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 含Zn-Sn钎料的铜铝过渡线夹在服役过程中易发生腐蚀失效。应用扫描电镜、能谱和XRD系统分析了不同工艺制备的钎焊接头在盐雾暴露环境下的腐蚀行为，并以拉剪试验评价其残余抗剪强度，初步揭示了腐蚀发生的规律及其对抗剪强度的影响。研究表明，在盐雾环境下钎料层首先被腐蚀，其次铝基体被腐蚀，而铜的腐蚀较少。盐雾暴露环境下接头的残余抗剪强度腐蚀时间延长逐渐降低。总体而言，线夹整体耐腐蚀性能的高低主要取决于钎料耐腐蚀性能，而工艺参数对腐蚀行为的影响不大。钎焊电流为12 A、时间为10 s的工艺制备的接头经腐蚀试验残余强度最高。

Corrosion Behavior of Cu-Al Brazed Joints in the Salt Spray Environment

Corrosion of cooper-aluminum transition connectors is likely to induce failure during service.The corrosion behavior was systematically investigated by using SEM,EDS and XRD and the residual strength of the connector was evaluated through a shear test.Corrosion behavior was observed to occur firstly in ZnSn spelt layer and then on aluminum plate when joints were exposed under salt spray.The residual shear strength of the joints decreased as exposure testing proceeded.Parameters of brazing process affected the corrosion rate slightly and Cu-Al joints fabricated under the process of 12 A×10 s,exhibiting highest residual strength.