含铝量对锌铝合金组织和性能的影响

Effects of Al Content on Microstructure and Properties of Zn-Al Alloy

分析了Zn-5%Al、Zn-15%Al和Zn-27%Al三种锌铝合金的显微组织及其形成过程,测定其流动性、拉伸性和冲击性。结果表明:Zn-5%Al合金的组织为(α+β)片状共晶,Zn-15%Al合金为先共晶α固溶体(转变产物)和(α+β)片状共晶,Zn-27%Al合金组织中没有共晶体,而为α固溶体(转变产物);三种合金中,Zn-5%Al合金的流动性远高于其他两种合金,拉伸时存在明显屈服,伸长率达11.5%;Zn-27%Al合金具有最高的强度和硬度,屈服强度和抗拉强度分别达172.8、271.4 MPa;室温下3种合金的韧性均较低。随冲击温度升高,Zn-5%Al合金的韧性迅速升高,Zn-15%Al合金也有较明显的升高,而Zn-27%Al合金升高幅度不大。

The microstructure of Zn-5%AI, Zn-15%Al and Zn-27%Al alloys were studied and the fluidity, as well as the mechanical properties such as tensile, hardness, ductile were tested. The results show that Zn-5%Al alloy is completely composed of（α＋β）eutectic structure. Zn-15%Al alloy is composed of eutectic and pro-eutectic structure, and Zn-27%Al alloy has no eutectic in its structure, Among three alloys, Zn-5%Al alloy has much better fluidity than that of the others, it has clear yield on its α-ε curve and the elongation up to 11.5%. Zno27%Al alloy has the highest strength and hardness, the offset yield strength is up to 172.8 MPa and the tensile strength is 271.4 MPa. At room temperature,any one of the three alloys has relatively lower impact toughness. With increasing temperature, the impact toughness of Zn-5%Al alloy rises rapidly. The impact toughness ofZn-15%Al alloy rises clearly, but the impact toughness of Zn-27%Al alloy rises little.