Hot compression behaviors and microstructural evolution of beryllium by vacuum hot pressing

Abstract The uniaxial compressive (UAC) performance of beryllium by vacuum hot pressing (VHP) was investigated in the temperature range from 250 to 550 °C and strain rate from 0.01 to 10 s-1. Serrated flow and yield point showed in the stress-strain curve are caused by Portevin-Le Chatelier effect (PLCE). Arrhenius type constitutive equation based on true strain is established and the volume diffusion of Fe and C in solution is deduced by the calculated activation energy. The typical microstructure instability characters are interfacial cracking and intragranular cracking. The optimum deformation parameter is 350℃ and 0.01 s-1, with uniform deformed microstructure and almost little defect increasing.