With the multi-phase field model, the unidirectional solidification with constant velocity growth and variable velocity growth of the CBr4-C2C16 eutectic alloy is simulated in three dimensions. The simulated results w...With the multi-phase field model, the unidirectional solidification with constant velocity growth and variable velocity growth of the CBr4-C2C16 eutectic alloy is simulated in three dimensions. The simulated results with constant velocity growth show that with the increase of pulling velocity, the morphology of the CBr4-C2C16 alloy evolves in the sequence of lamellar merging -lamellar-rod transition-stable lamellar growth-oscillating growth-lamellar branching. A morphology selection map is established with different pulling velocities, which is confirmed to be correct by the velocity change process. It is shown that all of the morphology transitions, the average interface growth velocity and average interface undercooling show a hysteresis effect against the instant of velocity change. The relationship between the interface average undercooling and interface average growth velocity is consistent with the theoretical value.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 51001082)the China Postdoctoral Science Foundation (Grant No. 20090460654)Shanghai Science and Technology Commit-tee (Grant Nos. 0752nm004 and 08DZ2201300)
文摘With the multi-phase field model, the unidirectional solidification with constant velocity growth and variable velocity growth of the CBr4-C2C16 eutectic alloy is simulated in three dimensions. The simulated results with constant velocity growth show that with the increase of pulling velocity, the morphology of the CBr4-C2C16 alloy evolves in the sequence of lamellar merging -lamellar-rod transition-stable lamellar growth-oscillating growth-lamellar branching. A morphology selection map is established with different pulling velocities, which is confirmed to be correct by the velocity change process. It is shown that all of the morphology transitions, the average interface growth velocity and average interface undercooling show a hysteresis effect against the instant of velocity change. The relationship between the interface average undercooling and interface average growth velocity is consistent with the theoretical value.
