Coupling phase field with creep damage to study γ’ evolution and creep deformation of single crystal superalloys
来源期刊：JOURNAL OF MATERIALS SCIENCE TECHNOLOG2021年第12期
论文作者：Min Yang Jun Zhang Weimin Gui Songsong Hu Zhuoran Li Min Guo Haijun Su Lin Liu
摘 要：A phase-field model coupling with elastoplastic de fo rmation and creep damage has been built to study the micro structural evolution and deformation behavior for Ni-Al single crystal alloy during the whole creep processing.The relevant experiments were conducted to verify the model validity.The simulation re sults show that under the tensile creep at 1223 K/100 MPa,cubic γ’ phases coarsen along the direction parallel to the axis of tensile stress during the first two creep stages;and spindle-shaped and wavy γ’ phases are fo rmed during tertiary creep,similar to the experimental results.The evolution mechanism of γ’ phases is analyzed from the perspective of changes of stress and strain fields.The "is land-like" γ phase is observed and its formation mechanism is discussed.With the increase of creep stress,the directional coarsening of γ’ phase is accelerated,the steady-state creep rate is increased and the creep life is decreased.The comparison between simulated and experimental creep curves shows that this phase-field model can effectively simulate the performance changes during the first two creep stages and predict the influence of creep stresses on creep properties.Our work provides a potential approach to synchronously simulate the creep microstructure and property of superalloys strengthened by γ’ precipitates.
Min Yang1，Jun Zhang1，Weimin Gui2，Songsong Hu1，Zhuoran Li1，Min Guo1，Haijun Su1，Lin Liu1
1. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University2. Shaanxi Fast Gear Co., Ltd.
摘 要：A phase-field model coupling with elastoplastic de fo rmation and creep damage has been built to study the micro structural evolution and deformation behavior for Ni-Al single crystal alloy during the whole creep processing.The relevant experiments were conducted to verify the model validity.The simulation re sults show that under the tensile creep at 1223 K/100 MPa,cubic γ’ phases coarsen along the direction parallel to the axis of tensile stress during the first two creep stages;and spindle-shaped and wavy γ’ phases are fo rmed during tertiary creep,similar to the experimental results.The evolution mechanism of γ’ phases is analyzed from the perspective of changes of stress and strain fields.The "is land-like" γ phase is observed and its formation mechanism is discussed.With the increase of creep stress,the directional coarsening of γ’ phase is accelerated,the steady-state creep rate is increased and the creep life is decreased.The comparison between simulated and experimental creep curves shows that this phase-field model can effectively simulate the performance changes during the first two creep stages and predict the influence of creep stresses on creep properties.Our work provides a potential approach to synchronously simulate the creep microstructure and property of superalloys strengthened by γ’ precipitates.
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