Optimization of grain boundary engineering (GBE) process is explored in a Fe–20Cr–19Mn–2Mo–0.82 N high-nitrogen and nickel-free austenitic stainless steel, and its intergranular corrosion (IGC) property after GBE treatment is experimentally evaluated. The proportion of low Σ coincidence site lattice (CSL) boundaries reaches 79.4% in the sample processed with 5% cold rolling and annealing at 1423 K for 72 h; there is an increase of 32.1% compared with the solution-treated sample. After grain boundary character distribution optimization, IGC performance is noticeably improved. Only Σ3 boundaries in the special boundaries are resistant to IGC under the experimental condition. The size of grain cluster enlarges with increasing fraction of low ΣCSL boundaries, and the amount of Σ3 boundaries interrupting the random boundary network increases during growth of the clusters, which is the essential reason for the improvement of IGC resistance.

中文翻译：

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晶界工程在提高Fe-Cr-Mn-Mo-N高氮和无镍奥氏体不锈钢的晶间腐蚀性能中的应用

在Fe–20Cr–19Mn–2Mo–0.82 N高氮和无镍奥氏体不锈钢中探索了晶界工程（GBE）工艺的优化，并通过实验评估了其在GBE处理后的晶间腐蚀（IGC）性能。在5％冷轧和1423 K退火72 h的样品中，低Σ符合位点晶格（CSL）边界的比例达到79.4％。与固溶处理的样品相比，增加了32.1％。经过晶界特征分布优化，IGC性能得到明显改善。在实验条件下，只有特殊边界中的Σ3边界才能抵抗IGC。低ΣCSL边界的比例越大，晶粒团簇的尺寸越大，