• Journal of the Korean institute of surface engineering
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• v.17 no.1
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• pp.7-13
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• 1984

Carburizing of a 12%Cr steel containing 0.6%Si was performed at 950$^{\circ}C$ for various times, and the microstructure, hardness and the water characteristics of the carburized chromium steel were examined. The results obtained in this study are as follows: 1. Carbide-dispersed layer (CD layer) with fine dispersion of $Cr_7C_3$ in martensite matrix was formed by carburizing. The radius and amount of the carbides in the surface region of CD layer were about 0.3${\mu}m$ and 35% by volume, respectively. 2. Chromium steel carburized and quench-tempered showed better wear resistance and hardness than ordinary high chromium tool steel. It is concluded from these results that fine dispered carbides are very effective in improving wear resistance and hardness.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.142-143
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• 2006

Recently, automotive engines have changed to the silent chain system in order to reduce noise and to improve reliability. High contact fatigue strength is needed for the sprockets of silent chain system. As a result, a high-contact-fatigue-strength P/M material was developed using the technology of surface rolling, which densifies the surface layer of sintered parts. It was established that the contact fatigue strength of the developed material was a great improvement over that of the conventionally used sintered material.