摘要
通过剥落腐蚀试验、静态失重分析和动电位极化曲线测试对比研究了搅拌摩擦焊接(FSW)6063铝合金焊缝与母材的腐蚀特性,借助光学显微镜和扫描电子显微镜观察焊缝和母材的微观组织及腐蚀形貌.结果表明:经过48h的腐蚀试验,母材点蚀严重并伴随着局部剥落腐蚀,而搅拌摩擦焊缝没有出现明显的点蚀现象.焊缝的自腐蚀电位比母材高,分别为-666 V和-704 V,焊缝和母材的平均腐蚀速率分别为0.379 g/(m2·h)和2.186 g/(m2·h).在搅拌摩擦焊接过程中,晶粒细化及第二相的均匀分布和减少是焊缝耐蚀性能提高的主要原因.
The 6063 aluminum alloy plates were welded by friction stir welding （ FSW）.The corrosion properties of friction stir welding seams and base materials were studied by the methods of static gravimet-ric , exfoliation corrosion and polarization curves .Their microstructure and corrosion morphology were ob-served by the Optical Microscope （ OM ） and Scanning Electron Microscope （ SEM ） .The results show that：after 48 h corrosion , the pitting corrosion on base materials was serious , and there was partly exfoli-ation corrosion on base materials too .However , the pitting corrosion on welding seams was not obvious after friction stir welding .Furthermore, the self-corrosion potential of welding seams is higher than that of base materials , and they are -666 V and -704 V respectively .The average corrosion rate of the weld-ing seams is far less than that of the base materials , and the value is 0.379 g/（ m2 ＆#183; h） and 2.186 g/（m2＆#183; h） respectively.The small grains and the dissolution at the second phase are primary reasons for the improvement of the corrosion resistance of welding seams during the FSW .
出处
《广东工业大学学报》
CAS
2014年第1期126-130,共5页
Journal of Guangdong University of Technology
基金
广东省重大科技专项资助项目(2008A090300004)
广东省教育厅211工程学科建设项目(412110903)
关键词
搅拌摩擦焊
6063铝合金
焊缝
腐蚀特性
friction stir welding
6063 aluminum alloy
welding seam
corrosion properties
