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Abnormal correlation between phase transformation and cooling rate for pure metals.

ABSTRACT: This work aims to achieve deep insight into the phenomenon of phase transformation upon rapid cooling in metal systems and reveal the physical meaning of scatter in the time taken to reach crystallization. The total number of pure metals considered in this work accounts for 14. Taking pure copper as an example, the correlation between phase selection of crystal or glass and cooling rate was investigated using molecular dynamic simulations. The obtained results demonstrate that there exists a cooling rate region of 6.3?×?10(11)-16.6?×?10(11)?K/s, in which crystalline fractions largely fluctuate along with cooling rates. Glass transformation in this cooling rate region is determined by atomic structure fluctuation, which is controlled by thermodynamic factors. According to the feature of bond-orientation order at different cooling rates, we propose two mechanisms of glass formation: (i) kinetic retardation of atom rearrangement or structural relaxation at a high cooling rate; and (ii) competition of icosahedral order against crystal order near the critical cooling rate.

SUBMITTER: Han JJ

PROVIDER: S-EPMC4778031 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Abnormal correlation between phase transformation and cooling rate for pure metals.

Han J J JJ Wang C P CP Liu X J XJ Wang Y Y Liu Z-K ZK Zhang T-Y TY Jiang J Z JZ

Scientific reports 20160304

This work aims to achieve deep insight into the phenomenon of phase transformation upon rapid cooling in metal systems and reveal the physical meaning of scatter in the time taken to reach crystallization. The total number of pure metals considered in this work accounts for 14. Taking pure copper as an example, the correlation between phase selection of crystal or glass and cooling rate was investigated using molecular dynamic simulations. The obtained results demonstrate that there exists a coo ...[more]

PMID: 26939584

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Abnormal correlation between phase transformation and cooling rate for pure metals.

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Abnormal correlation between phase transformation and cooling rate for pure metals.

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