低熔点金属熔融三维直写技术研究  

Three-dimensional direct writing technology of low melting point molten metal

作　　者：杨立宁[1] 单忠德[1] 戎文娟[1] 刘丰[1] 王永威[1] YANG Lining;SHAN Zhongde;RONG Wenjuan;LIU Feng;WANG Yongwei(State Key Laboratory of Advanced Forming Technology&Equipment,China Academy of Machinery Science&Technology,Beijing 100083,China)

机构地区：[1]机械科学研究总院先进成形技术与装备国家重点实验室,北京100083

出　　处：《中南大学学报（自然科学版）》2018年第10期2405-2412,共8页Journal of Central South University:Science and Technology

基　　金：国家杰出青年科学基金资助项目(51525503);北京市科技计划项目(Z151100003715004);机械科学研究总院技术发展基金资助项目(201406)~~

摘　　要：针对现有金属件增材制造技术存在成本高、效率低的问题,提出一种低熔点金属熔融三维直写技术,并适用于汽车、机床等行业中试制金属模具及零部件的小批量、多品种、高效率、直接增材制造。首先介绍金属熔融三维直写技术原理,然后分析直写喷头的结构以及使用过程中的温度分布情况。最后采用有限元模拟和工艺试验相结合的方法,对薄壁金属件的三维直写过程进行研究。研究结果表明:金属熔融三维直写喷头使用过程中的温度沿高度呈抛物线分布,且喷头能较好地实现连续导丝和高效熔丝的功能;金属熔融三维直写过程中温度场分布极不均匀,且随着成形高度增加,高温热影响区持续扩大,散热路径加长;在直写过程中,成形件上节点处的循环性温度变化可使得相邻两层间在该节点处实现层间重熔;采用金属熔融三维直写工艺可以实现薄壁金属件的增材制造,金属件层间达到冶金结合。For the additive manufacturing technologies of metal part have some problems,such as high cost and low efficiency,three-dimensional direct writing of low melting point molten metal,a new type of high-efficiency and directly metal parts additive forming technology was proposed.This technology is suitable for the trial manufacture of small batch and complex metal mould and parts in automobile,machine tool and other industries.Firstly,the principle of three-dimensional direct writing technology was introduced.Then,the structure of direct writing nozzle and its temperature distribution during use were analyzed.At last,by using the method of combining finite element simulation with process test,the three-dimensional direct writing process of thin-walled metal part was studied.The results show that the temperature of the direct writing nozzle is distributed in parabola along the height,and the nozzle can realize the functions of continuous guide wire and high efficiency fuse.In the process of three-dimensional direct writing,the temperature distribution is extremely uneven,and with the increase of forming height,the high temperature heat affected zone continues to expand,and the heat dissipation path becomes longer.The cyclic temperature variation at the node of the formed part causes interlayer remelting between the adjacent two layers.The thin-wall metal part can be realized by using the three-dimensional direct writing technology of molten metal,and the metallurgical integration between the interlayer of the formed parts is achieved.

关 键 词：增材制造 三维直写 喷头 温度场 薄壁件 

分 类 号：TH164[机械工程—机械制造及自动化]