医用镁丝多道次大塑性拉拔变形工艺及微观组织研究

本文以医疗器械行业常用材料纯镁丝为研究对象,采用一种新型大塑性多道次转角拉拔(M-PAD)变形工艺,建立了M-PAD变形模型,并模拟了拉拔过程中纯镁材的等效应力、等效应变变化图;通过设计便于进行拆卸与实验操作的M-PAD模具,对纯镁M-PAD变形工艺参数进行了试验研究。结果表明:M-PAD拉拔变形有利于晶粒的均匀细化,在第1次拉拔后,试样的晶粒得到细化,拉拔2次后晶粒大小无明显变化;M-PAD拉拔过程应选取合适的参数,本次试验得出的最优拉拔参数为4 mm/min速度下进行2次M-PAD拉拔。

Study on Processing Technology and Microstructure of Medical Magnesium Wire with Large Plastic Drawing

In this paper,pure magnesium wire,a commonly used material in medical device industry,was used as theresearch object.M-PAD deformation model was established by using a new large-plastic multi-pass corner drawing(M-PAD)deformation process.The equivalent stress and equivalent strain diagram of pure magnesium wire in the process of drawingwere simulated.The deformation process parameters of pure magnesium M-PAD were analyzed.The results show that thedrawing deformation of M-PAD is conducive to the uniform grain refinement.After the first drawing,the grain size of thesample is refined,and there is no significant change in the grain size after the second drawing.Appropriate parameters shouldbe selected in the M-PAD drawing process.The optimal drawing parameter obtained in this test is to conduct M-PAD drawingtwice at a speed of 4 mm/min.