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Title: Characterization of the protective surface films formed on molten magnesium in air/HFC-134a atmospheres

Abstract

The surface films formed on molten magnesium in an air/HFC-134a gas mixture at 700 deg. C were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and Auger electron spectroscopy (AES). The results showed that there was a protective film on molten magnesium surface, which can prevent molten magnesium from oxidation and ignition. The surface film contained primarily four elements: magnesium, fluorine, oxygen and carbon, and was composed of MgF{sub 2}, MgO and C. The film properties depended on the HFC-134a concentration in the gaseous mixture and exposure time. The thickness of the film formed after exposure to air containing 0.5% HFC-134a for 10 min was about 1-2 {mu}m.

Authors:
 [1];  [2];  [2]
  1. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Shaanxi, Xi'an 710072 (China) and Department of Chemistry and Chemical Engineering, Baoji College of Arts and Science, Shaanxi, Baoji 721007 (China). E-mail: chk@mail.nwpu.edu.cn
  2. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Shaanxi, Xi'an 710072 (China)
Publication Date:
OSTI Identifier:
21003521
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 58; Journal Issue: 1; Other Information: DOI: 10.1016/j.matchar.2006.03.012; PII: S1044-5803(06)00093-3; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AIR; AUGER ELECTRON SPECTROSCOPY; FILMS; FLUORINE; HAFNIUM CARBIDES; IGNITION; MAGNESIUM; MAGNESIUM FLUORIDES; MAGNESIUM OXIDES; MICROSTRUCTURE; OXIDATION; SCANNING ELECTRON MICROSCOPY; THICKNESS; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Chen Hukui, Liu Jianrui, and Huang Weidong. Characterization of the protective surface films formed on molten magnesium in air/HFC-134a atmospheres. United States: N. p., 2007. Web. doi:10.1016/j.matchar.2006.03.012.
Chen Hukui, Liu Jianrui, & Huang Weidong. Characterization of the protective surface films formed on molten magnesium in air/HFC-134a atmospheres. United States. doi:10.1016/j.matchar.2006.03.012.
Chen Hukui, Liu Jianrui, and Huang Weidong. Mon . "Characterization of the protective surface films formed on molten magnesium in air/HFC-134a atmospheres". United States. doi:10.1016/j.matchar.2006.03.012.
@article{osti_21003521,
title = {Characterization of the protective surface films formed on molten magnesium in air/HFC-134a atmospheres},
author = {Chen Hukui and Liu Jianrui and Huang Weidong},
abstractNote = {The surface films formed on molten magnesium in an air/HFC-134a gas mixture at 700 deg. C were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and Auger electron spectroscopy (AES). The results showed that there was a protective film on molten magnesium surface, which can prevent molten magnesium from oxidation and ignition. The surface film contained primarily four elements: magnesium, fluorine, oxygen and carbon, and was composed of MgF{sub 2}, MgO and C. The film properties depended on the HFC-134a concentration in the gaseous mixture and exposure time. The thickness of the film formed after exposure to air containing 0.5% HFC-134a for 10 min was about 1-2 {mu}m.},
doi = {10.1016/j.matchar.2006.03.012},
journal = {Materials Characterization},
number = 1,
volume = 58,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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