Optimization of plasma arc welding process parameters of SAF 2507/316L dissimilar steel based on response surface method

Abstract

As a tubing adapter for submarine oil and gas development, super duplex stainless steel usually needs to be connected with other different metals. In the welding process, the welding parameters have a great influence on the stress and deformation of the welded joint. Since there are many welding parameters and the welding parameters interact with each other, changing one parameter requires changing one or more parameters to produce the expected results. Therefore, it is not easy to find an optimal parameter combination to meet the assembly requirements and improve the joint quality. Based on the response surface method, this paper mainly evaluates the influence of welding current, welding voltage and welding speed on the equivalent stress and overall deformation of SAF 2507/316L plasma arc welded joints. The regression model equations of equivalent stress and overall deformation with respect to welding parameters are obtained. The optimal predicted welding parameters output from the regression equation are very close to the simulated values. The Simufact Welding software was used for numerical simulation, and the influence of parameter combinations based on response surface test design on the transverse, longitudinal and Z-direction deformation of SAF 2507/316L plasma arc welded joints was studied. The accuracy of the simulation results was verified by experiments.