中文摘要：

采用近液相线铸造法制备出ZL201合金半固态锭坯,并对其进行了触变挤压成形。利用金相显微镜观察了其组织变化,并与常规铸造ZL201合金的组织与挤压成形件的组织进行了对比分析。研究结果表明,半固态合金挤压后组织更细小均匀,消除了宏观偏析、晶内疏松等缺陷。主要原因是在挤压过程中晶粒的变形量、畸变区域很大,故在动态再结晶的过程中,半固态合金组织发生再结晶转变的体积分数大于常规铸造合金组织发生再结晶转变的体积分数。

英文摘要：

The semi-solid ZL201 alloy slurry prepared by near-liquidus casting was thixo-extruded, and microstructure of the thixo-extruded parts was observed and analyzed comparatively with those of con- ventional casting ZL201 alloy parts and squeezing casting parts. The results reveal that microstructure of thixo-extruded parts exhibit fine and uniform with absence of macro-segregation and grain porosities, which are beneficial for improving the mechanical properties of ZL201 alloy parts. During thixo-extruded process, there exist severe grain deformation and distortion zone, leading to recrystallization fraction in semi-solid alloy slurry during dynamic recrystalliztion process higher than that in conventional casting ones, which is responsible for the fine uniform distribution of grain size in thixo-extruded parts