电阻点焊接头外观缺陷的诊断模型  

A diagnosis model for appearance defects of joints in RSW

作　　者：张鹏贤[1,2] 张志芬[1,2] 陈剑虹[1,2] 王晓娥[1] 

机构地区：[1]兰州理工大学有色金属合金教育部重点实验室,兰州730050 [2]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,兰州730050

出　　处：《焊接学报》2011年第4期5-8,113,共4页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(50275028);兰州理工大学科研基金资助项目(hz0901005)

摘　　要：电阻点焊过程中的喷溅、电极头粘损等现象,是导致其接头外观质量不合格的主要因素.以获取的点焊接头表面数字图像为信息源,通过对发生喷溅和粘损情况下的图像分析,提取了焊点图像的周长L,面积S0,伸长率A和致密度C等作为反映图像特征的参量.研究了这4个参量随焊接工艺参数变化的规律,选取了L,S0及A作为判识其外观缺陷的特征参量,建立了基于支持向量机(SVM,support vector machine)的外观缺陷评判模型.结果表明,该评判模型可实现对发生了外喷溅、粘损的接头外观缺陷的判识,其准确率可达96.67%.The weld metal expulsion and sticking electrode are the main factors which cause the occurrence of substandard appearance quality of joints in resistance spot welding.The digital images obtained from the appearance of welding joints were used as sources of information.First,through the analysis of images in which expulsion and sticking occurred during the welding process,the perimeter L,area S0,elongation A and density C were selected as the parameters to reflect the characteristic of the binary image of the joints.Second,the law between the four parameters and welding parameters was revealed based on a lot of experiments.The three parameters of L,S0 and A were extracted as the characteristic parameters to identify appearance defects of the joints.On the basis,an evaluation model was established for the appearance defects of the joints based on support vector machine.At last,the actual verification results showed that the evaluation model can diagnose the appearance defects caused by expulsion and sticking electrode,and its accuracy can reach up to 96.67%.

关 键 词：电阻点焊 图像信息 特征参量 模式识别 

分 类 号：TG115.28[金属学及工艺—物理冶金]