(1. Faculty of Materials and Metallurgical Engineering, Kunming University of Science and Technology, Kunming 650093, Yunnan, China 2. Institute for Structure Materials, Central Iron and Steel Research Institute, Beijing 100081, China
Abstract:The intercritical annealing time effects on the microstructure, mechanical properties and hole expansion capacity of the cold rolled medium manganese steel(0.1C-5Mn) was studied. The microstructure evolution during annealing was examined by SEM and EBSD. The strength, ductility and hole expansion were measured by tensile and hole expansion test. It was found that an equiaxed ultrafine ferrite and austenite structure was developed due to the austenite-reverted transformation in the annealing process(ART-annealing) at 650℃, product of strength to ductility attained over 30GPa·%. The austenite volume fraction increased with increasing of the annealing time, but over-increased austenite fraction was detrimental to the hole expansion capacity.
K-i Suimoto , K Nakano , S-M Song , et al.. Retained austenite characteristics and stretche-flangeability of high-strength low-alloy TRIP type bainitic sheet steels[J].ISI J Intern,2002,42(4):450-
[4]
K-i Suimoto , K Nakano , S-M Song , et al.. Retained austenite characteristics and stretche-flangeability of high-strength low-alloy TRIP type bainitic sheet steels[J].ISI J Intern,2002,42(4):450-
[5]
K-i Sugimoto , R Kikuchi , M Tsunezawa , et al. .The effects of heat-treatment conditions on stretch- flange-ability and bendability of high-strength low alloy TRIP-aided sheet steels with annealed martensitic matrix[J].Journal of the Iron and Steel Institute of Japan,2003,89(10):1065-
[5]
K-i Sugimoto , R Kikuchi , M Tsunezawa , et al. .The effects of heat-treatment conditions on stretch- flange-ability and bendability of high-strength low alloy TRIP-aided sheet steels with annealed martensitic matrix[J].Journal of the Iron and Steel Institute of Japan,2003,89(10):1065-
[6]
D I Hyun , S M Oak , S S Kang , Y H Moon.Estimation of hole flangeability for high strength steel plates[J].J.Mater.Proc.Technol,2002,130-131(20):9-
[6]
D I Hyun , S M Oak , S S Kang , Y H Moon.Estimation of hole flangeability for high strength steel plates[J].J.Mater.Proc.Technol,2002,130-131(20):9-
[7]
R. Narayanasamy & C. Sathiya Narayanan & Palani Padmanabhan & T. Venugopalan.Effect of mechanical and fractographic properties on hole expandability of various automobile steels during hole expansion test[J].Int J Adv Manuf Technol,2010,47(1-4):365-
[7]
R. Narayanasamy & C. Sathiya Narayanan & Palani Padmanabhan & T. Venugopalan.Effect of mechanical and fractographic properties on hole expandability of various automobile steels during hole expansion test[J].Int J Adv Manuf Technol,2010,47(1-4):365-
[8]
X.Fang ,ZFana, B. Ralpha, P. Evans, R. Underhill.Effects of tempering temperature on tensile and hole expansion properties of a C–Mn steel[J].Journal of Materials Processing Technology,2003,132:215-
[8]
X.Fang ,ZFana, B. Ralpha, P. Evans, R. Underhill.Effects of tempering temperature on tensile and hole expansion properties of a C–Mn steel[J].Journal of Materials Processing Technology,2003,132:215-
Jie Shi, Xinjun Sun, Maoqiu Wang, Weijun Hui, Han Dong and Wenquan Cao*.Enhanced work-hardening behavior and mechanical properties inultra?ne-grained steels with large-fractioned metastable austenite[J].Scripta Materialia,2010,63(8):815-
[11]
Jie Shi, Xinjun Sun, Maoqiu Wang, Weijun Hui, Han Dong and Wenquan Cao*.Enhanced work-hardening behavior and mechanical properties inultra?ne-grained steels with large-fractioned metastable austenite[J].Scripta Materialia,2010,63(8):815-
[12]
Yoshimasa FUNAKAWA,Tsuyoshi SHIOZAKI,Kunikazu,TOMITO,Tetsuo YAMAMOTO and Eiji MAEDA.Development of High Strength HOT-rolled Sheet Steel Consisting of Ferrite and Nanometer-sized Carbides[J].ISIJ International,2004,44(11):1945-
[12]
Yoshimasa FUNAKAWA,Tsuyoshi SHIOZAKI,Kunikazu,TOMITO,Tetsuo YAMAMOTO and Eiji MAEDA.Development of High Strength HOT-rolled Sheet Steel Consisting of Ferrite and Nanometer-sized Carbides[J].ISIJ International,2004,44(11):1945-