Open AccessProperties of stainless-steel surface after hollow cathode assisted plasma nitriding
Author(s) -
Zhehao Zhang,
Yunjie Bi,
Minyi Zhang,
Yang Li,
F.S. Zhao,
Shangzhou Zhang,
Yongyong He
Publication year - 2020
Publication title -
materials research express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.383
H-Index - 35
ISSN - 2053-1591
DOI - 10.1088/2053-1591/abcbb7
Subject(s) - nitriding , materials science , indentation hardness , corrosion , cathode , metallurgy , scanning electron microscope , layer (electronics) , hardness , plasma , transmission electron microscopy , precipitation , phase (matter) , surface layer , microstructure , composite material , nanotechnology , chemistry , organic chemistry , meteorology , physics , quantum mechanics
AISI 304 stainless steel was nitrided at different temperature in the plasma equipment using a new auxiliary device. The proposed hollow cathode auxiliary device improves the plasma density, thereby accelerating the nitriding process. The modified surface was characterized by x-ray diffraction, scanning and transmission electron microscopies, atomic force microscopy, surface microhardness testing. Electrochemical corrosion test was used to measure the localized corrosion resistance of the samples. Single S-phase layer without the CrN precipitation was obtained by hollow cathode plasma nitriding at 450 °C, which improved the microhardness, wear and corrosion resistance of the steel surface. Nitriding at higher temperature of 550 °C resulted in substitution of the S-phase towards layer composed from CrN and α -Fe phases, improving the microhardness but decreasing the corrosion resistance.