C—SiC—TiC—TiB_2复合材料的抗氧化性能研究  

OXIDATION RESISTANCE OF C-SiC-TiC-TiB_2 COMPOSITE

作　　者：黄启忠[1] 肖汉宁[2] 杨巧勤[2] 

机构地区：[1]粉末冶金国家重点实验室,长沙410083 [2]湖南大学材料科学与应用化学研究所,长沙410082

出　　处：《粉末冶金材料科学与工程》1998年第3期211-215,共5页Materials Science and Engineering of Powder Metallurgy

基　　金：国家自然科学基金

摘　　要：对原位反应合成的C-SiC-TiC-TiB_2复合材料在600～1200℃空气中的抗氧化性能进行了研究。在不同材料组成和试验温度下,试样分别出现氧化增重和失重,这主要取决于碳相和陶瓷相的氧化速率及氧化层的结构特征。在600℃该材料几乎不被氧化;800℃时TiB_2被优先氧化,形成B_2O_3液相;在1000℃以上B_2O_3与SiO_2生成硼硅酸盐玻璃,形成一致密氧化层。氧化过程中液相的出现和致密氧化层的形成显著降低了氧化速率,使材料进入钝氧化,表现出优良的抗氧化能力。Oxidation resistance of C-SiC-TiC-TiB_2 composite prepared by in-situ synthesis was conducted from 600 to 1200 ℃ in air. Both mass gain and loss occurred by the difference of composition and testing temperature. The mass change essentially depends on the oxidation ratio of carbon and ceramics, and the characteristics of oxidized surface. The composite was hardly oxidized at 600 ℃. TiB_2 was first oxdized and B_2O_3 liquid formed at 800 ℃. B_2O_3 and SiO_2 trend to form a borosilicate glass above 1000 ℃ ,which lead to a formation of dense oxide surface. The oxidation ratio was obviously decreased by the appearance of liquid phase and the formation of dense oxide surface during oxidation. This makes the oxidation mechanism of the composite into blunting oxidation ,resulting in excellent oxidation resistance.

关 键 词：碳/陶复合材料 抗氧化性能 

分 类 号：TB332[一般工业技术—材料科学与工程]