Coupling of homogeneous and heterogeneous melting kinetics in polycrystalline materials

Meizhen Xiang; Yi Liao; Guomeng Li; Jun Chen

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arXiv · 1904.07397

Coupling of homogeneous and heterogeneous melting kinetics in polycrystalline materials

Meizhen Xiang·Yi Liao·Guomeng Li·Jun Chen

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Abstract

Melting kinetics of polycrystalline materials is analyzed on the basis of a new model which explicitly couples homogeneous and heterogeneous melting mechanisms. The distinct feature of this approach lies in its ability to evaluate not only grain-size-distribution effects on the overall melting kinetics but also competitions between the two melting mechanisms. For the first time, we reveal the three-part structure of temperature-time-transformation diagrams for melting of polycrystalline materials, through which it is possible to determine a critical temperature across which the dominant melting mechanism switches. The critical temperature increases as the mean-grain-diameter decreases following a negative power-law. The results are qualitatively consistent with experimental observations.

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Meizhen Xiang, Yi Liao, Guomeng Li, Jun Chen. 2019-04-16. Coupling of homogeneous and heterogeneous melting kinetics in polycrystalline materials. https://arxiv.org/abs/1904.07397

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