1. Central Iron and Steel Research Institute, Beijing 100081, China 2. School of Materials Science and Engineering,Huazhong University of Science and Technology, Wuhan 430074, Hubei, China 3. Danish��Chinese Centre for Nanometals, Section for Materials Science and Advanced Characterization, Department of Wind Energy, Technical University of Denmark, DK��4000 Roskilde, Denmark
High Ductility and Toughness of a Micro��duplex Medium��Mn Steel in a Large Temperature Range from -196 �� to 200 ��
1. Central Iron and Steel Research Institute, Beijing 100081, China 2. School of Materials Science and Engineering,Huazhong University of Science and Technology, Wuhan 430074, Hubei, China 3. Danish��Chinese Centre for Nanometals, Section for Materials Science and Advanced Characterization, Department of Wind Energy, Technical University of Denmark, DK��4000 Roskilde, Denmark
ժҪ A medium��Mn steel (0��2C5Mn) was processed by intercritical annealing at different temperatures (625 �� and 650 ��). An ultrafine��grained micro��duplex structure consisting of alternating austenite and ferrite laths was developed by austenite reverse transformation (ART) during intercritical annealing after forging and hot rolling. Ultrahigh ductility with a total elongation higher than 30% was achieved in the temperature range from -196 �� to 200 ��, and high impact toughness no less than 200 J at -40 �� was obtained. Based on the analysis of microstructure and mechanical properties, it was found that the enhanced ductility was determined by the phase transformation effect of austenite (TRIP effect), while the delayed ductile to brittle transition was controlled by austenite stability.
Abstract��A medium��Mn steel (0��2C5Mn) was processed by intercritical annealing at different temperatures (625 �� and 650 ��). An ultrafine��grained micro��duplex structure consisting of alternating austenite and ferrite laths was developed by austenite reverse transformation (ART) during intercritical annealing after forging and hot rolling. Ultrahigh ductility with a total elongation higher than 30% was achieved in the temperature range from -196 �� to 200 ��, and high impact toughness no less than 200 J at -40 �� was obtained. Based on the analysis of microstructure and mechanical properties, it was found that the enhanced ductility was determined by the phase transformation effect of austenite (TRIP effect), while the delayed ductile to brittle transition was controlled by austenite stability.
��������:National Natural Science Foundation of China (NSFC);National Basic Research Program of China (973 Program);Danish National Research Foundation;National Natural Science Foundation of China
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E-mail: hujun-jay2004@163.com
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Si��lian CHEN,Jun HU,,Xiao��dan ZHANG,Han DONG,Wen��quan CAO. High Ductility and Toughness of a Micro��duplex Medium��Mn Steel in a Large Temperature Range from -196 �� to 200 ��[J]. �й������ڿ���, 2015, 22(12): 1126-1130.
Si��lian CHEN,Jun HU,,Xiao��dan ZHANG,Han DONG,Wen��quan CAO. High Ductility and Toughness of a Micro��duplex Medium��Mn Steel in a Large Temperature Range from -196 �� to 200 ��. Chinese Journal of Iron and Steel, 2015, 22(12): 1126-1130.
2015, Vol. 22 
