Effect of Y2O3 on high temperature thermal compression performance of Cu-10W composites and microstructure analysis

In this study, Cu-10W and 2 wt%Y2O3/Cu-10W composites were successfully prepared via mechanical ball milling and spark plasma sintering. Hot compression experiments on the two materials were carried out in the temperature range of 300 degrees C-600 degrees C and in the strain rate range of 0.01 s(-1)-10 s(-1). The hot deformation activation energy of the two materials was calculated and a constitutive equation was established. The optimum hot deformation process parameters were obtained according to a hot processing map. The effects of Y2O3 on the thermal deformation behavior of the Cu-10W composites and their microstructures were investigated, and the results showed that Y2O3 could enhance the stability of Cu-10W at high temperatures. The activation energies of thermal deformation of Cu-10W and 2 wt%Y2O3/Cu-10W were 159.56 kJ/mol and 129.85 kJ/mol, respectively. Moreover, Y2O3 improved the interfacial bonding strength of Cu and W in the Cu-10W material, effectively preventing the generation of microcracks and pores during the high-temperature compression process; Y2O3 provides more nucleation sites in the recrystallization process, which is favorable for the excitation of recrystallization. A low strain rate at high temperatures favors the occurrence of recrystallization, and the 2 wt%Y2O3/Cu-10W composites tend to exhibit discontinuous dynamic recrystallization (DDRX) under high-Z-value conditions and continuous dynamic recrystallization (CDRX) under low-Z-value conditions.