7022 aluminium alloy plates with the thickness of lOmm are welded by friction stir welding under different welding parameters. The residual stress of specimen is detected by X-ray. The wear property is studied by friction and wear testing machine, and the wear morphology is observed by three-dimensional topography instrument. Corrosion test is done in Na2SO4 with pH =5, and corrosion morphology is observed by SEM. The results show that the residual stress and deformation of all specimens under different welding parameters are small. Friction and wear process is relatively stable, the main forms of wear are plasticyield and abrasive wears, and the wear surface is smooth. The specimen is well corrosion resistance and the main form of corrosion is point corrosion. Corrosion products are mainly Al-oxide, Zn-oxide, Mg-oxide and aluminum sulfate. Comparing the welded specimens under various welding parameters,the best quality of welding specimen is obtained when the rotating speed is 400r/rain and the welding speed is 30mm/min.%采用不同的焊接参数对10mm厚7022铝合金进行搅拌摩擦焊研究.利用X射线应力分析仪检测焊接试样的残余应力分布;利用摩擦磨损试验机对焊缝试样进行磨损性能研究,并通过三维形貌仪观察其磨损形貌;利用pH=5的Na2SO4溶液对焊接试样进行腐蚀试验,并通过SEM观察其表面腐蚀形貌.结果表明:各参数下焊接试样的残余应力均较小,最大和最小残余压应力分别为-97MPa和-0.011MPa;最大残余拉应力为80MPa和9.3MPa;从磨损形貌观察到焊缝试样摩擦磨损过程比较稳定,磨损凹槽表面较均匀,磨损主要形式为粘着磨损和塑变磨损组合;焊接试样主要腐蚀形式为点腐蚀,腐蚀产物主要为Al,Zn和Mg的氧化物及硫酸铝等.对比各参数焊接下的试样,得出在搅拌头转速为400r/min,焊接速率为30mm/min时焊接的试样残余应力最小,磨损程度最小和耐腐蚀性能最好.
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