【摘要】 采用微弧氧化技术在5083铝合金搅拌摩擦焊接头表面制备一层均匀的陶瓷膜。通过扫描电镜(SEM)、X射线衍射(XRD)和显微硬度测试分析了微弧氧化膜的形貌、相组成和显微硬度,并采用浸泡方法研究了微弧氧化膜对焊接接头耐腐蚀性能的影响。结果表明,接头表面微弧氧化膜均匀致密,铝合金焊缝区的显微硬度低于母相区,但微弧氧化膜的硬度比铝合金基体提高一个数量级,并且不同区域对应的微弧氧化膜硬度相同。在0.2 mol/L NaHSO3+0.6 mol/L NaCl溶液中浸泡3天后,未氧化处理的焊接样品表面出现孔蚀,而微弧氧化处理的样品表面没有观察到腐蚀迹象。更多还原

【Abstract】 A ceramic coating on friction stir welding(FSW) joint of 5083 aluminum alloy was prepared by micro-arc oxidation(MAO) method.Morphology,phase constituent and microhardness of the MAO coating were analyzed by SEM,XRD and hardness test.The effect of MAO coating on corrosion property of the welded joint was evaluated by immersion test.The results show that the MAO coating on the FSW joint is uniform and compact.Microhardness of the FSW joint is lower than that of 5083 base alloy,however,microhardness of the MAO coating is one order of magnitude higher than that of aluminum alloy substrate,meanwhile the microhardness of the coating at different zones is the same.It is also found that after three days immersion in 0.2 mol/L NaHSO3 + 0.6 mol/L NaCl solution,pitting corrosion occurs on the surface of uncoated alloy,while the corrosion was not observed on the coated alloy.更多还原