掺杂方式对Mo-La_2O_3合金组织和力学性能的影响

Effects of Doping Methods on Microstructure and Mechanical Properties of Mo-La_2O_3

分别采用液-固和液-液掺杂方式向钼粉中引入氧化镧,烧结出Mo-La2O3合金,通过扫描电镜和透射电镜观察,研究了不同掺杂方式制备的Mo-La2O3合金中第二相粒子的粒度分布和形貌,分析了第二相粒子在钼基体中的分布规律,检测了钼丝的拉伸性能,通过位错塞积理论讨论了La2O3颗粒形貌和分布对Mo-La2O3拉伸性能的影响机制。结果表明:液-液掺杂方法能够使钼基体中的La2O3粒子均匀分散,细化La2O3粒径;直径0.6mm、液-液掺杂钼丝的拉伸性能优于液-固掺杂钼丝。

Lanthanum oxide was introduced to molybdenum powder by liquid-liquid doping and liquid-solid doping, respectively. Mo-La2O3 alloys were prepared by powder metallurgy technology. The particle size distribution and feature of doped particles were investigated by SEM and TEM. The distribution of doped particles in matrix was analyzed, the tensile property of the molybdenum alloy wire was tested, the mechanism of the influence of La2O3 particle on tensile property of Mo-La2O3 alloys was discussed by dislocation pile-up theory. The results show that liquid-liquid doping method can refine La2O3 particles and makes them dispersed uniformly in matrix. The tensile property of the molybdenum alloy wire with 0.6 mm diameter liquid-liquid-doped is better than that liquid-solid-dopinged.