【摘要】 采用连续挤压技术制备了Sn-58Bi合金丝,并对连续挤压过程中的组织及性能演变进行了研究。结果表明,在摩擦剪切变形区,Sn相沿变形方向被拉长,Bi相呈带状分布;镦粗区的Bi相呈粗大团状分布;粘着区开始发生动态再结晶,Bi相呈蔷薇状分布;直角弯曲挤压区发生完全动态再结晶,形成了细小的再结晶组织。在连续挤压过程中,Sn-58Bi合金的显微硬度总体呈上升趋势。合金丝的抗拉强度和伸长率均随着挤压比的增大而增大。研究表明Sn-58Bi合金的断裂主要是由Sn相和Bi相之间的相界分离和Bi相破碎引起的。更多还原

【Abstract】 The Sn-58Bi alloy wires were fabricated by continuous extrusion technology.The microstructure and property evolution of the Sn-58Bi alloy during continuous extrusion were researched.The results showed that Sn matrix was elongated along the extrusion direction and the Bi phase was in band-like distribution in friction-shearing region.The Bi phase seems like coarser cluster structure in the upsetting deformation region.The dynamic recrystallization began to occur and Bi phase turns into rosette structure in the adhesion region.The dynamic recrystallization was completed and resulted in finer recrystallization structure in the right-angle bending region.The Vickers hardness of Sn-58Bi alloy increased with the increasing deformation during continuous extrusion except in the right-angle bending region.The tensile strength and elongation of alloy increase with the increase of the extrusion ratio.Analysis has indicated that the fracture of Sn-58Bi alloy wire was caused by inter-phase separation between the tin and bismuth phase and broken of bismuth.更多还原