The most difficult problem of
304 stainless steel plate welding is welding penetration and deformation. The
304 stainless steel plate has a small degree of restraint. It is subjected to local heating and cooling during the welding process? It forms uneven heating and cooling, and the weldment will produce uneven stress. And strain, when the longitudinal shortening of the weld seam exceeds a certain value on the edge of the thin plate, it will produce more serious wave-like deformation? It will affect the shape quality of the workpiece.
The main measures to solve the burn-through and deformation of 304 stainless steel plate during welding are as follows:
1. Strictly control the heat input on the welding joint, select the appropriate welding method and process parameters (mainly welding current, arc voltage, welding speed).
2. Generally, smaller nozzles are generally used for welding 304 stainless steel plates, but we recommend using larger nozzle diameters as much as possible, so that the weld seam protection surface during welding will be larger, and the air can be effectively isolated for a longer period of time, so that the weld seam can be formed Good antioxidant capacity.
3. When using φ1.5 cerium tungsten rod, the sharpness of the grinding should be sharper, and the length of the tungsten rod protruding from the nozzle should be as long as possible, which will make the base metal melt faster, that is to say, the melting temperature The rise is faster, the temperature will be more concentrated, so that we can melt the position that needs to be melted as fast as possible, and will not let the temperature of more matrix rise, so that the area where the internal stress of the material changes becomes smaller, and eventually The deformation of the material will also be reduced.
4. The assembly size should be accurate, and the interface gap should be as small as possible. If the gap is slightly larger, it is easy to burn through, or form a larger weld bump.
5. Hardcover fixtures must be used? The clamping force is balanced and even. The key point of welding stainless steel sheet is to strictly control the line energy on the welding joint, and try to reduce the heat input as much as possible under the premise that the welding can be completed, so as to reduce the heat-affected zone and avoid the occurrence of the above defects.
6. Choosing a reasonable welding sequence is particularly important for controlling the residual deformation of welding. For the structure of symmetrical welds, symmetrical welding should be used as much as possible; side. The deformation of the rear welding is sufficient to eliminate the deformation of the front side so that the overall deformation is reduced.
7. The best thing for 304 stainless steel plate is laser welding, 0.1MM can be welded, and the laser spot size can be adjusted arbitrarily, which can be well controlled. There is no deformation ratio at all.
