Nitriding Effect of NaNO₃ Salt in Duplex Stainless Steel

Abstract:

Duplex stainless steel was nitrided by sodium nitrate, NaNO₃, salt bath from 592°C to 650°C for 1 to 10 hours. The microstructure, microhardness and tensile strength were investigated after nitriding of duplex stainless steel sheets. Microhardness of sample was increased from 279.7 HV to 296 HV after nitriding in bath of NaNO₃+4.8%NaCl salt at 650°C for 8 hours. Tensile strength was increased from 880 to 939.36 MPa and elongation of duplex stainless steel sheet was decreased from 42% to 38% after nitriding in salt bath of NaNO₃ at 650°C for 8 hours. The nitriding effect of NaNO₃ salt is similar with KNO₃ salt in duplex stainless steel sheet. NaNO₃ salt is cheaper than KNO₃ salt. Therefore, NaNO₃ salt is more economical than KNO₃ salt to nitride duplex stainless steel.

• Periodical: Applied Mechanics and Materials (Volume 851)
• Pages: 106-111
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.851.106
• Online since: August 2016
• Authors: Jamshid D. Shurdjanov, In Soo Kim*
• Keywords: Duplex Stainless Steel, Hardness, NaNO₃ Bath, Nitriding, Tensile Stress

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