Selective laser melting and heat treatment of precipitation hardening stainless steel with a refined microstructure and excellent mechanical properties

• DOI: 10.1016/j.scriptamat.2019.10.040
• Publication Date: 2019-11-09T16:33:04Z
• Authors: X.D. Nong; X.L. Zhou; J.H. Li; Y.D. Wang; Y.F. Zhao; M. Brochu
• Keywords: Precipitation hardening; Selective Laser Melting; Ductility (Earth science); Hardening (computing); Heat treating

Abstract In this study, we concentrated on the microstructural characteristics and mechanical properties of precipitation hardening (PH) stainless steel 15-5PH via Selective laser melting (SLM). A large amount of retained austenite was observed in the as-built samples which contribute to excellent ductility. The amount of retained austenite reduced greatly after heat treatment and the remaining minor retained austenite completely transformed to martensite during tensile process. A finer grain structure and a concentration of dislocations around the inclusions and at the submicron grain boundaries following heat treatment promoted SLM 15-5PH to demonstrate a higher strength than those of wrought samples.