Theoretical calculation of nucleation temperature and the undercooling behaviors of Fe-Cr alloys studied with the electromagnetic levitation method

Journal Article · Thu Jul 01 04:00:00 EDT 1999 · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science

DOI:https://doi.org/10.1007/s11661-999-0181-y· OSTI ID:677990

Zhang, X; Tsukamoto, Susumu ^[1]

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1. National Research Inst. of Metals, Tsukuba, Ibaraki (Japan). Joining and Interface Research Station

The nucleation temperature of Fe-Cr alloys was calculated according to the classical nucleation theory with a general solution model for the bulk free energy change in crystal nucleation in binary melts and recent models for the solid-liquid interface energy. The results were compared with each other and with the maximum undercooling results obtained in the electromagnetic levitation experiments. It was found that the general solution free energy change model combined with the Spaepen and Meyer interface energy model can explain the results on the basis of heterogeneous nucleation with the same type of catalytic nucleation sites with a contact angle of about 86 deg. This model using the actual entropy of fusion of the alloys produces the best agreement with the experimental results. Possible factors causing the heterogeneous nucleation were discussed. The cooling rate and catalytic surface area per unit volume were shown to have only a slight effect on the nucleation temperature under the experimental conditions, while the contact angle was found to affect the nucleation temperature very strongly from about 10 to 130 deg.

• Sponsoring Organization: USDOE
• OSTI ID: 677990
• Journal Information: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Journal Name: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science Journal Issue: 7 Vol. 30; ISSN MMTAEB; ISSN 1073-5623
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHROMIUM ALLOYS
CORRELATIONS
INTERFACES
IRON ALLOYS
LEVITATION
LIQUID METALS
MATHEMATICAL MODELS
NUCLEATION
SOLIDIFICATION
TEMPERATURE DEPENDENCE