Time–temperature–transformation diagram and microstructures of bulk glass forming Pd40Cu30Ni10P20

摘要: Isothermal crystallization studies were performed on the bulk glass forming alloy Pd40Cu30Ni10P20 in undercooled liquid region between transition and liquidus temperature, resulting a complete time–temperature–transformation (TTT) diagram for crystallization. The TTT shows typical "C" shape with nose at 50 s 680 K. Assuming steady state nucleation diffusion-controlled growth rate, was successfully fit over entire range of measurement. microstructure after isothermal modulation Cu P all degrees undercooling. primary solidified phase is Cu3Pd, which forms distinct dendrites low From additional constant cooling experiments, critical rate to bypass determined be 0.33 K/s.