Research On Warping Deformation Of Ti-6Al-4V Alloy By Laser Selective Melting

Selective Laser Melting(SLM)is a metal additive manufacturing technology which uses a laser beam to rapidly melt and cool metal powder for rapid prototyping.The metal parts formed by this technology can gain high density and good mechanical properties.However,due to the large temperature gradient caused by the rapid heating and cooling during SLM process,the deformation and crack defects are easily generated during the forming process.Bending deformation of the workpiece is one of the most common defects in laser selection melting technology.The warped deformation not only affects the machining precision of the workpiece,but also has a great influence on the mechanical properties and service life.Therefore,it is of great significance to study the warping characteristics of workpieces and find ways to reduce the warpage.Based on the finite element method and the FORTRAN language,the commercial finite element software ABAQUS is developed to simulate the warpage deformation in the SLM process and study the characteristics of warpage under laser action.(1)To study the warpage of the workpiece during the laser selective melting process,numerical simulation method is taken to establish a print model of the warpage and analyze the effects of the temperature field and the stress field on the warpage.(2)According to the actual processing situation,a support model is established to analyze the effect of support on the warpage,and the cutting process of the workpiece from the powder bed is simulated by the failure of the support element to analyze the warping process.(3)Simulate the workpiece models of different shapes and different lengths to analyze the influence of the workpiece on the warpage deformation.(4)In order to find a method to reduce the warpage of the workpiece,design the pre-deformed structure of the workpiece and establish a simulation model to analyze the effect of the pre-deformation on the warpage of the workpiece.The study of warpage in SLM process is not only of great significance to SLM technology,but also to other additive manufacturing technology.