Open AccessStructural Changes of Nitrogen Ferrite After Aging in Temperature Interval up to 100 °С
Author(s) -
Tatyana Mechkarova,
Yaroslav Argirov,
Daniela Spasova,
Aneliya Stoyanova
Publication year - 2021
Publication title -
the annals of "dunărea de jos" university of galaţi. fascicle ix, metallurgy and material science
Language(s) - English
Resource type - Journals
eISSN - 2668-4756
pISSN - 2668-4748
DOI - 10.35219/mms.2021.1.04
Subject(s) - materials science , carbonitriding , ferrite (magnet) , metallurgy , hardening (computing) , nitrogen , composite material , layer (electronics) , chemistry , organic chemistry
This paper aims to determine the extent of aging of nitrogen ferrite at temperatures below 100 °C and the structural and strength changes that occur in the process. The tests are carried out on samples of technically pure iron (Armco). The specimens are pre-deformed by tension and re-crystallisation heating to achieve a large-grain ferrite structure. A large-grained structure has been chosen to more accurately track the change in micro-hardness of the individual grains during the aging process. Nitric ferrite results from gas carbonitriding and subsequent hardening. Upon hardening, the samples are stored in a refrigerator, and then the surface layer formed is removed through electrochemical corrosion. Afterwards, aging heat treatment at temperatures below 100 °C is undertaken. After the aging process, micro-hardness of the individual grains is examined and X-ray structural analysis is performed.