文献类型：期刊文献

英文题名：Scale-Up Fabrication of Gradient Structures in Austenitic Stainless Steels Achieves a Simultaneous Increase in Strength and Toughness

作者：Huang, Minghao[1]; Wang, Lingyu[1]; Yuan, Sen[1]; Wang, Jinliang[2]; Wang, Chenchong[1]; Mogucheva, Anna[3]; Xu, Wei[1]

机构：[1] State Key Laboratory of Rolling and Automation, School of Materials Science and Engineering, Northeastern University, Shenyang, 110819, China; [2] School of Mechanical and Power Engineering, Guangdong Ocean University, Zhanjiang, 524000, China; [3] Laboratory of Mechanical Properties of Nanoscale Materials and Superalloys, Belgorod State University, Belgorod, 308015, Russia

年份：2022

外文期刊名：SSRN

收录：EI(收录号：20220121311)

语种：英文

外文关键词：Austenite - Building materials - Cracks - Deformation - Economic and social effects - Fabrication - Grain size and shape - Martensite - Plasticity - Safety engineering - Strain hardening - Strengthening (metal) - Tensile strength

外文摘要：Simultaneous strengthening and toughening of austenitic stainless steel are of great importance in safety-critical applications. Gradient structured steels have thus attracted significant interest as they can achieve unprecedented strength and toughness synergy. However, the traditional fabrication process of gradient metals is relatively complex and limited to small depths of gradient. In this contribution, we have developed a novel processing route consisting of inhomogeneous rolling and annealing to fabricate a large gradient profile (~5 mm) in the austenite grain size. The fabricated bulk gradient austenitic steel exhibits higher tensile strength (675 MPa) and Charpy impact energy (11.8 J) compared with the uniform-grain-size structural steel (644 MPa and 10.9 J, and 601 MPa and 11.3 J for fine grained (FG) and coarse grained (CG) steels). The deformation mechanisms of the bulk gradient austenitic steel were further explored. The combined contribution of the hetero-deformation induced (HDI) strengthening and transformation-induced plasticity (TRIP) effect results in the ideal work-hardening capability and tensile strength of the gradient austenitic steel. Thanks to the deep gradient, the fraction of deformation-induced martensite decreases along the fabricated gradient. The pronounced TRIP effect near the coarse-grained V-notch improves the crack initiation energy (Ei), while the less martensite formed in the fined-grained interior raises the crack propagation energy (Ep). This study provides new insights into the circumvention of the strength-toughness trade-off and the fabrication of gradient structured steels with a large gradient profile. ? 2022, The Authors. All rights reserved.