Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (29권4호 268-277)

A Study on the Boronizing treatment of the microalloyed steel

비조질강의 Boronizing 처리에 관한 연구

김강형;선명숙;윤재홍;변응선;권동일;

창원대학교 공과대학 재료공학과;한국기계연구원;서울대학교 공과대학 재료공학부;

Abstract

Boronizing treatment of Microalloyed steel has been investigated by mean of Boronizing paste mainly consisted of $B_4C$ at various temperatures and times. The micro hardness of the boride layers were about HV 1200~1500. The thickness of the boride layer were increased with an increase of square root of treatment time at constant temperature. The activation energy for diffusion of boron in the specimen obtained from the slope of Arrhenius plots was 254 kJ/mol, but 197 kJ/mol for the induction heated specimen. The boride layer had a good corrosion resistance in solutions of 20% HCl and 20% $H_2SO_4$, solution. In 20% $HNO_3$ solution, however, its corrosion resistance increased. The boride layer had a good high temperature oxidation resistance at below $800^{circ}C$, but at temperature above $900^{circ}C$, the oxidation resistance decreased as the oxidation temperature.

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