稀土氧化物纳米掺杂对钼合金丝力学性能的影响

摘要

Mo-La, Mo-Y and Mo-Ce nano-composite powders were obtained by nano solid-liquid doping. These three kinds of ?1.8 mm rare earth doped molybdenum wires were prepared by the same pressing, sintering and drawing process. The mechanical properties of these three molybdenum wires were tested at the room temperature and 1 500℃. The toughening mechanism of different rare earth oxides on molybdenum wires were analyzed by TEM. The results show that the molybdenum wires with CeO2 shows best high mechanical property, which was attributed to the deformation of CeO2 particle in the alloy wires. While the La2O3 and Y2O3 particles were not deformed during drawing, which were mainly due to the influence of oxide dispersion strengthening particle. The molybdenum wires with La2O3 shows better mechanical property than that with Y2O3, which was attributed to the particle size and distribution of the second phase in molybdenum wire.%稀土掺杂可提高钼合金的强度，试验通过固-液纳米掺杂获得不同含量的Mo-La、Mo-Y、Mo-Ce复合粉末，经过相同的压制、烧结、拉丝工艺制备了直径为1.8 mm三种不同稀土掺杂钼合金丝。通过对钼合金丝室温及1500℃高温力学性能检测，结合金相及透射电镜分析，研究了不同稀土元素对钼合金丝力学性能的影响，分析其强韧化机制。结果表明：由于CeO2在钼合金丝加工过程中与钼基体一同产生了形变，由此产生的韧化效果，使得钼合金丝表现出更为优异的力学性能；而La2O3与Y2O3在加工过程中并未发生变形，主要起到弥散强化的作用；纳米La2O3因其颗粒分布更为细小均匀，使得La2O3掺杂比Y2O3掺杂的钼合金丝表现出相对高的综合力学性能。