| Abstract Scope |
Next-generation nuclear reactors demand materials capable of withstanding elevated operating temperatures over extended service lives, ensuring efficient, safe, and reliable structural performance. This study investigates the microstructure, and mechanical properties of Grade 92 ferritic/martensitic stainless steels fabricated by laser powder directed energy deposition. Three different heat treatments were performed: solution annealed (SA: 1070°C, 15 mins), precipitation treatment (PT: 775°C, 45 mins), and a combination of SA followed by PT. Electron microscopy results showed significant grain boundary precipitates after both the PT, and SA+PT while no such precipitations were observed after SA. Energy-dispersive spectroscopy mapping revealed that these precipitates were enriched in Cr, Mn, W, V, and C. The SA treatment showed Vickers hardness of 456. 68 ± 4.31 HV while the sample after SA+PT treatment showed the lowest hardness of 246 ± 3 HV. Tensile properties (room temperature and 550°C) of the as deposited and after PT are discussed. |