Proceedings of the Korean Society for Technology of Plasticity Conference (한국소성가공학회:학술대회논문집)
- 2008.05a
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- Pages.431-434
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- 2008
Effects of microstructure on impact transition temperature of low carbon HSLA steels
저탄소 HSLA강의 천이 온도 미치는 미세 조직의 영향
- Published : 2008.05.08
Abstract
Effects of microstructure on the toughness of low carbon HSLA steels were investigated. Nickel decreased the ferrite-austenite transformation temperature, resulted in increase of the fraction of bainitic ferrite. However, it was decreased with increasing deformation amount at austenite region. Since fine austenite grains formed by dynamic recrystallization under large strain transformed to acicular ferrite or granular bainite rather than bainitic ferrite. The effective grain size, thus, was decreased by deformation and it resulted in lower ductile-brittle transition temperature (DBTT). The bainitic ferrite was thought to inhibit the fracture crack initiation and to delay the crack propagation by its high dislocation density and hard interlath