Research Progress and Prospect of Laser Additive Manufacturing of Ultra-High-Strength Steel

Ultra-high-strength steels (UHSSs) exhibit exceptional strength and toughness, making them widely utilized in aerospace and other industries. This paper reviews the progress in metal additive manufacturing and analyzes the microstructure, properties, and strengthening mechanisms of laser additive manufacturing for three types of UHSSs: low alloy ultra-high-strength steel (LUHSS), medium alloy ultra-high-strength steel (MUHSS), and high-alloy ultra-high-strength steel (HUHSS). The impact of process parameters on performance is discussed, along with a comprehensive evaluation of the advantages and disadvantages of additive manufacturing for different steel grades, focusing on printability, economic viability, and mechanical properties. Finally, the unresolved challenges in the current laser additive manufacturing processes for UHSS are identified, and future research directions are proposed.