稀土氧化镧掺杂钼合金的强化机制研究

The Strengthening Mechanism of Rare Earth Lanthanum Oxide Doped Molybdenum Alloys

摘要:

使用粉末冶金工艺制备了不同体积分数稀七氧化镧颗粒掺杂的钼合金。观察了该合金的显微组织并测试了其力学性能。结果表明，稀士氧化镧掺杂钼合金由于其细小的氧化镧颗粒和细小的晶粒的作用而具有较高的屈服强度。对稀士氧化镧掺杂钼合金强化机制的分析结果表明，钼合金的屈服强度主要来源于三个部分：变形前基体强度、细小稀士氧化镧颗粒贡献的强度和细小钼合金晶粒贡献的强度，并给出了稀土氧化镧掺杂钼合金屈服强度与稀土氧化镧颗粒尺寸、体积分数以及晶粒尺寸之间的定量解析关系。

Abstract:

The rare earth lanthanum oxide doped molybdenum alloys containing different volume fraction lanthanum oxide particles were prepared by powder metallurgical processing. The microstructure and mechanical properties of the alloys were examined. It is found that the alloy has the fine lanthanum oxide particles and fine grain as well as high yield strength. The strengthening mechanism of the alloy is analyzed and explained in three aspects: matrix strengthening, fine grain size strengthening yielding Hall-Petch relationship, and fine particles strengthening according to the Orowan model. The quantitative relationships between the yield strengths of the alloys and the sizes, volume fraction of lanthanum oxide particles and the grain sizes were also presented.