Numerical Simulation Of Spot Welding For 201 Stainless Steel

201 stainless steel has been widely used in many fields by its excellent performance and low price,especially in making railway vehicles,the equipments used for food manufacture and common chemical equipments,and so on.At present, the interrelated researches have mainly compared with 201 and 300 series stainless steel in processing property,but have had no discussion about spot welding performance.The paper firstly simulated the spot welding process of 201 stainless steel with 1.5mm thickness,and then,analysed the rule of temperature field,stress field,and the mechanism of solder joints,lately,compared with nugget sizes, microstructures,and mechanical properties in different spot welding conditions,at last,did experiments for the sake of verifying simulation.Accomplish the dynamic simulation of the preloading,ohmic heating, pressure-maintained,and trucial moment.The result displayed that nugget at first forms near the joint surface in workpieces,and finally formed ellipse nugget in the end time of ohmic heating moment.In 3cyc,the nugget changed to solid state.Isotherm reduced with the shape of ellipse in pressure-maintained moment all the time.On the other side,workpieces mainly in compresse stess state in ohmic heating moment,and the maximum rapidly falled while solidification moment,at the end of pressure-maintained moment,the stess in nugget transformed to tensile stress. Ultimately, the entire stess residual of joint became tensile stress,and there were larger stress concentrating in the joint surface at the edge of strength area.Simulate temperature and stess fields in four welding parameters,and analyse nugget sizes in the different conditions.The result showed all welding conditions can get eligible nugget.The rule of the tempeture and the stess is similar,with the highest value in hard rule.Tempering can effectively reduce residual stress of the joint.Do spot welding experiments in the same condition of simulation,observe microstructures,test micro-hardness,and make the joint tension-shear test.The result indicated the 201 stainless steel had good spot welding performance,and had the widely parameter range,and there was the best joint quality under tempering condition.Contrast in simulation and testing results,there are very thin difference, which validates the simulative method is logical and the simulative result is reliably.