Study on Dynamic Strain Aging Behavior of 92W-5Co-3Ni Alloy at Different Strain Rates and Temperatures
摘要
The study is mainly focused on understanding the compressive deformation behavior of 92W-5Co-3Ni alloy at different strain rates (0.001, 1, 25, 50, 75, 100 s−1) and temperatures ranging from room temperature (RT) to 800 °C at an interval of 200 °C. The flow stress behavior is sensitive to temperature and strain rate change. The flow stress increases at higher strain rates and lower temperature conditions. The serrated flow stress behavior has been noticed for 0.001 and 25 s−1 strain rates and high temperatures 200-600 °C conditions due to dynamic strain aging (DSA) phenomena. The types of serrated flow behavior have been examined at different strain rates and temperatures. The various mechanical properties, such as yield strength and hardness, have been evaluated. The maximum yield strength and hardness are found as 1744.7 MPa and 668 HV, respectively, at RT and 100 s−1 strain rate. The unusual rise in the yield strength and hardness has been observed in the temperature region of 200-600 °C and strain rates 0.001, and 25 s−1. The presence of DSA is also confirmed with negative strain rate sensitivity in this region. Finally, various microstructural parameters, such as grain size, W/W contiguity, dihedral angle, and neck length, are determined and the influence of DSA on these parameters is identified.