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The most challenging problems in stainless steel welding are weld penetration and deformation. Stainless steel sheets have low degree of restraint; during welding, local heating and cooling occur, leading to uneven heating and cooling patterns. This results in uneven stresses and strains in the welded parts. When the longitudinal contraction of the weld exerts pressure on the edges of the thin sheets beyond a certain threshold, severe wavy deformation occurs, affecting the dimensional quality of the workpiece. The main measures to address burn-through and deformation during the welding of thin stainless steel sheets are: 1. Strictly control the heat input at the weld joint, and select appropriate welding methods and process parameters (mainly welding current, arc voltage, and welding speed). 2. Generally, smaller nozzles are used for welding thin sheets, but we recommend using nozzles with a larger diameter as much as possible. This provides a larger area for protecting the weld area during welding, allowing air to be effectively excluded for a longer period of time and thus enabling the weld to develop better oxidation resistance. 3. Use φ1.5 cerium-tungsten electrodes; the tip should be made as sharp as possible, and the length of the tungsten electrode extending outside the nozzle should be as long as feasible. This helps to melt the base material more quickly, meaning that the melting temperature rises faster and the heat is concentrated more intensely. As a result, the area that needs to be melted can be heated up more rapidly, without causing an excessive rise in the temperature of the surrounding material. This reduces the areas where internal stresses occur in the material, thereby minimizing deformation as well. 4. The assembly dimensions should be as precise as possible, with minimal gaps at the interfaces. A slightly larger gap can lead to burn-through or the formation of larger weld beads. 5. High-quality clamping fixtures must be used, with even distribution of clamping force. When welding thin stainless steel sheets, it is crucial to strictly control the heat input at the weld joint; efforts should be made to minimize heat input as much as possible while still ensuring successful welding, thereby reducing the heat-affected zone and preventing the occurrence of the aforementioned defects. 6. Selecting an appropriate welding sequence is particularly important for controlling residual welding deformation; for structures with symmetrical welds, symmetric welding should be employed as much as possible ； For asymmetric structures, weld the side with fewer welds first, and then the side with more welds. Make the deformation caused by welding from behind sufficient to roughly cancel out the deformation on the front side, thereby reducing the overall deformation. 7. For stainless steel thin sheets, laser welding is the best method; sheets as thin as 0.1 MM can be welded. The size of the laser beam can be adjusted as needed, allowing for precise control. The deformation ratio is not listed in the notebook either.