【摘要】 利用不同凝固速率和等通道挤压法制备不同组织结构的Sn3．8Ag0．7Cu合金,使其包含不同形貌、大小及分布的Ag3Sn金属间化合物;拉伸曲线的比较分析和变形后组织的电镜观察表明,大的针状化合物对合金起着纤维增强的作用,但自身脆性断裂造成空洞,降低了材料的塑性;微细颗粒状化合物起着弥散强化作用,分布在小的等轴晶粒晶界上的化合物颗粒能够阻碍晶界的滑动,起到增强的作用．更多还原

【Abstract】 Sn3．8Ag0．7Cu alloys containing Ag3Sn intermetallic compound (IMC) With different morphologies,sizes and distributions were prepared by controlling cooling rate during solidification and equal channel angle pressing process (ECAP)．The relation between mechanical property of the alloys and IMC phase was investigated．The tensile stress-strain curves of the alloys with different microstructures were compared and the deformed microstructures were observed by SEM and TEM．While the 1arge needle-like Ag3Sn was found to provide fiber-strengthening effect to the alloy,its brittle fracture promoted void nucleation,resulting in a deterioration of tensile elongation. The fine particles of Ag3Sn produced by ECAP enhanced dispersion strengthening by blocking the dislocation motion．The particles on the boundaries of fine equiaxed Sn grains inhibited the boundary sliding, leading to improvement of the tensile strength．更多还原