论文部分内容阅读
本文先以Ni粉和Al粉为原料,采用机械合金化法合成Ni3Al粉末,再采用粉末冶金法,经1 485℃真空烧结1h后制备出Cr3C2含量不同的Ni3Al粘结TiC基金属陶瓷.研究表明,Ni3Al粘结TiC基金属陶瓷由TiC陶瓷晶粒和Ni3Al粘结相组成,且TiC陶瓷晶粒通常具有芯/环结构.当Cr3C2含量为6％时,具有白芯的小陶瓷晶粒数量明显增多,同时具有黑芯的陶瓷晶粒中白色内环较完整.金属陶瓷的硬度和抗弯强度随着Cr3C2含量增加呈先升高后下降的趋势,断裂韧性随着Cr3C2含量增加先升高随后下降,然后略有上升再下降.当Cr3C2含量为2％时,金属陶瓷具有良好的综合力学性能.“,”Ni powder and Al powder were used to synthesize Ni3Al powder by mechanical alloying,and then Ni3Albonded TiC-based cermets with various Cr3C2 content were prepared by powder metallurgy route,including sintering under vacuum at 1 485℃ for 1 h.The research shows that the Ni3Al-bonded TiC-based cermets are composed of TiC cermet grains and Ni3Al binder phase,and the TiC cermet grains generally exhibit core-rim structure.When Cr3C2 content is 6wt.％,the number of the fine cermet grains with white core increases,and moreover white inner rim in the cermet grains with black core becomes more complete.The hardness and transverse rupture strength of the cermets firstly increase and then decrease with the increase of Cr3C2 content.The fracture toughness of the cermet firstly increases and then decreases,followed by slightly increases and decreases with the increase of Cr3C2 content.When Cr3C2 content is 2.0wt.％,the Ni3Al-bonded TiCbased cermets have good mechanical properties.