Enhancement of Mechanical Properties of Mild Steel via Carburization Process using Residual Carbon Black
Date
2021-03-30
Authors
Ata, Ghofran
Jazi, Mosheera
Manasra, Raghad
Journal Title
Journal ISSN
Volume Title
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Abstract
Abstract
Car tires are the most solid waste that is produced globally every year. Nowadays, there
is a tendency to improve the economic value of tire wastes as a source for producing
several products, such as carbon black (CB), by pyrolysis process. In this research, the
CB was used as a carbon source in pack carburization for mild steel (0.139 %C). So,
the effect of the carburization temperature and holding time were studied on the
hardness and fatigue characteristics of mild steel by carburizing it with 90% of CB as
carburizer and 10% of Na2 CO3 as an energizer, after that, it was quenched in water,
then tempered at 550 °C for 1 h. In the first, the mild steel specimens were carburized
at different temperatures (850, 900, and 950 °C) for constant time (2 h), the results
showed that the surface hardness of carburized mild steel increased with increasing
temperature. Then the effect of carburization time was studied at a constant temperature
of 950 °C, the different times were 1.5 and 2.5 h, in addition to 2 h. Also, the surface
hardness of carburized mild steel has been increased with increasing the soaking time.
Besides, the fatigue life of carburized mild steel has been improved almost 10 times
than untreated specimens. For the sake of comparison, commercial charcoal was used
as a carbon source for carburizing mild steel at 950 °C for different times (2 and 2.5 h).
The surface Vickers hardness of carburized steel by charcoal (820 HV) was better than
carburized steel by CB (564.1 HV), however, the hardness of untreated specimen 260.5
HV. For the fatigue life for carburized specimens by charcoal, they need further study
by re-conducting their experiments and tests as they differ in their results from what is
found in the literature.
Keywords: Mild steel; residual carbon black; pyrolysis; pack carburization; hardness;
fatigue resistance.