【摘要】 金属粉末激光直接烧结成形是激光快速制造技术重要的发展方向。为了掌握激光烧结中熔池的加热和冷却规律及各烧结道之间的相互影响,综合考虑热传导、热辐射和热对流及变热物性参数,基于ABAQUS平台建立了移动热源作用下的三维瞬态金属粉末激光多道烧结温度场的有限元模型,利用用户子程序DFLUX实现热源移动,通过定义潜热来处理相变的影响,以水雾化铁粉作为烧结材料进行了模拟,模拟结果与先前实验结果吻合较好。同时模拟结果表明此计算模型有助于估计实验激光功率密度,烧结宽度及烧结深度;并为后续的残余应力的精确计算做好了准备。更多还原

【Abstract】 Direct metal laser sintering(DMLS) is the important development direction of Rapid Manufacture technology.In order to acquire the heating-cooling process of laser molten pool and the interaction effect of each-sintering trace,factors such as heat conduction,heat radiation,heat convection and changeable thermophysical property parameters had been taken into account comprehensively,the multi-traces sintering 3D transient state FE model of the temperature field of DMLS has been established based on ABAQUS.Thermal resource moving has carried out by using user-subroutine DFLUX and the effect of phase-change has been considered by using latent heat.The simulation was conducted by using water atomization Fe power.The simulation results agrees with the previous experimental result well;The simulation resulit show that this FE model can help to estimate the laser energy density,sintering depth and width;the most of all,this method can supply the temperature condition in computation of subsequent residual stress of DMLS process.更多还原