Cu-20Ag合金线材多道次连续拉拔成形及组织演变

Multi-pass continuous drawing forming and microstructure evolution of Cu-20Ag alloy wire

为获得合理的Cu-20Ag合金线材连续拉拔工艺及综合性能更为优异的线材质量,基于Deform有限元软件对Cu-20Ag合金线材多道次连续拉拔过程进行了数值模拟研究,获得了等效应力和等效应变的分布信息,利用点追踪功能分析了多道次连续拉拔过程中线材芯部沿径向到圆周表层的应力和应变的变化情况。并对通过多道次连续拉拔实验制备得到的线材进行了显微组织和断口形貌分析,获得了合金的组织演变规律。结果表明:Cu-20Ag线材表层金属的变形程度比芯部更为剧烈,且随着拉拔道次的增加,线材纵截面各处的等效应力和等效应变值都不断增大。经过多道次连续拉拔,线材纵截面的连续纤维组织近似完全平行于轴向,组织间距逐渐变小且越来越密集,线材组织的细化和均匀化程度也得到了明显增加。

To obtain reasonable continuous drawing process of Cu-20 Ag alloy wire and better wire quality,the multi-pass continuous drawing process of Cu-20 Ag alloy wire was numerically simulated based on Deform finite element software,and the distribution information of equivalent stress and equivalent strain was obtained.The change of stress and strain from the core of wire along the radial direction to the surface of circumference in the multi-pass continuous drawing process was analyzed using the point tracking function.The microstructure and fracture morphology of the wire obtained by multi-pass continuous drawing experiment were analyzed,and the microstructure evolution of alloy was obtained.The results show that the deformation degree of the surface metal for Cu-20 Ag wire is more severe than that of the core metal,and with the increase of drawing pass,the equivalent stress and equivalent strain in the longitudinal section of wire increase continuously.After multi-pass continuous drawing,the continuous fiber structure in the longitudinal section of the wire is approximately parallel to the axial direction completely,the spacing of fiber structure gradually becomes smaller and denser,and the degree of refinement and homogenization of the fiber structure also increases significantly.