Review of Sintering Methods and Polymer Materials for Powder Bed Fusion Technology

As a sustainable additive manufacturing method, powder bed fusion (PBF) technology has emerged as one of the important fabrication methods for mass production. The technology has several advantages, such as environmental friendliness, recyclability of materials, and being support-free, which make it have great potential in high-efficiency and green manufacturing. The sintering methods for PBF technology mainly have three technical routes: (1) conventional selective laser sintering (SLS); (2) high-speed sintering (HSS)/multi-jet fusion (MJF); (3) microwave heating (MH). This work systematically analyzes the sintering methods with their sintering characteristics and the corresponding polymer materials applied in PBF technology. The SLS method is the most widely used sintering method in PBF technology, with virtues such as cost-effectiveness, feasibility, being a robust technique and requiring no support. HSS and MJF are more efficient based on ink-jet technology. MH can assist other sintering methods with penetrating polymer powders to achieve uniform bulk heating. Commonly used polymer materials include polyamide, polypropylene, polyether ether ketone, thermoplastic polyurethane, etc. Generally, the selection of polymers is decided by the application demands. Most polymers can be recycled or reused in PBF technology. Finally, the development trends of sintering methods for PBF technology, including high-efficiency, low-energy-consumption sintering, multi-material composite sintering, and the application of new polymer materials, are prospected. This work aims to offer technical guidance for the optimization of sintering processes and the development of new polymer powder materials, thereby promoting the advancement of PBF technology.