异步轧制对Mg-8Li-3Al-0.4Ca合金组织及性能的影响

Effect of Asymmetrical Rolling on Microstructure and Mechanical Properties of Mg-8Li-3Al-0.4Ca Alloy Sheets

本文以Mg-8Li-3Al-0.4Ca合金为研究对象,采用金相(OM)显微组织观察、X射线衍射分析(XRD)、扫描电镜(SEM)、能谱分析(EDS)及力学性能测试的分析方法,获得了此合金在同异速比不同压下量和同压下量不同异速比异步轧制后的微观组织及力学性能。研究结果表明:异速比相同时,随着压下量的增大,α-Mg相和β-Li相逐渐沿轧制方向被拉长成纤维组织,屈服强度和抗拉强度增加,延伸率先减小之后上下波动;压下量相同时,随着异速比的增大,α-Mg相纤维组织被破坏,形成竹节状,β-Li相一直为等轴晶形态,因此,屈服强度和抗拉强度都先增加后减小,延伸率先减小后增加到一个稳定的值。

The microstructure and mechanical properties of Mg-8 Li-3 Al-0.4 Ca alloys after asymmetrical rolling with different reduction rates and different speed ratios were studied by OM, XRD, SEM, EDS and mechanical property testing. The results showed that when the speed ratio was equal, the phases of α-Mg and β-Li were stretched into fiber along the rolling direction as the reduction rates increased. Besides, the yield strength and tensile strength were getting increasing and the elongation reduced firstly then fluctuated. When the reduction rates were unchanged, the phase of α-Mg was broken into bamboo-shaped with the speed ratio increased. Furthermore, the yield strength and tensile strength increased then reduced, and the elongation reduced then increased to a stable value.