کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1601964 1005225 2008 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Growth behavior and microstructure of oxide scales grown on WSi2 coating
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فلزات و آلیاژها
پیش نمایش صفحه اول مقاله
Growth behavior and microstructure of oxide scales grown on WSi2 coating
چکیده انگلیسی

Growth behavior and microstructure of oxide scales formed on WSi2 coating by isothermal oxidation between 800 and 1300 °C were investigated. At and below 1000 °C, lamellar WO3 embedded in the amorphous SiO2 matrix was formed from the direct oxidation of WSi2 by inward diffusion of oxygen through short-circuit paths. At the intermediate temperatures between 1100 and 1200 °C, fastest oxidation rate was observed. The oxide scale consisted of the spheroidal WO3 particles embedded in the amorphous SiO2 matrix. WSi2 was initially oxidized to form W5Si3 and SiO2 followed by the oxidation of W5Si3 to form WO3 and SiO2 phases. At 1300 °C, oxide scale consisted of continuous cristobalite SiO2 and W5Si3 layer underneath, leading to the slowest isothermal oxidation behavior. It is concluded that the interplay of phase stability of WSi2, defect formation process, and viscosity of SiO2 gives rise to unique and complex oxidation behavior especially at intermediate temperatures.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Intermetallics - Volume 16, Issue 3, March 2008, Pages 360–372
نویسندگان
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