1. College of Materials Science and Engineering; Chongqing University; Chongqing 400044 P. R. China
2. National Engineering Research Center for Equipment and Technology of Cold Strip Rolling; Yanshan University; Qinhuangdao 066004 P. R. China
3. Department of Materials Science and Engineering; Kyoto University; Kyoto 606-8501 Japan
4. Section of Materials Science and Advanced Characterization, Wind Energy Department; Technical University of Denmark; DK-4000 Roskilde Denmark