分流模挤压焊合区域的氧化物分布及焊合组织分析

摘要

利用有限元分析、扫描电子显微镜及金相实验研究分流模的锭接锭挤压条件下,型材纵、横向焊合区域的氧化物分布及焊缝微观组织.结果表明:氧化物仅存在于型材基体与横向焊合区域结合面；纵向焊缝表现为深色条纹状组织,包含在强剪切变形及高温条件下形成的粗大再结晶晶粒中；横向焊缝组织表现为晶粒度略小的等轴再结晶晶粒.%The oxide distribution and microstructure in longitudinal and transverse welding zones during the billet-to-billet extrusion process through porthole die were adequately investigated by means of finite element method,scanning electron microscopy and optical microscopy.The results indicate that the oxides exist at the interface between the matrix and transverse welding zone rather than longitudinal welding seam.The longitudinal welding zone reveals a darker band including the largest grain with irregular shape due to the abnormal grain growth under the heavy shear deformation and high temperature.The transverse welding zone consists of equiaxed recrystallized grains which are a little finer than those in the longitudinal welding seam.