Temperature and Strain Rate Dependent Anisotropic Plastic Deformation Behavior of AZ31B Mg Alloy

In the present study, the plastic deformation of commercially available AZ31B alloy at different temperatures (300K-473K) and strain rates (0.1s-1-0.01s-1-0.001s-1) under uniaxial tensile test has been carried out. Three different sheet orientations, viz., rolling direction (RD), transverse direction (TD), and 45° to rolling direction have been used. The outcomes of the experiments have demonstrated a temperature-dependent relationship between mechanical properties such as yield strength, ultimate tensile strength, and percentage elongation. The yield strength and ultimate tensile strength has decreased by 28.58% and 31.03% respectively as temperature increased from 300 K to 473 K. At elevated temperature (473 K) the material has exhibited highest ductility (64.88%) as compare to 300 K. The hardening exponent has been found to decrease with increasing temperature. The flow stress behaviour has been predicted using work hardening models such as the Hollomon and Ludwik. Two-stage work hardening behavior has been observed at all the temperatures. According to statistical parameter comparison, Ludwik equation prediction capability of correlation coefficient (0.9959) has been found to be best in agreement with the experimental results

Studies on flow stress behaviour prediction of AZ31B alloy: Microstructural evolution and fracture mechanism

The hot tensile flow behaviour of the AZ31B alloy is investigated at various varying deformation temperatures (200–350 °C) and strain rates (0.1s−1, 0.01s−1, and 0.001s−1). The deformation condition significantly influenced the mechanical properties and microstructural evolution. Observation from the tensile tests indicated a strong dependence of flow stress on deformation temperature and strain rates. At a constant strain rate, flow stress decreased as the temperature increased, while at a constant deformation temperature, flow stress decreased with decreasing strain rates. The strain rate sensitivity varies from 0.01 to 0.25, suggesting a diffusion-controlled dislocation climb mechanism. Dynamic recrystallization (DRX) initiation was observed at 250 °C and a strain rate of 0.001s−1, characterized by the formation of necklace-type grains with low pole intensity. Predominantly, the DRX softening mechanism, including continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX), was observed at 350 °C and 300 °C for a strain rate of 0.001s−1. Fracture morphology analysis of the tested samples indicated a micro-void coalescence mechanism. Equiaxed dimples were found at 350 °C and a strain rate of 0.001s−1, while oval-shaped dimples were observed at 300 °C and 0.1s−1. A strain-compensated Arrhenius model was incorporated to estimate the flow stress prediction for hardening and softening regions. Statistical parameters such as the average absolute relative error (AARE = 13.50) and coefficient of determination (R = 0.97) were calculated. Good agreement between experimental and prediction stresses was achieved at a 0.001s−1 strain rate for all deformation temperatures

Temperature and Strain Rate Dependent Anisotropic Plastic Deformation Behavior of AZ31B Mg Alloy

723-729In the present study, the plastic deformation of commercially available AZ31B alloy at different temperatures (300K-473K) and strain rates (0.1s-1-0.01s-1-0.001s-1) under uniaxial tensile test has been carried out. Three different sheet orientations, viz., rolling direction (RD), transverse direction (TD), and 45° to rolling direction have been used. The outcomes of the experiments have demonstrated a temperature-dependent relationship between mechanical properties such as yield strength, ultimate tensile strength, and percentage elongation. The yield strength and ultimate tensile strength has decreased by 28.58% and 31.03% respectively as temperature increased from 300 K to 473 K. At elevated temperature (473 K) the material has exhibited highest ductility (64.88%) as compare to 300 K. The hardening exponent has been found to decrease with increasing temperature. The flow stress behaviour has been predicted using work hardening models such as the Hollomon and Ludwik. Two-stage work hardening behavior has been observed at all the temperatures. According to statistical parameter comparison, Ludwik equation prediction capability of correlation coefficient (0.9959) has been found to be best in agreement with the experimental results