With microscopic phase-field kinetic model, atomic-scale computer simulation program for the precipitation sequence and microstructure evolution of the ordered intermetallic compound γ' and θ in ternary Ni75AlxV25-...With microscopic phase-field kinetic model, atomic-scale computer simulation program for the precipitation sequence and microstructure evolution of the ordered intermetallic compound γ' and θ in ternary Ni75AlxV25-x alloy were studied. The simulation results show that Al concentration has important effects on the precipitation sequence. When Al concentration in Ni75AlxV25-x alloy is low, 0(Ni3V) ordered phase will be firstly precipitated, followed by γ'(Ni3Al) ordered phase. With Al concentration increasing, θ and γ' ordered phases are simultaneously precipitated. With A1 concentration further increasing, γ' ordered phase is firstly precipitated, followed by θ ordered phase. There is a competition relationship between θ and γ' ordered phases during growth and coarsening process. No matter which first precipitates, θ ordered phase always occupies advantage in the competition process of coarsening, thus, the microstructure with preferred orientation is formed.展开更多
基金Projects(51174168,51274167)supported by the National Natural Science Foundation of ChinaProject(2014JM7261)supported by the Natural Science Basic Research Plan in Shaanxi Province of ChinaProject(B08040)supported by "111" Project,China
文摘With microscopic phase-field kinetic model, atomic-scale computer simulation program for the precipitation sequence and microstructure evolution of the ordered intermetallic compound γ' and θ in ternary Ni75AlxV25-x alloy were studied. The simulation results show that Al concentration has important effects on the precipitation sequence. When Al concentration in Ni75AlxV25-x alloy is low, 0(Ni3V) ordered phase will be firstly precipitated, followed by γ'(Ni3Al) ordered phase. With Al concentration increasing, θ and γ' ordered phases are simultaneously precipitated. With A1 concentration further increasing, γ' ordered phase is firstly precipitated, followed by θ ordered phase. There is a competition relationship between θ and γ' ordered phases during growth and coarsening process. No matter which first precipitates, θ ordered phase always occupies advantage in the competition process of coarsening, thus, the microstructure with preferred orientation is formed.