Open AccessThe influence of carbon potential after gas-carbonitriding on the microstructure and fatigue behavior of low alloyed steel
Author(s) -
Abdelkarim Ghanem,
Mohamedali Terres
Publication year - 2022
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/ac4e3c
Subject(s) - tempering , carbonitriding , materials science , quenching (fluorescence) , metallurgy , fractography , microstructure , carbon steel , carbon fibers , scanning electron microscope , alloy , alloy steel , tetrafluoride , vickers hardness test , composite material , corrosion , analytical chemistry (journal) , chemistry , physics , chromatography , quantum mechanics , composite number , fluorescence
In this paper, the effects of gas-carbonitriding time on fatigue limit improvement of low alloy steel specimens were investigated by experimental tests of three points fatigue flexion. Besides, metallurgical evaluations and micro-Vickers hardness tests were performed employing metallographic techniques, optical, scanning electron microscopy and x-ray diffraction techniques. Test findings showed that this amount remarkably improved the components fatigue resistance. The fatigue life of carbonitrided specimens was prolonged between 16%, for CN11 (i.e. austenization-870°/7 h, atmosphere with 1% carbon potential, quenching-oil medium and tempering-200 °C/1 h), and 32%, for CN21(i.e. austenization-870°/8 h, atmosphere with 1, 2% carbon potential, quenching-oil medium and tempering-200 °C/1 h), compared to the untreated state. It is obvious, from the fractography analysis, utilizing (SEM), that fatigue cracks appeared first at the carbonitrided specimens surface.