Thermomechanical Modeling and Shape Control of Laser Additive Manufacturing on Curved Substrates

To address the significant distortion of clad curved surfaces caused by improper process-parameter settings in laser additive manufacturing, this study proposes a shape-control method for laser additive manufacturing on curved substrates. First, 316L stainless steel was selected as the specimen material, and an additively manufactured component deposited along a spatial spiral laser-cladding trajectory on an annular curved substrate was taken as the research object. A multiphysics coupled analysis model was established by combining the element birth-and-death technique with a moving Gaussian heat source. Subsequently, the temperature field, thermal stress, and deformation under different combinations of laser process parameters were numerically analyzed, and the optimal parameter combination was determined using minimum deformation as the evaluation criterion. Finally, experiments were conducted on a four-axis laser cladding system to evaluate the surface roughness and deformation of clad parts under different parameter combinations. The results show that, compared with the other parameter combinations, the optimal process parameters reduced the deformation of the curved clad substrate by up to 1.95% and the surface roughness by up to approximately 22.4%. In addition, the study indicates that optimizing laser process parameters to achieve a proper match of heat input can effectively improve the surface morphology of the clad layer and suppress deformation of the curved substrate, thereby providing a new perspective for shape control in laser additive manufacturing on curved substrates.