轧制变形量对Al-5Zn-3Mg-1Cu合金显微组织和力学性能的影响

Effect of Rolling Deformation on Microstructure and Mechanical Properties of Al-5Zn-3Mg-1Cu Alloy

采用室温拉伸试验、Kahn撕裂试验,结合光学显微镜、透射电子显微镜等方法,研究了Al-5Zn-3Mg-1Cu铝合金厚板在热轧过程中随轧制变形量增大其合金组织和力学性能的演变过程.结果表明:热轧变形过程中,变形量从56%增大至91%时,合金的再结晶分数由0.49%增大至43.30%,晶粒尺寸从83μm减小至10μm以下,合金的抗拉强度和屈服强度分别从542.3和520.0 MPa提升到593.4和564.9 MPa,延伸率从8.0%左右提高到11.2%;随轧制变形量的增大,合金撕裂强度和单位面积裂纹形核功呈增大的趋势.

Tensile test at room temperature and Kahn tear test were conducted to investigate the evolution of the microstructure and mechanical properties of Al-5Zn-3Mg-1Cu thick plate during the hot rolling by means of OM and TEM. The results show that( 1) during the hot rolling of the aluminum alloy,both the deformation and the fraction of recrystallization increase respectively from 56% and 0. 49% to 91% and 43. 30%,while the grain size decreases from 83 μm to below 10 μm;( 2) meanwhile,the tensile strength and yield strength of the aluminum alloy increase respectively from 542. 3 and 520. 0 MPa to 593. 4 and 564. 9 MPa,and the elongation increases from about 8. 0% to11. 2%; and( 3) as the deformation increases,the tear strength( TS) and UIE of the aluminum alloy tend to increase.