【摘要】 测量了用不同Sr加入量变质的近共晶Al Si合金中枝晶α Al的一次分枝间距和二次枝晶臂间距 ,考察了枝晶α Al特征参数的变化对合金力学性能的影响。研究结果表明 :Sr的加入可以细化枝晶 ,表现为一次分枝间距和二次枝晶臂间距随合金中Sr含量的增加而减小 ;枝晶细化可以提高合金的力学性能 ,合金的铸态力学性能与枝晶α Al的特征参数是高度线性相关的更多还原

【Abstract】 The characteristic parameters of dendritic α phase in near-eutectic Al-Si alloys modified with varying strontium, primary dendrite spacing and secondary dendrite arm spacing, were measured and the changes of the mechanical properties with these parameters were considered. Addition of strontium results in a reduction of the primary dendrite spacing and secondary dendrite arm spacing and it leads to an improvement of the mechanical properties. The results of linear simulation illustrate that the mechanical properties as-cast(ultimate tensile strength and fracture elongation) is linearly correlated with the characteristic parameters (λ 1 and λ 2) of dendritic α phase in these alloys.更多还原