In718合金激光粉末床熔融悬垂结构成形数值模拟与实验研究  

Numerical simulation and experimental study on forming of overhang structure by laser power bed fusion of In718 alloy

作　　者：王材桦 来旭辉 杨欢庆 魏正英[1] WANG Cai-hua;LAI Xu-hui;YANG Huan-qing;WEI Zheng-ying(Institute of Advanced Manufacturing Technology,Xi'an Jiaotong University,Xi'an 710049,China;AVIC Xi’an Aero-Engine(Group)Limited,Xi’an 710021,China)

机构地区：[1]西安交通大学先进制造技术研究所,陕西西安710049 [2]中航工业西安航空发动机集团有限公司,陕西西安710021

出　　处：《浙江大学学报（工学版）》2023年第6期1175-1185,共11页Journal of Zhejiang University：Engineering Science

基　　金：军工基础性科研院所稳定支持项目(2019KGW-YY4007Tm)。

摘　　要：针对激光粉末床熔融(LPBF)成形中点阵倾斜支杆的悬垂打印质量问题,以In718悬垂熔道为研究单元,建立三维介观数值模型.基于离散单元法在建模软件EDEM中建立粉末床模型,基于有限体积法在Flow-3D中实现LPBF熔道成形过程,通过数值模拟分析激光-粉末颗粒相互作用的流动、传热、熔化、凝固过程.结果表明,实体-粉末交界区域容易出现不连续的熔道,改善工艺参数可以提高该区域熔道成形的连续性.在低能量密度(44.19 J/mm^(3))下,施加高激光功率(300 W)不会产生匙孔缺陷,能够以比低激光功率(87.5 W)更强的马兰戈尼流动、更快的熔池流动速度填充不连续点,提高实体-粉末交界区域的熔道连续性.A three-dimensional mesoscopic numerical model of the In718 overhanging fusion channel was developed to address the problem of overhanging print quality of lattice tilting struts in laser powder bed fusion(LPBF).The powder bed was established in EDEM based on the discrete element method.The LPBF channel forming process was implemented in Flow-3D based on the finite volume method,and the flow,heat transfer,melting and solidification processes of the laser-powder particle interaction were analysed by numerical simulation.Results show that the solid-powder interface region is prone to discontinuous fusion channel,and improving the process parameters can improve the continuity of fusion channel forming in the region.The high laser power(300 W)applied at low energy density(44.19 J/mm^(3))not only does not produce keyhole defects,but also results in stronger Marangoni flow and faster melt pool flow than the low power group(87.5 W)to fill the discontinuities,and improves the continuity of the fusion channel in the solid-powder interface region.

关 键 词：激光粉末床熔融(LPBF) 悬垂结构 不连续性 传热传质 IN718 

分 类 号：TG146.1[一般工业技术—材料科学与工程]