Research Progress on HR-2 Hydrogen Resistant Steel Formed by Laser Powder Bed Fusion

HR-2 hydrogen resistant steel has excellent hydrogen embrittlement resistance and is often used to make hydrogen storage pressure vessel. The development of laser powder bed fusion provides the possibility of preparing lightweight and irregularly-shaped hydrogen storage containers. The laser powder bed fusion forming of HR-2 hydrogen resistant steel is not yet mature. The effects of powder raw materials （particle size distribution, chemical composition and recyclability）, forming processes （energy density and scanning strategy） and post-treatment （surface treatment and heat treatment） on the performance of formed parts are summarized, the shortcomings of the current research are pointed out and the future development direction is outlined.