The as-forged Ti3Al-based alloy and TC11 titanium alloy were welded by electron beams in vacuum, and then they were processed using near isothermal forging and gradient heat treatment. The experimental results show th...The as-forged Ti3Al-based alloy and TC11 titanium alloy were welded by electron beams in vacuum, and then they were processed using near isothermal forging and gradient heat treatment. The experimental results show that the near isothermal forging processing parameters have little effect on the phase constitution of the weld. The weld consists of Ti2AlNb, MoNb, Nb3Al, and TiAl3 phases as well as the two main phases of α and α2. However, the near isothermal forging processing parameters have significant effect on the shape, size, and volume fraction of α and α2 phases of the welding interface. The sizes of the α and α2 phases increase as the strain rate decreases. Because the distortion energy of the lattice and the volume fraction of the grains occurring in dynamic recrystallization increase with an increase in deformation, the sizes of the α and α2 phases of the welding interface decrease.展开更多
The dynamic evolution of microstructure and the characteristics of deformation , as well as the relationshipbetween them have ben studied for TCll alloy with different original conditions, including as-cast, as-rolled...The dynamic evolution of microstructure and the characteristics of deformation , as well as the relationshipbetween them have ben studied for TCll alloy with different original conditions, including as-cast, as-rolled ,as-forged and as-predeformed on casting, during comparison at constant temperature (CCT). The resultsshow that (1) Micrcotructural process during CCT of cast TCll comprises two stages: (i) Founding ofu dynamic equilibrium ”. Original coarse structure breaks up and becomes equiaxed, while the stras decreasesaccordingly. The microstructure gradually trends towards some kind of “dynamic ellullibrium” morphology;(ii) Keeping of “dynamic equilibrium”. Both stress and micrcostructural morphology preserve stable althoughdeformation continues. (2) The final pouilibrium morphology das not depend on its initial microstructure, buton the parameter Z(T, e) .展开更多
基金supported by the Natural Na-tional Science Foundation of China (No. 50775187)
文摘The as-forged Ti3Al-based alloy and TC11 titanium alloy were welded by electron beams in vacuum, and then they were processed using near isothermal forging and gradient heat treatment. The experimental results show that the near isothermal forging processing parameters have little effect on the phase constitution of the weld. The weld consists of Ti2AlNb, MoNb, Nb3Al, and TiAl3 phases as well as the two main phases of α and α2. However, the near isothermal forging processing parameters have significant effect on the shape, size, and volume fraction of α and α2 phases of the welding interface. The sizes of the α and α2 phases increase as the strain rate decreases. Because the distortion energy of the lattice and the volume fraction of the grains occurring in dynamic recrystallization increase with an increase in deformation, the sizes of the α and α2 phases of the welding interface decrease.
文摘The dynamic evolution of microstructure and the characteristics of deformation , as well as the relationshipbetween them have ben studied for TCll alloy with different original conditions, including as-cast, as-rolled ,as-forged and as-predeformed on casting, during comparison at constant temperature (CCT). The resultsshow that (1) Micrcotructural process during CCT of cast TCll comprises two stages: (i) Founding ofu dynamic equilibrium ”. Original coarse structure breaks up and becomes equiaxed, while the stras decreasesaccordingly. The microstructure gradually trends towards some kind of “dynamic ellullibrium” morphology;(ii) Keeping of “dynamic equilibrium”. Both stress and micrcostructural morphology preserve stable althoughdeformation continues. (2) The final pouilibrium morphology das not depend on its initial microstructure, buton the parameter Z(T, e) .
