Processing maps for the Cu-Cr-Zr-Y alloy hot deformation behavior

Abstract

Hot deformation behavior of the Cu-Cr-Zr-Y alloy was studied by hot compressive tests in the 650-850 °C temperature and 0.001-10 s-1 strain rate ranges using the Gleeble-1500D thermo-mechanical simulator. The flow stress behavior and microstructure evolution were observed during the hot deformation process. The peak stress increases with decreasing temperature and increasing strain rate. The apparent activation energy for hot deformation of the alloy is 336 kJ/mol. Based on the dynamic material model, the processing maps for the alloy were obtained at 0.3, 0.4 and 0.5 strain. The evolution of dynamic recrystallization microstructure strongly depends on the deformation temperature and strain rate. Dynamic recovery is the main softening mechanism at low temperature and high strain rate. Dynamic recrystallization appears at high temperatures and low strain rates. The precipitates of chromium-rich particles were observed during hot deformation. The addition of Y can refine the grain and effectively improve the hot workability of the Cu-Cr-Zr alloy. According to the processing maps and microstructure observations, the optimal hot working parameters for the Cu-Cr-Zr-Y alloy are 800-850 °C temperature range and 0.01-1 s-1 strain rate range.

A new dynamic recrystallization kinetics model for a Nb containing Ni-Fe-Cr-base superalloy considering influences of initial δ phase

“…The diffusion and migration of atom are enhanced by high deformation temperature, further leading to the augment of grain boundary mobility [57]. Then, the nucleation and growth of DRX grain occur.…”

Small Y Addition Effects on Hot Deformation Behavior of Copper‐Matrix Alloys

“…After deformation, the samples were immediately quenched in water to retain the thermoplastic deformation microstructure. [27] Furthermore, dislocation tangle was eliminated in the Cu-Zr-Y alloy. An OLYMPUS PMG3 optical microscope was used to observe microstructure evolution, and the solution structures for Cu-Zr and Cu-Zr-Y alloys are shown in Figure 1b and c. Metallographic samples were prepared by polishing and etching with a solution containing HCl þ C 2 H 5 OH þ FeCl 3 .…”

“…Finally, the samples were prepared by ion milling in a Gatan 691 ion beam thinner. [27] 3.2. It can be clearly seen that the stress, strain, and deformation temperature are related.…”

Hot Deformation Behavior and Processing Maps of a Medium Manganese TRIP Steel

“…Constitutive equations are generally used to calculate and analyze the activation and the relationship among deformation temperature, flow stress and strain. Zener-Hollomon equation can characterize the effect of deformation temperature and strain rate, especially at high-deformation temperature, on the deformation process [30][31][32]. The corresponding equations are as followed:…”

“…However, Lin and Chen [17] reviewed the constitutive equations and found that the flow stress equations in Refs. [32,33] did not consider the effect of strain. Therefore, they established a modified model that compensated for strain and strain rate and considered Q, n, A and a as a polynomial function of strain [36].…”