超高強度低合金TRIP型ベイニティックフェライト鋼板の温間成形性(力学特性)

概要

論文の詳細を見る
Forming temperature dependence of formability in 0.20C-1.51Si-1.51Mn ultra high-strength TRIP-aided sheet steels with bainitic ferrite matrix (TBF steel) which were austempered at 375 or 450℃ was investigated for automotive applications. Warm formings at 20-50℃ and 100℃ respectively enhanced the stretch-formability and the deep drawability of the TBF steel through the TRIP effect due to the strain-induced martensite transformation of retained austenite. The stretch-flangeability became maximum by warm forming at 20-50℃ and 100-200℃ in the TBF steels austempered at 375℃ and 450℃, respectively. Further good stretch-flangeability was completed by warm punching at 100-200℃ and subsequent cold expanding at 20℃ in the TBF steel austempered at 450℃. The mechanisms improving these formabilities by warm forming were proposed in terms of retained austenite characteristics and microstructural properties.
社団法人日本鉄鋼協会の論文
2005-02-01