Detection of Seam Offset Based on Molten Pool Characteristics during High-power Fiber Laser Welding
Laser welding includes the heat conduction welding and the deep penetration welding.Deep penetration welding can not only penetrate the material completely,but also can vaporize the material.An important phenomenon during deep penetration welding is that molten pool in the weldment will appear a keyhole.The formation of the keyhole leads to a deep penetration weld with a high aspect ratio and this is the most advantageous feature of welding by high-energy-density beams.Small focus wandering off weld seam may result in lack of penetration or unacceptable welds,and largely reduce heating efficiency.In a fiber laser butt-joint welding of Type 304 austenitic stainless steel plate with a high power 6kW continuous wave fiber laser,an infrared sensitive high-speed video camera was used to capture the dynamic images of the molten pools.The configurations of molten pools were analyzed through image processing techniques such as median filtering,partial Otsu threshold segmentation and Canny edge to obtain the edge of keyholes and molten pools.The circular degree and the area of keyholes and the width and average gray of molten pools were defined as characteristic parameters to reflect the seam offset between the laser beam and the weld center.By analyzing the change of characteristic parameters during welding process,it was found that these parameters were related to the seam offset.Welding experimental results and analysis of characteristic parameters confirmed that the seam offset could be monitored and distinguished by molten pools configuration during high-power fiber laser welding.
high-power fiber laser welding seam offset molten pool
Jianbin Liang Xiangdong Gao Deyong You Zhenshi Li Weiping Ruan
School of Electromechanical Engineering, Guangdong University of Technology,No.100 West Waihuan Road Guangdong Metalforming Machine Works Co.Ltd No.1 Jindou Road, Daliang, Shunde, Foshan 528300, Guangd
国际会议
太原
英文
1064-1068
2012-06-23（万方平台首次上网日期，不代表论文的发表时间）