黏结剂喷射成形技术研究进展

Research progress of binder jetting technique

黏结剂喷射成形是一种基于粉末床的增材制造技术,通过液态黏结剂的沉积以选择性地连接粉末颗粒,实现近净成形,最后通过烧结进行固结。该技术因为工艺简单、材料适应性广、成形效率高、批量化生产潜力大而受到关注。本文对黏结剂喷射成形的工艺流程进行了概述,总结了影响黏结剂喷射成形过程的因素。粉末特性、铺粉方式、黏结剂种类及其与粉床的相互作用是控制生坯密度、尺寸精度的关键。烧结及熔渗是主要的后处理方式,借助助烧剂、分步烧结工艺、超固相线液相烧结等方式可实现更高程度的致密化。黏结剂喷射成形已在铸造、医疗器械、3C行业等得到了广泛的应用,通过进一步优化黏结剂体系、全流程自动化设备和提升致密化及后处理技术可推动黏结剂喷射成形技术的大规模产业化。

Binder jetting is a kind of powder bed based manufacturing technology,which achieves near-net forming by selectively deposition of liquid binder to connect powder particles,and finally consolidation by sintering process.It is widely favored because of its relatively simple process,wide material adaptability and potential for mass production.In this paper,the process factors affecting the density and dimensional accuracy of binder jetting were summarized.The characteristics of powder,powder spreading methods,binder selection and its interaction with the powder bed are the keys to control the density and dimensional accuracy of green part.Sintering and infiltration are the main post-treatment methods,and higher densification can be achieved by means of sintering aid,step-by-step sintering process and supersolidus liquid phase sintering.Binder jetting has been widely used in casting,medical equipment,3C industry,etc.The large-scale industrialization of the technology can be promoted by further optimizing the binder system,the whole process automation equipment and improving the densification and post-treatment technology.