稀土氧化物粒子对钼合金粉末冶金过程及力学性能的影响

试验研究了掺杂La2O3、Y2O3、CeO2稀土氧化物颗粒对钼合金的粉末物性、烧结进程、制品的烧结致密度及压力加工丝材的室温力学性能的影响规律。试验结果表明，掺杂稀土氧化物粒子细化了钼粉的粒度，降低了松装密度和粒度分布范围，同时导致粉末团聚现象增多；稀土氧化物粒子延迟了钼合金的烧结进程，降低了烧结制品的致密度，同时细化了烧结体晶粒尺寸。稀土氧化物粒子以弥散强化和细晶强化的形式，提高了钼合金丝的室温强度。CeO2显著提高了钼合金丝的室温韧性，La2O3、Y2O3则降低了钼合金丝的室温韧性。

EFFECTS OF RARE -EARTH PARTICLES ON MOLYBDENUM ALLOY POWDER METALLURGY PROCESSING AND MECHANICAL PROPERTIES

The effects on the molybdenum alloy powder properties, sintering proceeding and sintering products den- sity and mechanical properties of molybdenum alloy as - worked wire which was doped with rare - earth oxides par- ticles such as La2O3 ,Y2O3 ,CeO2 were studied. The results showed that the particles size of the molybdenum alloy powder were refined, loose density and particle size distribution were reduced by doping rare - earth oxides parti- cles, though at the same time molybdenum alloy powder aggregation were increased. Sintering proceeding was de- layed, sintering products density was reduced and the grain size was refined by the rare - earth oxides particles dur- ing sintering process. The room temperature strength of the molybdenum alloy wire as - worked was increased by the grain refinement strengthening and dispersion strengthening of the doped rare - earth oxides particles. Room temperature toughness of molybdenum alloy wire as - worked was greatly improved as doped CeO2 particles but re- duced as doped La2O3 and Y2O3 particles.