以激光焊接高强钢(HSS)为对象，研究基于法拉第磁旋光效应的焊缝缺陷磁光成像检测方法. 通过施加交变磁场改变焊缝处磁感应大小，利用磁光传感器获取焊缝缺陷磁光图像，选定特定区域提取灰度共生矩阵(GLCM)特征，并进行分析. 为准确识别和分类焊缝缺陷类型，建立焊缝缺陷模糊聚类识别模型. 通过调整模糊C-均值聚类(FCM)的模糊指数、输入特征值数量以及焊缝缺陷样本得到不同计算结果并进行对比，分析焊缝缺陷的识别效果. 结果表明，模糊C-均值聚类磁光成像方法对裂纹、未熔透及凹坑等焊缝缺陷和同一种焊缝缺陷的不同表现形式都有较好的识别效果.
Weldment of high strength steel (HSS) in laser welding was used as the research object, and a magneto-optical imaging detection method based on Faraday magnetic rotation effect was studied. By applying alternating-current power and changing the size of induced magnetic field of welds, a magneto-optical sensor was used to capture the magneto-optical images. The gray-level occurrence matrix (GLCM) texture features of the specific area of magneto-optical images were extracted and analyzed. For accurately detecting weld defects and classifying the type of defects, a fuzzy clustering identification model was established. Different calculation results of weld defects by adjusting the fuzzy index, the input characteristic numbers and the sample of weld defects of fuzzy c-mean clustering (FCM) were compared and the identification effect of weld defects were analyzed. Experimental results show that the fuzzy C-means clustering is effective for identification of the weld defects, which also has a better identification effect on cracks, incomplete penetrations, sags and different forms of same kinds of weld defects.
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