稀土元素对AgNi体系改性机理研究

Effect of Rare-earth on Modifying Mechanism of AgNi Alloy

研究了添加微量稀土的银合金触点材料的显微组织、硬度、弯曲次数等,用扫描电子显微镜观察了材料的显微组织和第二相分布。结果发现,添加0.2%稀土能细化晶粒,并以固溶或球状第二相形式存在,可以强化合金,有效延缓材料的回复与再结晶,使材料的抗拉强度上升,断后伸长率提高,材料延性改善,显微硬度趋于均匀,弯曲次数提高。

The microstructure, hardness and deformation degree of silver omamental material after adding rare earth were studied. The microstructure and distribution of the second phase were observed by SEM. The results show that a small amount （0.2%） of rare earth can remarkably flne the grains of silver alloy. The rare earth is distributed in the alloy in the form of solid solution or spherical second phase, which can strengthen the alloy, and delay its recovery and recrystallization. The tensile strength raises, the elongation increases, microhardness is more uniform, extensibility and bending times improve.