Effects of Mn Content on the Warm Stretch-Flangeabiliy of C-Si-Mn TRIP-Aided Steels

Autor: Junya Kobayashi, Shin-nosuke Hidaka, Koh-ichi Sugimoto, Hikaru Tanino
Rok vydání: 2017
Předmět:
Zdroj: steel research international. 88:1600482
ISSN: 1611-3683
DOI: 10.1002/srin.201600482
Popis: Effects of Mn content on warm stretch-flangeability are investigated using 0.2%C–1.5%Si–(1.5–5.0)% Mn transformation-induced plasticity (TRIP)-aided sheet steels with annealed martensite matrix. Warm hole-expansion at 150–250 °C after hole-punching at 25 °C enhances the stretch-flangeability of 3 and 5% Mn steels. The warm stretch-flangeability increases with the Mn content. The superior warm stretch-flangeability of hole-punched 5% Mn steel is caused by its large localized ductility on expanding, which results primarily from the stabilization of its large quantity of retained austenite and its fine microstructure. Use of hole-drilling instead of hole-punching at 25 °C further increases the stretch-flangeability and raises the optimum expanding temperature to 250–300 °C.
Databáze: OpenAIRE