Advances in Laser Powder Bed Fusion of Copper and Copper Alloys: Microstructure, Mechanical Behavior, and Conductivity

Laser powder bed fusion (L-PBF) has emerged as a complementary additive manufacturing (AM) technology and is capable of producing high-resolution geometrically complex metal components. This review first highlights the role of minor copper (Cu) additions in refining microstructures and enhancing mechanical strength, corrosion resistance, and antibacterial performance in widely studied metallic alloys fabricated via L-PBF, thus showcasing the multifunctional benefits of Cu addition. So far, processing of Cu and its alloys via L-PBF remains challenging due to the high reflectivity and thermal conductivity of Cu, which reduce laser–powder interaction efficiency. Recent advances in laser source technology, powder surface modification, alloy design, in situ alloying, process optimization, and post-heat treatments have significantly improved the printability and functional performance of Cu-based materials. This review summarizes the advances in L-PBF of Cu and its alloys/composites, emphasizing powder characteristics, laser absorptivity, melt pool stability, defect formation, and microstructural evolution. It also critically evaluates elevated-temperature mechanical/thermal stability and anisotropy in mechanical, electrical, and thermal performance, and outlines future research directions and industrial prospects.