Effect of Alloying Elements on Microstructures and Mechanical Properties of Bainitic Microalloyed Steels

베이나이트계 비조질강에서 미세조직과 기계적성질에 미치는 합금원소의 영향

Bainitic microalloyed steels have drawn a lot of attention because of high strength combined with high toughness. In order to process the alloys easily , it is necessary to get the alloys of high hardenability. Mo and B were added to enhance the hardenability, which was demonstrated by TTT simulation and microstructures. It was also identified using BNCT that B, hardenability raising element, was distributed more evenly as cooling rate went up. Examination of grain coarsening temperature depending upon austenitizing temperature revealed that V and Ti effectively inhibited the grain growth up to $1000^{\circ}C\;and\;1050^{\circ}C$ respectively.