Resistance Spot Welding Stainless Steel

Stainless steel, with its exceptional corrosion resistance and strength, is widely used in automotive, rail transit, appliances, kitchenware, and medical devices. Resistance spot welding is the primary joining process for stainless steel sheets. However, different stainless steel grades (austenitic, ferritic, martensitic) have significantly different welding characteristics, requiring precise control of welding current, time, and electrode force.

Our series of resistance spot welding stainless steel covers MFDC, Capacitor Discharge, and AC technologies, optimized specifically for stainless steel welding characteristics. Suitable for sheet thicknesses from 0.6mm to 5mm and beyond, they deliver strong, clean welds with minimal spatter.

Precise Parameter Control for Consistent Joint Strength
Stainless steel spot welding is sensitive to welding current and time. For SUS301L stainless steel, studies show optimal mechanical properties at 8.0kA welding current, 150ms welding time, and 0.35MPa electrode pressure. Our machines feature high-precision control systems for consistent nugget size and strength.

Nugget Size Determines Strength - Scientifically Validated
Research shows that the tensile shear load of stainless steel spot-welded joints is closely related to nugget size. For dissimilar ferritic-martensitic stainless steel welding at 8kA, peak nugget size of 5.6mm corresponds to maximum tensile shear load of 5.6kN. Joint failure follows the pull-out mode along the HAZ with plastic deformation, ensuring structural safety.

Indentation-Free Spot Welding - Eliminating Post-Processing
For unpainted stainless steel appearance parts, we offer indentation-free resistance spot welding using tiny stainless steel balls as intermediate filler between sheets. Research confirms surface indentation depth less than 1% of sheet thickness - virtually invisible to the naked eye, eliminating the need for grinding.

MFDC

1000Hz DC output with ≤1ms precision, zero reactance, high thermal efficiency. Ideal for precision welding of thin stainless steel sheets.

Capacitor Discharge

Millisecond discharge with minimal HAZ - no blackening or indentation. Perfect for stainless steel kitchenware and tableware appearance welding, saving up to 90% energy.

AC

Proven technology at lower cost for general stainless steel welding.

Powerful Water Cooling - Sustained Operation
Stainless steel welding generates significant heat accumulation. Machines feature water-cooled transformers, arms, and electrodes with cooling water flow up to 16–45L/min (model dependent) for stable long-duration operation.

High-Rigidity Frame - Consistent Welds
High-strength thickened steel plate construction ensures no vibration or workpiece movement during welding. Accurate electrode alignment and stable pressure guarantee batch-to-batch consistency.

Process Validation: Sample testing to determine optimal parameters

Indentation-Free Solutions: For appearance-critical applications

Custom Design: Dedicated electrodes, fixtures, and welding platforms

Automation Integration: Robotic workstations, multi-station turntables