Microstructure and Mechanical Properties of High-Nitrogen Austenitic Stainless Steels Subjected to Equal-Channel Angular Pressing

• Published in: Acta metallurgica sinica : English letters 2016-02, Vol.29 (2), p.140-149
• Main Authors: Dong, Fu-Yuan, Zhang, Peng, Pang, Jian-Chao, Duan, Qi-Qiang, Ren, Yi-Bin, Yang, Ke, Zhang, Zhe-Feng
• Format: Article
• Language: English
• Subjects: Austenitic stainless steels; Characterization and Evaluation of Materials; Chemistry and Materials Science; Corrosion and Coatings; Deformation; Elongation; Equal channel angular pressing; Hardening rate; Materials Science; Mechanical properties; Metallic Materials; Microscopy; Microstructure; Nanotechnology; Nitrogen; Organometallic Chemistry; Shear strain; Single crystals; Spectroscopy/Spectrometry; Stainless steel; Tribology; Yield stress; 力学性能; 加工硬化率; 均匀伸长率; 挤压过程; 显微组织; 等径; 高氮不锈钢; 高氮奥氏体不锈钢
• ISSN: 1006-7191; 2194-1289
• DOI: 10.1007/s40195-016-0370-9

Three high-nitrogen stainless steels with different N contents were successfully processed by equal-channel angular pressing for one pass, and their microstructures and mechanical properties were investigated. It was found that the microstructure of the billet was heterogeneous across the billet thickness, resulting in the difference in the mechanical properties due to the different deformation conditions. A relatively low strength, high uniform elongation, and high work- hardening rate for the samples at the bottom of the billet was achieved in comparison with those processed at the top. Meanwhile, it was observed that the density of deformation twins increased with the content of N; accordingly, the strength and elongation of the alloys increase with the content of N, resulting in a good strength-ductility combination.