Abstract
The paper presents the study of the diffusion phenomenon in metallic materials and its application in the carburizing process of hypoeutectoid steels. The fundamental mechanisms of atomic diffusion are analyzed, namely vacancy diffusion and interstitial diffusion, as well as the influence of temperature on atomic mobility. Based on Fick’s second law, non-steady-state diffusion is addressed, establishing the relationship between concentration, time, and the penetration depth of the diffusing element.
The theoretical study is complemented by a calculation example of the time required for carburizing a steel with 0.25% C, in order to obtain a carbon concentration of 0.80% at a depth of 0.5 mm, at a temperature of 950°C. The obtained result indicates a treatment time of approximately 7 hours.
In the experimental part, carburizing of a C22 steel in a methane atmosphere was carried out, followed by metallographic analysis. The microstructure shows the formation of a carburized surface layer consisting of high-carbon martensite, a transition zone with a mixed structure, and a ferrite-pearlite core. The high hardness of the surface layer confirms the effectiveness of the treatment.
The results demonstrate that the carburizing process enables an optimal balance between surface hardness and core toughness.
The theoretical study is complemented by a calculation example of the time required for carburizing a steel with 0.25% C, in order to obtain a carbon concentration of 0.80% at a depth of 0.5 mm, at a temperature of 950°C. The obtained result indicates a treatment time of approximately 7 hours.
In the experimental part, carburizing of a C22 steel in a methane atmosphere was carried out, followed by metallographic analysis. The microstructure shows the formation of a carburized surface layer consisting of high-carbon martensite, a transition zone with a mixed structure, and a ferrite-pearlite core. The high hardness of the surface layer confirms the effectiveness of the treatment.
The results demonstrate that the carburizing process enables an optimal balance between surface hardness and core toughness.
Cuvinte cheie
carburizing
diffusing
Fick law
martensite
hardness
Istoric articol
Publicat
01.04.2026
Informații autori
Citare recomandată
Florin CIOFU (2026). Study Of the Carburization of a Hypoeutectoid Steel (~0.20% C) And Its Influence on Microstructure. Journal of Fiability and Durability, 1(1), 365–371. https://doi.org/10.65631/JFD.1(37).2026.43
Referințe bibliografice
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