不同工艺处理后镁钆合金的组织与力学性能  

Microstructure and Mechanical Properties of Mg-9Gd Magnesium Alloys Treated by Different Processes

作　　者：万晓峰[1,2] 倪红军[1] 黄明宇[1] 汪兴兴[1] 吴闵[2] 

机构地区：[1]南通大学机械工程学院,南通226019 [2]东南大学材料科学与工程学院,南京211189

出　　处：《机械工程材料》2012年第11期19-22,57,共5页Materials For Mechanical Engineering

基　　金：江苏省高校自然科学基金资助项目(10KJB430012);南通市应用研究计划项目(BK2011063)

摘　　要：对铸态Mg-9Gd镁合金挤压变形后再进行不同的热处理,研究了不同处理后Mg-9Gd镁合金的组织与力学性能。结果表明:挤压态Mg-9Gd合金的显微组织由大量的细小等轴晶粒和少量中间相组成,中间相破碎成大量细小的块状颗粒,沿平行于应力方向呈带状分布;相比铸态合金,挤压态合金的σ_b提高了89.8%,σ_(0.2)提高了44.1%,δ达到了19.5%;挤压态合金经520℃×2 h+200℃×8 h处理后,强度和塑性降低,σ_b,σ_(0.2)分别为231.4,129.3 MPa,δ为15.2%;经200℃×14 h处理后,挤压态合金的强度明显提高,σ_b,σ_(0.2)分别达到254.2,180.3 MPa,但塑性进一步降低,δ为10.5%。The as-cast Mg-9Gd alloy was extruded, and then was hot treated, the microstructure and mechanical properties of the Mg-9Gd alloy after different treatments were studied. The results show that the extruded alloy contained amounts of refine equiaxed grains and a small number of intermediate phases, and the later was broken to massive block particles along the stress direction distribution in belt. Comparing with the as-cast alloy, the tensile strength （σb） and the yield strength （a0.2） of the extruded alloy increased by 89. 8% and 44. 1% , and the elongation reached to 19. 5%. The σb, σ0.2 decreased after the extruded alloy was treated by 520 ℃ ×2 h＋ 200 ℃ × 8 h, and the σb, σ0.2 were 231.4, 129. 3 MPa, and δ was 15.2%. The aging treatment of 200 ℃× 14 h obviously enhanced the strength, σb and a0.2 up to 254. 2 MPa and 180. 3 MPa, but the plasticity decreased further, and δ was 10. 5 %.

关 键 词：Mg-9Gd合金 挤压 时效 显微组织 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]