Dynamic Recrystallization Kinetics of Cu-0.36Cr-0.03Zr Alloy During Hot Compression
- PDF / 2,622,751 Bytes
- 10 Pages / 593.972 x 792 pts Page_size
- 100 Downloads / 156 Views
JMEPEG DOI: 10.1007/s11665-017-2701-z
Dynamic Recrystallization Kinetics of Cu-0.36Cr-0.03Zr Alloy During Hot Compression Guoliang Ji, Fangli Qin, Liyuan Zhu, Qiang Li, and Lei Li (Submitted June 21, 2016; in revised form December 24, 2016) Based on compression tests in the temperature range of 800-950 °C and the strain rate range of 0.00120 s21 on a Gleeble-3500 thermomechanical simulator, the dynamic recrystallization (DRX) kinetics of Cu0.36Cr-0.03Zr alloy is developed by further analysis of true stress-strain curves and by investigating microstructures under different deformation conditions. The kinetics of dynamic recrystallization is expressed as the modified JMAK model, and effects of varying strain rate and temperature on the model parameters, including the critical strain, peak strain and materials constant kd, are investigated. The complete DRX grain size is described as a power law function of Zener-Hollomon parameter (Z), and it agrees well with the experimental data. Keywords
Compression tests, Cu-Cr-Zr alloys, dynamic recrystallization, microstructure
1. Introduction Work hardening (WH), dynamic recovery (DRV) and dynamic recrystallization (DRX) are important physical metallurgy phenomena in hot working of metal materials, and dynamic recrystallization easily occurs for metals and alloys with low-to-medium stacking fault energy, such as fcc metals, copper alloys and nickel alloys. In industrial production, dynamic recrystallization is used as an important method to improve microstructure and to obtain fine and homogenous grains. Therefore, it is significant to reveal the evolution mechanism of dynamic recrystallization of metals or alloys for manufacturing parts with the fine microstructure and excellent mechanical properties. So far dynamic recrystallization behaviors of metals or alloys have been extensively studied, and several models for the recrystallization kinetics and microstructure evolution were proposed (Ref 1-4). These models can be mainly divided into two categories: phenomenological model and physically based internal variable model. Phenomenological model describes the evolution of the recrystallization volume in the form of the Avrami equation, in which parameters to be determined are usually represented as a function of initial grain size, temperature, strain and strain rate. Phenomenological models have been widely adopted by commercial FEM software, such as FORGE and Deform-3D, to simulate recrystallization evolution of metals or alloys. Loyda et al. (Ref 5) established kinetics models of dynamic recrystallization (DRX), metadynamic recrystallization (MDRX), static recrystallization (SRX) and grain growth for a Ni-Fe-based
Guoliang Ji, Fangli Qin, Liyuan Zhu, and Qiang Li, School of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China; and Lei Li, School of Mechanical Engineering, Shanghai Dian Ji University, Shanghai 201306, China. Contact e-mails: [email protected] and [email protected].
Journal of Materials Engineering and Performance
superall
Data Loading...
