AZ31镁合金轧制变形后组织与性能研究

Microstructure and Mechanical Properties of AZ31 Magnesium Sheet after Hot Rolling

研究了不同轧制变形量和轧制速度对AZ31镁合金板材微观组织和力学性能的影响。轧制变形可显著细化AZ31镁合金板材的晶粒尺寸并提高其综合力学性能。当轧制速度为5 m/min,轧制变形量为50%时,板材平均晶粒尺寸最细可达到9μm,其抗拉强度、屈服强度和延伸率分别提高到280、180 MPa和30%以上,同时探讨了AZ31镁合金屈服强度与晶粒大小之间的关系。在大量AZ31镁合金轧制文献数据和本实验一系列数据的基础上,对比分析了不同轧制工艺对AZ31镁合金综合力学性能的影响。研究表明,本实验所采用轧制工艺可显著提高AZ31镁合金板材的综合力学性能,同时降低板材轧向(RD)和横向(TD)的各向异性。

The effects of rolling reduction and rolling velocity on microstructure and mechanical properties of AZ31 Mg sheets were investigated. Results show that the grain size is significantly refined and the mechanical properties are raised after hot rolling. When the rolling velocity is 5 m/min and the rolling reduction 50%, the average grain size is refined to 9 μm, and the tensile strength, yield strength and elongation are enhanced above 280 MPa, 180 MPa and 30%, respectively. The relationship between grain size and yield strength was also studied. Based on the literatures on AZ31 rolling and experiments in this paper, the comparisons on mechanical properties of AZ31 Mg sheets were carried out. The results reveal that the rolling parameters used in this research can significantly enhance the mechanical properties ofAZ31 Mg sheets, and the anisotropy in transverse direction and rolling direction is not obvious.