7N01-T4铝合金搅拌摩擦焊接头的组织和耐应力腐蚀性能  

Microstructures and stress corrosion resistance of friction stir welded joints of 7N01-T4 aluminum alloy

作　　者：张铁浩[1] 陶传琦[1] 张风东[1] 魏书波[1] 

机构地区：[1]南车青岛四方机车车辆股份有限公司,266111

出　　处：《焊接》2015年第1期37-40,71,共4页Welding & Joining

摘　　要：采用特定的焊接工艺参数对厚度15 mm的7N01-T4铝合金进行了搅拌摩擦焊试验,可获得外观和内部成形好的接头。焊缝在宏观断面中呈"倒钟"形轮廓。焊核区为比母材更细的等轴晶。沿焊缝厚度方向,接头底层的平均显微硬度略高于母材,上层、中层略低于母材。沿焊缝宽度方向,显微硬度由高到低的顺序为TMAZ(RS)>TMAZ(AS)≈WN>BM≈HAZ。采用四点弯曲法对接头进行应力腐蚀裂纹试验(SCC),经过30天周期浸润腐蚀,接头部位未出现腐蚀裂纹,焊缝的腐蚀程度低于母材。15 mm thick 7N01-T4 aluminum alloy butt welds without defect were obtained by friction stir welding with specific welding process parameters.Weld is inverted 'clock' profile at the macro section.The weld nugget grains are finer than that in the base metal.In the weld thickness direction,the average hardness of joint bottom is slightly higher than that of base metal,the average microhardness of the upper and middle section is slightly lower than that of the base metal.In the weld width direction,the microhardness from the highest zone to the lowest zone is TMAZ(RS) >TMAZ(AS)≈WN >BM≈HAZ.SCC experiments were carried out by using four point bending method,no corrosion crack and macroscopic crack were found on sample surface after 30 days of alternating immersion corrosion test,and corrosion degree of weld is lower than that of the base material.

关 键 词：铝合金 搅拌摩擦焊 应力腐蚀 显微硬度 

分 类 号：TG453.9[金属学及工艺—焊接]