原位合成NiAl(FeAl)/TiB_2+Al_2O_3复合材料  

In-suit synthesis of NiAl(FeAl)/Al_2O_3+TiB_2 composites

作　　者：崔洪芝[1] 黑鸿君[1] 谢艳春[1] 曹丽丽[1] 

机构地区：[1]山东科技大学材料科学与工程学院,山东青岛266510

出　　处：《粉末冶金技术》2009年第1期33-35,44,共4页Powder Metallurgy Technology

基　　金：国家高技术研究发展计划项目(2006AA06Z381)

摘　　要：Al2O3+TiB2复相陶瓷材料具有高硬度、高熔点、高导热、低膨胀系数、高耐磨性、高温化学稳定性等优良的性能,但由于两种材料都属于硬而脆的材料,复合后仍然存在脆性大、裂纹敏感性强、抗机械冲击性和温度急变形差等缺点。为了克服这些缺点,在陶瓷相中添加金属间化合物(NiAl或FeAl)。X射线衍射结果表明,合成产物的主要组成相分别为Al2O3+TiB2、Al2O3+TiB2+NiAl及Al2O3+TiB2+FeAl,进行燃烧合成反应。通过对不同成分反应产物的相对密度、强度、断裂韧度对比,可知产物的相对密度在FeAl含量为15%时达到最高99.5%,Al2O3+TiB2+NiAl体系中在NiAl含量为20%时达到最高98.5%。随着金属间化合物含量的增加,合成复合材料的硬度下降,而断裂韧度提高。Al2O3＋ TiB2 composite ceramic materials have much more excellent performances： high hardness, high melting-point, high-thermal conductivity, low-expansion coefficient, highwearing resistance and pyrochemistry stability and so on, which metal material is unable to achieve. But both of them belong to hard brittle materials, they still have some shortcomings, just as high brittleness, strong crack-sensitivity, weakness in mechanical impact properties and temperature deformation. In order to overcome these shortcomings, NiAI and FeAl intermetallic compounds were added to the composite ceramics. Results of the XRD show that, Al2O3 ＋ TiB2, Al2O3 ＋ TiB2 ＋ NiAl and Al2O3 ＋ TiB2 ＋ FeAl are the major phase composition. By comparing the density, hardness and fracture toughness of the reaction products, the tiptop of the density is 99.5 % when the content of FeAl is 15 %, while it is 98.5 % when the content of NiAl is 20 % . The more content of NiAl and FeAl intermetallic compound, the lower hardness and the higher fracture toughness of the synthetical composites.

关 键 词：自蔓燃高温合成 Al2O3+TiB2复相陶瓷 金属间化合物 NIAL FEAL 

分 类 号：TQ174.758[化学工程—陶瓷工业] TB33[化学工程—硅酸盐工业]