloy by spin coating processing.Cyclic oxidation tests at 900℃ show that the oxidation resistance of TiAl-based alloy is promoted greatly when SiO2 films are coated twice on surface of the alloy after heat treatment.The mass gain of uncoated TiAl-based alloy is 2.333mg/cm after one oxidation cycle（8h）,while the mass gain of the twice-coated one is only 0.6071mg/cm even after 40 oxidation cycles（320h）.The microstructure and morphology of the coated TiAl-based alloy specimens are characterized by XRD and SEM/EDS.The results show that the coatings are composed of SiO2,Al2O3,Ti5Si3＋TiSi2 and Ti2Al,from the outer to the inner.

关 键 词：TIAL基合金 SiO2溶胶凝胶 高温氧化 涂层 

分 类 号：TG174.45[金属学及工艺—金属表面处理] TG146.23[金属学及工艺—金属学]