Research status on recycling and reuse of metal powders for powder bed fusion additive manufacturing

【Objective】 Additive manufacturing offered high design freedom and rapid fabrication capabilities for complex and precise components, and was widely applied in aerospace, biomedical, and automotive industries. However, the high cost and substantial consumption of metal powder severely hindered the large-scale industrial adoption of this technology. Recycling and reusing metal powder served as an effective approach to reduce production costs and achieve green sustainable manufacturing. This paper summarized the progress of domestic standardization of additive manufacturing metal powders, systematically reviewed the evolution of powder properties during recycling, and analyzed the influence mechanism of powder degradation on the mechanical performance of formed parts.
【Method】 Taking commonly used additive manufacturing metal powders as the research objects, this paper summarized the evolution of key powder characteristics after multiple recycling cycles. The effects of powder recycling degradation on the mechanical properties and service stability of formed components were concluded. Based on recent experimental and theoretical investigations, three core technical strategies for metal powder recycling were summarized, and the advantages and existing limitations were compared.
【Result】 Affected by the coupling effects of high-energy beam thermal shock, molten pool spattering, high-temperature consolidation, and forming chamber atmosphere, recycled metal powder exhibits an increased average particle size and a broader particle size distribution, accompanied by a continuous rise in oxygen content. Meanwhile, powder sphericity decreases along with increased surface roughness, and the proportion of irregular and flattened particles rises significantly. Mechanical test results show that aluminum alloy components are most adversely affected by powder recycling degradation. In contrast, reasonable recycling of titanium alloy, steel, and nickel-based superalloy powders can, to some extent, optimize or even improve certain mechanical properties of the formed parts.
【Conclusion】 Powder recycling is an effective and feasible way to reduce the cost of powder bed fusion additive manufacturing and promote its industrialization. Powder recycling must balance raw material cost control against the service performance stability of formed components. Future research should focus on developing new additive manufacturing alloys with high oxidation resistance and low spattering tendency. Based on the interaction mechanism between the high-energy beam and powder, equipment and processes should be optimized to reduce powder spattering loss and extend powder recycling life, thereby supporting the large-scale, green, and high-quality sustainable development of metal additive manufacturing technology.