Microstructure and mechanical properties of A356 thixoformed alloys in comparison with gravity cast ones using new criterion

摘要：

The effect of thixoforming process on morphologies of silicon particles that affect fracture mode of A356 alloy was investigated.Microstructure and fracture surfaces of thixoformed samples were investigated by image analyzing technique and scanning electron microscopy.A new combination parameter,called silicon density ratio (SDR) index,was introduced.SDR index approximates the collective effects of morphological characteristics of silicon particles on microstructure transparency of alloy in crossing the dislocation.It is suggested that samples with lower SDR index have superior mechanical properties,especially elongation,and consequently intergranular fracture mode.On the contrary,samples with higher SDR index have inferior mechanical properties and fracture path tends to propagate along the cell boundaries leading to transgranular fracture.

关键词： A356 thixoforming silicon density ratio microstructure mechanical properties semi-solid forming

作者: A.FADAVI BOOSTANI S.TAHAMTAN

作者单位: Department of Materials Engineering, Isfahan University of Technology(IUT), Isfahan, Iran

会议类型: 国际会议

会议名称: The 11th International Conference on Semi-Solid Processing of Alloy and Composites(第11届合金与复合材料半固态成形国际会议)

会议地点: 北京

会议语种:英文

页码: 1608-1614

在线出版日期: 2010-09-16（万方平台首次上网日期，不代表论文的发表时间）