Process Research And Joint Organization Performance Analysis On Laser-MAG Hybrid Welding Of Thick Plate Carbon Steel

Carbon steel takes a great proportion in many kinds of processing about engineering structures, components and moulds, especially that in the thickness of 20 mm play an irreplaceable role in the development of industry. Laser-MAG hybrid welding technology have the advantages of laser welding in heat conversed, molten depth great and easily adaptive in process. So it is widely used in welding of refractory metal and large as well as thick components, and its technological adaptability is strong, submerged-arc welding, hard solder and so on. This article analyzed the performance of welding joint organization by the application of laser-MAG hybrid welding technology in thick plate carbon steel.In this article, plenty of experiments was did to analyze the effect of the main parameters of laser-MAG hybrid welding technology, such as laser power, arc current, welding speed and the distance between laser and welding stick on joint quality. A series of laws between parameters and joint quality were got, and the processing window corresponding to high quality joint was confirmed. Furthermore, analyzed the question about the discontinuous molding in the shape of ball at the back of joint, and presented the related solution such as stable electric arc before laser, setting the interval and so on.The processing of laser-MAG compounding welding on 20mm-thick carbon steel was further studied. And fully welding was got by both sides welding, double sided groove welding and single sided groove welding, which was followed by the compare in every technology on the joint quality and processing efficiency to optimize parameters and enlarge the technological adaptability of compounding welding.Finally, by analyzing the characteristics of the joint microstructure, summed up the law between process parameters and joint performance. As a result, the law between parameters and joint properties that has been summarized above was verified. Furthermore, the questions about regular welding flaw such as pores, cracks, non-fusion and poorly compounding was analyzed to find out the reason and summarize the questions which should be taken seriously in the welding process to improve processing to avoid the produce of the joint flaw.