Acta Metallurgica Sinica (English Letters) ›› 2017, Vol. 30 ›› Issue (11): 1080-1088.DOI: 10.1007/s40195-017-0647-7

Special Issue: 2017年钢铁材料专辑

• Orginal Article • Previous Articles     Next Articles

Hot Workability of the as-Cast 21Cr Economical Duplex Stainless Steel Through Processing Map and Microstructural Studies Using Different Instability Criteria

Jing Han1,*(), Jia-Peng Sun2,*(), Ying Han3, Huan Liu2   

  1. 1 School of Mechanical and Electrical Engineering, China University of Mining and Technology, Xuzhou 221116, China
    2 College of Mechanics and Materials, Hohai University, Nanjing 210098, China
    3 Key Laboratory of Advanced Structural Materials, Ministry of Education, Changchun University of Technology, Changchun 130012, China
  • Received:2017-09-13 Revised:2017-09-13 Online:2017-11-20 Published:2018-01-30
  • Contact: Han Jing,Sun Jia-Peng

Abstract:

To develop a fundamental understanding of the flow behavior and optimal hot workability parameters of this material, the hot workability and deformation mechanisms of the as-cast 21Cr EDSS were studied using processing map technology combined with microstructure analysis and isothermal hot compression over the temperature range of 1000-1150 °C and strain rate range of 0.01-10 s-1. The processing maps and constitutive equation of peak stress were developed based on Prasad’s and Murty’s criteria. The results show that the processing maps exhibit a stable domain at 1000-1150 °C and 0.01-1 s-1. The instability domain is exhibited at high strain rates (≥1 s-1). This implies that Murty’s criterion can predict the unstable domain with high reliability. The detailed deformation mechanisms are also studied by microstructure observation, showing that the flow localization and microcracking are responsible for the flow instability.

Key words: Duplex stainless steel, Constitutive relationship, Processing map, Hot deformation behavior