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采用低压烧结工艺制备出Ti(C_(0.7)N_(0.3))-WC-Mo_2C-TaC-Fe/Co/Ni体系金属陶瓷,研究了Fe含量对Ti(C,N)基金属陶瓷显微组织、相组成及力学性能的影响。结果表明,随着Fe含量的增加,组织中白芯-灰环结构的硬质相体积分数显著增大,且在固相烧结阶段,大量M_(12)C型η相转化为M_6N型脆性相;高Fe含量的金属陶瓷体系有利于脆性相的生成。力学性能测试结果表明,适量Fe置换Ni可显著提高Ti(C,N)基金属陶瓷的硬度和断裂韧性,并随Fe含量增加呈先升高后降低的变化趋势。当Fe含量为2%时,金属陶瓷的硬度和断裂韧性均达到最大值1 642 MPa和10.63 MPa·m~(1/2),与不含Fe的金属陶瓷相比,分别提高了96 MPa和11.3%。但添加过量Fe反而会极大地恶化金属陶瓷的力学性能,这主要归因于高Fe含量金属陶瓷组织中M_6N型脆性相含量的增加。
The Ti (C_ (0.7) N_ (0.3)) -WC-Mo_2C-TaC-Fe / Co / Ni cermets were prepared by low pressure sintering. The effect of Fe content on the microstructure of Ti , Phase composition and mechanical properties. The results show that with the increase of Fe content, the volume fraction of hard phase in the white core - gray ring structure increases obviously, and during the solid phase sintering, a large amount of η phase of M_ (12) C phase transforms into M_6N type brittle phase ; High Fe content cermet system is conducive to the formation of brittle phase. The results of mechanical properties test show that the appropriate amount of Ni can significantly increase the hardness and fracture toughness of Ti (C, N) -based cermets and increase firstly and then decrease with the increase of Fe content. When the content of Fe is 2%, the hardness and fracture toughness of the cermets reach the maximum value of 1642 MPa and 10.63 MPa · m ~ (1/2), respectively. Compared with the cermets without Fe, the hardness and the fracture toughness of the cermets increase by 96 MPa and 11.3%. However, the addition of excessive Fe will greatly deteriorate the mechanical properties of cermets, which is mainly due to the increase of the content of M_6N brittle phase in the high Fe content cermets.