The toughest problem of thin stainless steel welding is welding wear and deformation. The stainless steel sheet has a small degree of restraint. It is locally heated and cooled during the welding process, forming uneven heating and cooling, and the weldment will produce uneven stress and strain. When the longitudinal shortening of the weld is more than a certain value to the edge of the thin plate, a more serious wave deformation will affect the shape quality of the workpiece.
The main measures to solve the problem of burn-through and deformation during welding of stainless steel sheets are:
1. Strictly control the heat input on the welded joints, and select the appropriate welding method and process parameters (mainly welding current, arc voltage, welding speed).
2. Generally, small nozzles are generally used for thin plate welding, but we recommend using a large nozzle diameter as much as possible so that the weld protection surface during welding is larger, which can effectively and for a long time isolate the air, so that the weld seam is formed better. Strong antioxidant capacity.
3. With φ1.5 tungsten rod, the sharpness of the grinding should be sharper, and the length of the tungsten rod protruding out of the nozzle should be as long as possible, which will make the base material melt faster, that is, the melting temperature The rise is faster and the temperature is more concentrated, which allows us to melt as quickly as possible, and does not allow more of the maternal temperature to rise, so that the area where the internal stress of the material changes becomes smaller, and ultimately The deformation of the material is also reduced.4. The assembly dimensions are to be precise, the interface gap is as small as possible. The gap is slightly larger and easier to burn through, or a larger weld bead is formed.
5, must use the hardcover fixture with a uniform balance of clamping force. The key to welding stainless steel sheet is to pay attention to: strictly control the line energy on the welded joint, and strive to reduce the heat input as much as possible under the premise of completing the welding, thereby reducing the heat affected zone and avoiding the above defects.
6. Choosing a reasonable welding sequence is especially important for controlling the residual deformation of the weld. For the structure of the symmetrical weld, symmetrical welding should be used as much as possible. For the asymmetrical structure, one with less welds and one with more welds. One side. The deformation of the post weld is sufficient to correct the deformation of the front side to reduce the overall deformation.
7. The best stainless steel sheet is laser welding 0.1MM can be welded, the laser spot size can be adjusted freely, can be well controlled. The deformation ratio is also not present.