半固态等温热处理复合挤压对Mg-15Gd-1.7Ni镁合金微观组织及硬度影响  

Effect of Semi-Solid Isothermal Heat Treatment Combined Extrusion on the Microstructure and Hardness of Mg-15Gd-1.7Ni Magnesium Alloy

作　　者：施晓文 刘秋媛 SHI Xiaowen;LIU Qiuyuan(Ji’an Innovation Development Center of Science and Technology Development,Ji’an 343000,China)

机构地区：[1]吉安市科技创新发展中心,江西吉安343000

出　　处：《生物化工》2024年第2期68-71,88,共5页Biological Chemical Engineering

基　　金：江西省教育厅科学技术研究项目(GJJ201006,GJJ201032);吉安市重大科技专项(吉财教指〔2022〕4号)。

摘　　要：半固态等温热处理复合挤压是通过改善镁合金组织结构强化其力学性能的一种重要工艺方法。本文研究不同保温温度和保温时间对Mg-15Gd-1.7Ni镁合金微观组织晶粒尺寸、形貌和液相分数变化的影响,分析铸态直接挤压﹑半固态挤压和半固态处理水淬后挤压3种状态下镁合金的微观组织及硬度。结果表明,经过半固态热处理后的镁合金中的α-Mg相晶粒变得细小、圆整,分布也较为均匀,同时复合挤压工艺改善了硬度在垂直挤压和挤压方向上的不均匀性。Semi-solid isothermal heat treatment combined extrusion is a key method to strengthen mechanical properties of magnesium alloys by improving its structure.In this paper,the effect of holding temperature and time on the grain size,morphology and liquid fraction of Mg-15Gd-1.7Ni magnesium alloy microstructure are studied.Microstructure and hardness of Mg-15Gd-1.7Ni alloy are analyzed under direct extrusion in the as-cast state,semisolid extrusion and water-quenched semi-solid extrusion.The results show that the grains of the α-Mg phase in the semi-solid heat treatment of magnesium alloy become fine,rounded and evenly distributed,and the composite extrusion process improves the inhomogeneity of hardness in the direction of vertical extrusion and extrusion.

关 键 词：镁合金 半固态热处理 挤压 微观组织 硬度 

分 类 号：TG146[一般工业技术—材料科学与工程]