COMPARISON OF SALT BATH PREOXIDATION AND AIR PREOXIDATION FOR SALT BATH NITRIDING

Autor: Wenchen Mei, Jiqiang Wu, Mingyang Dai, Kunxia Wei, Jing Hu
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Acta Metallurgica Slovaca, Vol 25, Iss 2 (2019)
Druh dokumentu: article
ISSN: 1335-1532
1338-1156
DOI: 10.12776/ams.v25i2.1271
Popis: Salt bath preoxidation was primarily conducted prior to salt bath nitriding, and the effect on salt bath nitriding was compared with that of conventional air preoxidation. Characterization of the modified surface layer was made by means of optical microscopy, scanning electron microscope (SEM), micro-hardness tester and x-ray diffraction (XRD). The results showed that the salt bath preoxidation could significantly enhance the nitriding efficiency. The thickness of compound layer was increased from 13.3μm to 20.8μm by salt bath preoxidation, more than 60% higher than that by conventional air preoxidation under the same salt bath nitriding parameters of 560℃ and 120min. Meanwhile, higher cross-section hardness and thicker effective hardening layer were obtained by salt bath preoxidation, and the enhancement mechanism of salt bath preoxidation was discussed.
Databáze: Directory of Open Access Journals