H62黄铜搅拌摩擦焊接头微观结构及性能  

Microstructure and property of H62 brass joints obtained by friction stir welding

作　　者：宫文彪[1] 毛亚芬[1] 张秋征[1] 王为[1,2] 

机构地区：[1]长春工业大学先进结构材料教育部重点实验室,长春130012 [2]哈尔滨工业大学材料科学与工程学院,哈尔滨150001

出　　处：《焊接学报》2014年第2期83-86,117,共4页Transactions of The China Welding Institution

基　　金：吉林省科技厅高科技资助项目(20100362)

摘　　要：对6 mm厚度的H62黄铜搅拌摩擦焊(FSW)焊缝的微观组织、力学性能进行了研究,测试并比较了焊缝和母材金属的动电位和电阻率在热-力作用下的变化.结果表明,焊缝金属经热和机械力的作用后,焊核区、热力影响区和热影响区的平均晶粒尺寸较母材的35.6μm均有细化,依次为3.8,22.2,30.6μm,反应在力学性能上焊核区硬度最高,拉伸断裂发生在硬度较低的前进侧,在微观断口中存在大量尺寸不均的网状韧窝;焊缝的腐蚀电位较母材有所提高,腐蚀电流密度降低,电阻率高于母材.The 6mm thick H62 brass plate was welded by friction stir welding and the microstructures and mechanical properties of the joints were investigated.Meanwhile,the potentiodynamic polarization and electrical resistivity of the joints were compared to the base metal,respectively.The results show that the welds have finer crystal grains under the thermal and mechanical force.The average grain sizes of weld nugget zone,thermo-mechanically affected zone and heat affected zone were 3.8 μm,22.2 μm and 30.6 μm,respectively.The maximum measure value of weld hardness is in the nugget zone and the fracture of specimens occurred at the advanced side because of lower hardness.Many dimples that had different size can be observed on the tensile fracture surface by SEM.The corrosion potential of the weld was more positive than the one of the base material,and the corrosion current density was less than the one of the parent material.In addition the electrical resistivity of weld exceeds the base material.

关 键 词：H62黄铜 搅拌摩擦焊 力学性能 耐蚀性能 电阻率 

分 类 号：TG407[金属学及工艺—焊接]