The Journal of
the Korean Journal of Metals and Materials

The Journal of
the Korean Journal of Metals and Materials

Monthly
  • pISSN : 1738-8228
  • eISSN : 2288-8241

Editorial Office

Title Research Paper - Transformations - : The Effect of Microstructures on the Strength and Impact Properties of Micro - alloyed Forging Steels in Low - carbon Martensitic Grade
Authors 이덕락(D . L . Lee); 박성운(S . W . Park); 주웅용(W . Y . Choo)
Page pp.560-568
ISSN 0253-3847
Abstract The development of microstructures in micro alloyed forging steels was controlled by applying different cooling rate after hat rolling. The water quenching led to the formation of lath and auto-tempered martensite while the air cooling resulted in bainite and M-A constituents. As the cooling rate increased, the size of M-A constituents decreases and the constituents elongated to the specific direction. Since high carbon twinned martensites in the air cooled specimen caused the brittle fracture, the air cooled specimen showed a low toughness.