紫铜搅拌摩擦焊接工艺研究及接头组织分析

试验研究了板厚为 2 m m和 12 mm的紫铜板的搅拌摩擦焊工艺 ,分析了焊接接头组织及性能。结果表明 ,板厚为 2 mm的紫铜 ,在一较宽的规范范围内 ,可得到组织致密、无孔洞、无裂纹的焊接接头 ,接头强度可达到母材的90 %。板厚为 12 m m时 ,采用双面焊 ,仅中部有未融合的缺陷 ,但缺陷在板厚方向的尺寸小于 1%的板厚 ,大大小于钨极氩弧焊时所容许的缺陷率。焊缝的显微组织为典型的再结晶组织 ,晶粒细小 ,焊缝两侧热影响区的组织不对称。

Study of the Copper Friction Stir Welding Process and Analysis of its Weld Microstructure

mm and 12 mm thick commercially pure copper plates was welded by friction stir welding and the microstructures and properties of the welds were investigated. For 2mm copper plates, a sound weld can be obtained in a wide range of welding parameters, and the weld strength reached 290Mpa, which is 90% of the base metal (300Mpa). For the 12mm copper plates, it is joined from both sides by the weld tool with a pin length of 6mm and there exists un-bonded region in the middle of the weld, the thickness of the un-bonded region is less than 1% of the plate thickness along the thick direction. This defect is much small than the allowable defects in GMAW. The weld microstructure is a kind of recrystalized fine grain, and the morphology of the HAZ on the both sides of the weld is unsymmetric.