铝硅合金硅相演变及其对力学性能的影响

Evolution of Si Phase in Al-Si Alloy and Its Effect on Mechanical Properties

用SEM观察Al Si合金中富硅相在固溶过程中形貌的演变。结果表明 :固溶初期 ,硅相发生缩颈、钝化、溶断并伴随长大 ;随后硅相的长大是受扩散控制的粗化过程 ,且符合LSW粗化模型 ;固溶后期 ,硅相形貌恶化并出现棱角小面和搭接特征。通过定量金相测量及回归分析 ,硅相的形态对合金的力学性能影响显著。

The evolution of Si phase in Al Si alloy during solid solution treatment has been observed by SEM. The results showed that Si phase undergoes necking, stubbing, fragmentation and growth in the initial stage; and then the growth of Si phase is a coarsening process controlled by diffusion and follows LSW model; the morphology of Si phase deteriorates due to the occurrence of facets and lap in the final stage. The morphology of Si phase has a remarkable effect on mechanical properties of Al Si alloy by quantitative metallographical measurement and regression analysis.