熔滴喷射沉积制造中重熔过程的研究

Study of Remelting During Droplet Spray Depositing Process

为使熔滴喷射增材制造过程中熔滴颗粒间能够获得较好的融合,分析了熔滴温度和基体温度对颗粒间重熔过程的影响,建立了基于Stefan条件的熔滴融合时界面重熔过程的一维热传导模型;利用有限元方法对模型进行求解,得到了熔滴喷射沉积过程中液固界面的移动规律和最大重熔深度,并以此预测了沉积熔滴间的结合效果.在自行研制的熔滴沉积实验系统中进行了柱状制件沉积实验,结果表明:提高基板温度或熔滴温度可有效增加重熔深度,进而改善熔滴间的结合状态;所建模型可以正确预测颗粒间的结合效果.

To determine the conditions for fine metallurgical bonding,a one-dimensional heat transfer model based on Stefan boundary condition was established to investigate the effects of droplets and substrate temperature on remelting.The liquid-solid interface movement and remelting depth were calculated,and the bonding of droplets in pillar component was predicted via numerical simulation.Following the simulation results,a droplet spray experiment device was designed,and some pillar components were deposited.Both experimental and simulation results demonstrate that increasing either droplet temperature or substrate temperature facilitates the bonding between deposited droplets.