A7N01P-T4铝合金激光-MIG复合焊接头微区性能

Micro-zone performance of laser-MIG hybrid welded A7N01P-T4Al alloy joints

以高速列车用14 mm A7N01P-T4铝合金为研究对象,对其激光-MIG复合焊接头的焊缝(WM)、热影响区(HAZ)两个微区以及母材(BM)进行微区拉伸、断裂韧度等性能测试,并结合金相、断口扫描等分析该种接头各区及母材的性能差异.结果表明,A7N01P-T4铝合金母材的抗拉强度最高,其次为激光-MIG复合焊接头热影响区,焊缝最差;接头热影响区的断裂韧度Jm(14)值最高,约为119.580 k J/mm2,其抵抗裂纹扩展的能力是3个区域中最强的;Shapiro-Wilk正态性检验表明,A7N01P-T4铝合金激光-MIG复合焊接头的断裂韧度测试结果具有较高的可靠性.

Laser-MIG hybrid welded joint of 14 mm A7N01P-T4 Al alloy for high speed train was investigated,the properties of WM( weldmetal),HAZ( heat affect zone) of joints and BM( base metal) were tested respectively,such as microzone tensile property,fracture toughness and so on,and the differences of micro-zone properties were analyzed by OM and SEM. BM has the best micro-zone tensile strength,while that of WM is the lowest. HAZ has the highest fracture toughness Jm( 14),which can reach up to 119. 580 kJ /mm2 and indicatesan outstanding ability to resist crack growth in hybrid welded joints.Shapiro-Wilk normality test showed that fracture toughness of laser-MIG hybrid welded A7N01P-T4 Al alloy joints is extremely reliable.