AISI H13 열간성형용 공구강의 기계적성질, 특히 강도와 인성을 향상시키기 위하여 급열처리를 적용하였다. 연구결과에 의하면 급열처리는 종래의 열처리 경우보다 항복강도는 10.7%, 인장강도는 12.6% 증가하였으며 파괴인성(Kc)의 값은 거의 변화가 없었다. 급열처리의 최적조건은 heating rate을 21.8℃/sec로 하여 austenitizing temperature에서 60sec 유지한 경우이다. 이와 같이 기계적성질의 향상, 특히 강도적 증가는 lath martensite 기지내에 석출된 미세한 탄화물의 분산강화에 의한 것으로 생각된다.

Rapid heat treatment has been applied to AISI H13 hot work tool steel for improving the mechanical properties, especially strength and toughness. Experimental result showed that the yield strength was increased by 10.7%, the ultimate tensile strength was increased by 12.6% and fracture toughness (Kc) values were maintained same level to compare with conventional heat treatment. It was found that the best rapid heat treatment condition was that heating rate was 21.8℃/sec, holding time was 60 sec at austenitizing temperature. It is believed that the improvement of mechanical properties, especially strength, was due to the dispersion strengthening of fine carbides precipitates within the lath martensite matrix.