Mn对Mo_2FeB_2基金属陶瓷组织和力学性能的影响

Effects of Mn on structure and mechanical properties of Mo_2FeB_2-based cermets

以Mo、Fe、FeB和Mn等为原料,采用反应烧结法制备Mo2FeB2基金属陶瓷。利用SEM、EDS和XRD等技术对金属陶瓷显微组织、物相和微区合金元素进行分析,并采用固体与分子经验电子理论研究Mn对脆性第三相以及粘接相对硬质相润湿性的影响。结果表明:添加少量Mn使第三相各键的共价电子对数nα均得到提高,从而改善其脆性;同时Mn也降低液相形成温度,提高粘结相对硬质相的润湿性。因此,Mo2FeB2基金属陶瓷具有较好的力学性能。

Using Mo, Fe, FeB and Mn powders as raw materials, Mo2FeB2-based cermet was prepared by reaction sintering process.The microstructure was characterized by SEM, EDS and XRD.According to the empirical theory of solid and molecule, the influence of Mn on the third phase and wettability of the formed liquid phase was studied.The results show that the brittleness of third phase is improved by increasing nα values for the covalent bonds with Mn addition.Meanwhile, the wettability of hard phase by binder phase is improved.Consequently, Mo2FeB2-based cermet has higher mechanical properties.