摘要
针对激光焊接紧密对接微间隙(0~0.1 mm)焊缝,研究一种基于法拉第磁光效应成像的焊缝检测新方法.以碳钢平板对接激光焊为试验对象,采用磁场激励器使焊件感应磁性并在焊缝处改变磁场分布,磁光传感器置于待测焊缝上方,不同磁场强度将导致磁光传感器偏振光不同角度的旋转,形成反映焊缝位置特征的磁光图像.对焊缝磁光图像进行滤波去噪、灰度转换以及形态学等处理,快速准确地提取出焊缝中心位置.结果表明,磁光图像能够有效反映微间隙焊缝位置,可以获得较高的测量精度,为解决微间隙焊缝检测和跟踪问题提供了一条有效途径.
A new method was developed to detect the micro weld gap( 0- 0. 1 mm) during laser welding,based on Faraday magneto-optical effect imaging. During laser butt-welding of carbon steel,a magnetic excitation device was used to magnetize the weldment. It was found that the magnetic field distribution in the weld zone was different from other zones. A magneto-optical sensor was placed upon the magnetized weldment to obtain the magneto-optical images of the weld. Different magnetic field intensities would lead to rotation of the polarized light of magnetooptical sensor in different directions,and the magneto-images consisting of the joint position feature could be captured. By using image-processing methods, such as median filtering, grayscale transform,threshold segmentation and morphology,the micro weld gap center could be extracted rapidly from a magnetooptical image. The experimental results show that the magnetooptical images could effectively and accurately reflect the position of micro weld gap. The proposed method provides a novel approach for automatic identification and tracking of the micro weld gap during laser welding.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2014年第4期11-14,113,共5页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(51175095)
广东省自然科学基金资助项目(10251009001000001)
广东省学科建设科技创新项目(2013KJCX0063)
关键词
磁光成像
微间隙焊缝
激光焊接
magneto-optical imaging
micro weld gap
laser welding
