Al-3P和Al-5Ti复合变质共晶铝硅合金的组织与性能

Microstructure and mechanical properties of eutectic Al-Si alloy modified by Al-3P and Al-5Ti

采用Al-3P和0.2 mass%Al-5Ti对共晶铝硅合金进行复合变质处理,并对复合变质前后共晶铝硅合金的显微组织和力学性能进行了分析和测试。结果表明,Al-3P加入量和变质处理温度对共晶铝硅合金的显微组织和力学性能有明显影响。在700℃下采用0.6 mass%Al-3P和0.2 mass%Al-5Ti对共晶铝硅合金进行复合变质处理时,α-Al相体积分数可达到55%,初生α-Al相呈细小枝晶状,硅相呈细小颗粒状。与0.2 mass%Al-5Ti变质处理合金相比,复合变质处理后共晶铝硅合金的抗拉强度和伸长率分别提高28.3%和56.7%,综合力学性能得到明显提高,且其拉伸断口呈现明显的韧性断裂。

Al-3 P and 0.2 mass%Al-5 Ti were used to modify eutectic Al-Si alloy,and microstructure and mechanical properties of the eutectic Al-Si alloy before and after compound modification treatment were analyzed and tested.The results show that the Al-3 P addition amount and the modification temperature have obvious influence on the microstructure and mechanical properties of the eutectic Al-Si alloy.When the eutectic Al-Si alloy is modified with 0.6 mass%Al-3 P and 0.2 mass%Al-5 Ti at 700℃,the volume fraction ofα-Al phase can reach 55%,the primary phase shows fine dendritic and the silicon phase shows fine granular.Compared with the alloy modified with 0.2 mass%Al-5 Ti,the tensile strength and elongation of the eutectic Al-Si alloy after compound modification treatment increase by 28.3%and 56.7%,respectively,the comprehensive mechanical properties are obviously improved,and the tensile fracture surface shows obvious ductile fracture.