坯料温度对AZ31镁合金反挤成形的影响  

Effect of Billet Temperature on the Backward Extrusion of AZ31 Mg Alloy

作　　者：王强[1] 张治民[1] 

机构地区：[1]中北大学材料科学与工程系,太原030051

出　　处：《材料工程》2006年第z1期310-312,316,共4页Journal of Materials Engineering

基　　金：山西省青年科学基金资助项目(20051022)

摘　　要：在300～400℃温度范围内,挤压比λ=5的条件下,对铸造态AZ31镁合金的反挤压成形进行了实验研究,分析了挤压变形力、挤压成形性以及组织性能的变化规律.实验结果表明:AZ31镁合金在300～400℃范围内反挤成形,随变形温度的升高,挤压变形力呈现下降的趋势;而△T(坯料温度的不均匀度)的增大,使得挤压件表面质量变差,外表面出现垂直于挤压方向的横向裂纹;随变形温度的降低,挤压件晶粒逐步细化,硬度上升.为AZ31镁合金反挤压变形温度的优化提供了基础.The backward extrusion operation were carried out in the temperature range of 300~400℃ and extrusion ratio of 5 for as-cast AZ31 magnesium alloy.The effects of billet temperature on deformation force、formability、microstructure and mechanical properties of extrusions have been investigated.It was found that the peak load reduces as the billet temperature is higher from relation between press and displacement.As the ΔT value increases,surface quality extrusion formabilities decreases result in cross crack appearance perpendicular to the extrusion direction.As the billet temperature decreases,the grain size of the extrusion becomes smaller.As the result,the hardness of the extrusion increases.In order to produce increased formability and improved properties,it is necessary to optimise the temperature distribution in the extrusion process.

关 键 词：AZ31 镁合金 反挤压 变形温度 

分 类 号：TG146[一般工业技术—材料科学与工程]