摘要
研究了不同挤压比对铸态Mg-5.4Zn-0.3Zr-0.98RE镁合金微观组织和力学性能的影响。研究表明,当挤压比较小时,微观组织呈现出粗晶和细晶组成的混晶组织;随着挤压比增加到16,微观组织发生完全再结晶,获得均匀、细小的再结晶组织。动态再结晶是铸态镁合金Mg-5.4Zn-0.3Zr-0.98RE晶粒细化的机制。在挤压温度为250℃,挤压比为16时,合金获得的力学性能最好,抗拉强度为345 MPa,屈服强度为223 MPa,断后伸长率为21.4%。
Influences of extrusion ratios on microstructure and mechanical properties of as cast Mg 5.4Zn-0. 3Zr-0. 98RE magnesium alloy were investigated. The results show that the microstructure is composed of coarse unrecrystallised grains and fine recrystallised grains when the extrusion ratio is low. When the extrusion ratio is increased to 16, complete recrystallisation occurs. Fine and homogeneous recrystallised grains are obtained. Dynamic recrystallisation is main mechanism of grain refine ment for as-cast magnesium alloys. When the extrusion temperature is 250 ℃ and the extrusion ratio is 16, the best mechanical properties are obtained. The ultimate tensile strength, yield strength and elongation to fracture are 345 MPa, 223MPa and 21. 4%.
出处
《精密成形工程》
2011年第5期39-42,共4页
Journal of Netshape Forming Engineering
基金
国防基础科研重点项目(D1020060945)
关键词
镁合金
微观组织
力学性能
magnesium alloy
microstructure
mechanical properties
