Non-isothermal Crystallization Kinetics of Mold Fluxes for Casting High-Aluminum Steels

Journal Article · Fri Dec 15 04:00:00 EST 2017 · Metallurgical and Materials Transactions B, Process Metallurgy and Materials Processing Science

DOI:https://doi.org/10.1007/S11663-017-1117-3· OSTI ID:22856053

Zhou, Lejun; Li, Huan; Wang, Wanlin; Wu, Zhaoyang; Yu, Jie; Xie, Senlin ^[1]

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1. Central South University, School of Metallurgy and Environment (China)

This paper investigates the crystallization behavior of CaO-SiO{sub 2}- and CaO-Al{sub 2}O{sub 3}-based mold fluxes for casting high-aluminum steels using single hot thermocouple technology, developed kinetic models, and scanning electron microscope. The results showed that the crystallization ability of the typical CaO-SiO{sub 2}-based Flux A (CaO/SiO{sub 2} 0.62, Al{sub 2}O{sub 3} 2 mass pct) is weaker than that of CaO-Al{sub 2}O{sub 3}-based Flux B (CaO/SiO{sub 2} 4.11, Al{sub 2}O{sub 3} 31.9 mass pct) because of its higher initial crystallization temperature. The crystallization kinetics of Flux A was “surface nucleation and growth, interface reaction control” in the overall non-isothermal crystallization process, whereas that of Flux B was “constant nucleation rate, 1-dimensional growth, diffusion control, in the primary crystallization stage, and then transformed into constant nucleation rate, 3-dimensional growth, interface reaction control in the secondary crystallization stage.” The energy dispersive spectroscopy results for Flux B suggested that the variations in the crystallization kinetics for Flux B are due to different crystals precipitating in the primary (BaCa{sub 2}Al{sub 8}O{sub 15}) and secondary (CaAl{sub 2}O{sub 4}) crystallization periods during the non-isothermal crystallization process.

• OSTI ID: 22856053
• Journal Information: Metallurgical and Materials Transactions B, Process Metallurgy and Materials Processing Science, Journal Name: Metallurgical and Materials Transactions B, Process Metallurgy and Materials Processing Science Journal Issue: 6 Vol. 48; ISSN 1073-5615; ISSN MTBSEO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM
ALUMINIUM OXIDES
CALCIUM OXIDES
CASTING
CRYSTAL GROWTH
CRYSTALLIZATION
CRYSTALS
DIFFUSION
NUCLEATION
PRECIPITATION
SCANNING ELECTRON MICROSCOPY
SILICON OXIDES
SPECTROSCOPY
STEELS
THERMOCOUPLES
THREE-DIMENSIONAL LATTICES