TiB2粒径对BN-TiB2复相陶瓷致密化和性能的影响  

Influence of Particle Size of TiB_2 on Densification and Properties of BN-TiB_2 Composite Ceramics

作　　者：田仕[1] 邢伟宏[1] 王为民[1] 傅正义[1] 王皓[1] 张金咏[1] 

机构地区：[1]武汉理工大学,材料复合新技术国家重点实验室,武汉430070

出　　处：《硅酸盐学报》2011年第11期1757-1762,共6页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(60578041)资助项目

摘　　要：以平均粒径分别为8.1μm和12.2μm的两种TiB2粉末为原料,通过热压烧结方法制备BN–48%(质量分数)TiB2复相陶瓷,研究了TiB2粉末粒径对复相陶瓷致密化和性能的影响。结果表明:平均粒径小的TiB2粉末所制备的复相陶瓷致密化速率更快,致密度更高;在1 850℃烧结1.5 h后,表观相对密度为95.3%,体积相对密度为83.9%,抗弯强度为85.3 MPa,弹性模量为47.2 GPa,电阻率为1.4 m?.cm,673 K时的热导率为33.7 W/(m.K),298～1 373 K的平均热膨胀系数为7.2×10–6/K,均优于相同工艺条件下平均粒径大的TiB2粉末所制备的复相陶瓷的性能。The BN–48%（in mass） TiB2 composite ceramics were fabricated by a hot pressing sintering method using two types of TiB2 powders with the average particle size of 8.1 μm and 12.2 μm,respectively.The effect of particle size of TiB2 powders on the densification and properties of BN–48%TiB2 ceramics was investigated.The results show that TiB2 powder with the smaller size can enhance the densification,leading to a higher density of the samples.After hot-pressed at 1 850 ℃ for 1.5 h under the same processing conditions,the apparent relative density,bulk relative density,bending strength,elastic modulous,resistivity,thermal conductivity （673 K） and mean thermal expansion coefficient（298–1 373 K） of the BN–48%TiB2 ceramics prepared with the finer powder of TiB2 were 95.3%,83.9%,85.3 MPa,47.2 GPa,1.4 m？？cm,33.7 W/（m.K） and 7.2 × 10–6/K,respectively,which were better than those of the samples prepared with the coarser powder of TiB2.

关 键 词：氮化硼-二硼化钛 复相陶瓷 平均粒径 热压烧结 致密化 

分 类 号：TB332[一般工业技术—材料科学与工程]