| 摘 要： | The morphology and kinetics evolution of γ' and γ phases in Ni-xAl-(20-x)Cr at%(x=7.5-13.7) alloys aged at700℃ were studied by utilizing the phase-field simulation.The separated γ' phases from γ matrix in low Al content(x 13) alloys transferred to the interconnected morphology with separated y phases in high Al content(x 13) alloys,and long-time aging produced near cubic γ' phase.The coarsening rate of γ' phase declined firstly when the Al content x=7.5-9.0,then increased sharply as x ranges from 9 to 12,while the coarsening rate of γphase declined directly.Additionally,the average edge-to-edge distance of neighboring γ' phases showed a threestage variation when Al content x 9,it decreased to minimum value and increased slowly then decreased again with aging time.In contrast,when 9 ≤ x 13,the average particle distance of γ' phase decreased to a nearly constant value.With the coarsening of y phase,their average particle distance increased.The kinetics evolution was clarified with the combined variations of the particle number density,average particle radius and volume fractions in the continuous composition Ni-xAl-(20-x)Cr at% alloys.
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