中文摘要：

在超高重力场条件下,以B4C-Ti-Ni为反应体系,合成制备TiC-TiB2-Ni复相陶瓷。XRD和FESEM分析结果表明,反应燃烧充分,所得陶瓷基体由TiB2片晶相、不规则TiC相和Ni相构成。燃烧反应放热,促使反应物熔化生成Ti-C-B-Ni液相产物。待反应结束后,TiB2、TiC先后从陶瓷熔体中凝固形核、析出,而Ni相最后凝固,并对陶瓷基体补缩。随着Ni添加量的增加,陶瓷基体显微组织细化,且均质化水平极大提高,同时,陶瓷的相对密度、断裂韧性和弯曲强度逐渐增大,当Ni添加量为20mass%时,陶瓷性能最佳,分别为97.8%、13.1MPa獉m0.5及693MPa。其维氏硬度先升高后降低,当Ni的添加量为15mass%时,达到最高值,为18.6GPa。

英文摘要：

TiC-TiB2-Ni multiphase ceramics based on B4C-Ti-Ni system were prepared by reaction synthesis in the ultrahigh gravity field of1200 g. XRD and FESEM results show that the combustion reaction proceeds completely and Ti C-Ti B2-Ni ceramics are mainly consists of a number of TiB2 primary platelets,irregular TiC secondary grains and a few of Ni phases. It is considered that lots of thermal energy is released during combustion reaction of（ B4C ＋ Ti）,which makes the reactants form the mixed melt of Ti-C-B-Ni. TiC and TiB2 phases firstly nucleate and precipitate from the melt,and Ni subsequently solidifies after combustion reaction,which can effectively improve the relative density of ceramic matrix. The microstructure of multiphase ceramic is clearly refined and presents the improved homogeneity. The relative density,fracture toughness and flexural strength of multiphase ceramic gradually are promoted with increasing the addition amount of Ni,the maximum value of which are 97. 8%,13. 1 MPa·m0. 5and 693 MPa respectively when the addition amount of Ni is 20 mass%.But the Vickers hardness of multiphase ceramic firstly increases then decreases with the increase of Ni. When the addition amount of Ni is15 mass%,the maximum hardness is 18. 6 GPa.