The optimization of martensitic stainless steel composition to reduce hot tearing after laser powder bed fusion

Ultra-high strength martensitic stainless steel plays an essential role in aerospace, nuclear and other fields. This paper addresses laser-based powder bed fusion of martensitic stainless steel, based on thermodynamic software and computer languages for high-throughput calculation in combination with the hot tear sensitivity index criterion, Optimization of the alloy composed of Fe11Cr8Ni5Co3Mo martensitic stainless steel for resistance to hot tearing. The martensitic stainless steel composition with the lowest crack sensitivity was selected from hundreds of millions of data sets, reducing the hot tearing sensitivity index from 6841 to 1861. The alloy with the lowest hot tearing sensitivity was Fe11.3Cr8.18Ni2.0Mo2. 8Co0.24Mn0.02V0.02Si0.01C0.17Mg. The hot tearing sensitivity has been experimentally verified in conjunction with additive manufacturing, and a comparative study of the building state organization and mechanical properties has been made.(c) 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).