固溶处理及时效制度对7021铝合金组织与性能的影响

Effect of solution treatment and aging system on microstructure and properties of 7021 aluminum alloy

采用电子拉力万能试验机、数字金属电导率测量仪、扫描电子显微镜、数字材料显微镜等设备分析了7021铝合金在不同固溶温度、固溶保温时间及不同时效制度下的组织与性能。结果表明:7021板材的最佳固溶工艺为500℃×120 min,经回归再时效处理(RRA)120℃×24 h+170℃×1 h+120℃×24 h后,合金的抗拉强度为508 MPa、屈服强度为465MPa、断后伸长率为14.0%,电导率为38.9%IACS。

In this paper,the structure and properties of 7021 aluminium alloy under different solid solution temperature,different solid solution holding time and different aging system were analyzed by means of electronic tension universal testing machine,digital metal conductivity measuring instrument,scanning electron microscope and digital material microscope.The results show that the optimum solid solution processes for 7021 aluminium alloy sheet are as follows:the tensile strength of the alloy is 508 MPa,yield strength is 465 MPa,elongation after breaking is 14.0%and conductivity is 38.9%IACS.