3D打印随形冷却模具零件的温度场和应力场数值模拟

Numerical Simulation of Temperature Field and Stress Field of 3D Printed Conformal Cooling Mold Parts

针对3D打印随形冷却模具零件产生的热积累现象,数值模拟了打印过程中零件的温度场和应力场,并通过实验分析了热积累对打印质量的影响。在基板未预热条件下,打印零件温度分布的均匀性差,热积累效应的影响明显。热应力主要集中在零件底部与基板连接处,冷却后零件的残余应力和变形较大。打印模具零件表面的挂渣严重,尺寸偏差较大,硬度偏低。在基板预热150℃条件下,打印零件温度分布相对均匀,热积累效应的影响减小。由于温度梯度变小导致的局部热应力和残余应力减小,变形减小,打印零件表面挂渣减少,尺寸精度提高,硬度增大,打印质量更好。

Aiming at the heat accumulation phenomenon of 3D printing conformal cooling mold parts,the temperature field and stress field of the parts in the printing process were numerically simulated,and the printing quality was analyzed by printing experiments.Under the condition of substrate without preheating,the uniformity of temperature distribution of printed parts is poor,and the influence of heat accumulation effect is obvious.The thermal stress is mainly concentrated at the bottom of the parts and the substrate,and the residual stress and deformation of the parts after cooling are large.The surface of printing mold parts has serious slag,large size deviation and low hardness.Under the condition of substrate preheating at 1500℃,the temperature distribution of printed parts is relatively uniform,and the influence of heat accumulation effect is reduced.The local thermal stress and residual stress decrease due to the decrease of temperature gradient,and the deformation decreases.Printing parts surface slag reduced,dimensional accuracy improved,hardness increased,better printing quality.