tailieunhanh - LUẬN VĂN " A THESIS SUBMITTED TO THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES OF MIDDLE EAST TECHNICAL UNIVERSITY "

The aim of the study was to investigate the crystallization kinetics and solidification behaviour of Fe60Co8Mo5Zr10W2B15 bulk glass forming alloy. The solidification behaviour in near-equilibrium and non-equilibrium cooling conditions was studied. The eutectic and peritectic reactions were found to exist in the solidification sequence of the alloy. The bulk metallic glass formation was achieved by using two methods: quenching from the liquid state and quenching from the semi-state. Scanning electron microscopy, x-ray diffraction and thermal analysis techniques were utilized in the characterization of the samples produced throughout the study. The choice of the starting material and the alloy preparation method was found to be effective in the amorphous phase. | SOLIDIFICATION AND CRYSTALLIZATION BEHAVIOUR OF BULK GLASS FORMING ALLOYS A THESIS SUBMITTED TO THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES OF MIDDLE EAST TECHNICAL UNIVERSITY BY SULTAN AYBAR IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN METALLURGICAL AND MATERIALS ENGINEERING SEPTEMBER 2007 Approval of the thesis SOLIDIFICATION AND CRYSTALLIZATION BEHAVIOUR OF BULK GLASS FORMING ALLOYS submitted by Sultan AYBAR in partial fulfillment of the requirements for the degree of Master of Science in Metallurgical and Materials Engineering Department Middle East Technical University by Prof. Dr. Canan Ozgen ------------- Dean Graduate School of Natural and Applied Sciences Prof. Dr. Tayfur Ozturk ------------- Head of Department Metallurgical and Materials Engineering Prof. Dr. M. Vedat Akdeniz ------------- Supervisor Metallurgical and Materials Eng. Dept. METU Prof. Dr. Amdulla O. Mekhrabov Co-supervisor Metallurgical and Materials Eng. Dept. METU Examining Committee Members Prof. Dr. Tayfur Ozturk ------------------------ Metallurgical and Materials Eng. Dept. METU Prof. Dr. M. Vedat Akdeniz Metallurgical and Materials Eng. Dept. METU Prof. Dr. Amdulla O. Mekhrabov Metallurgical and Materials Eng. Dept. METU Prof. Dr. ishak Karakaya ------------------------ Metallurgical and Materials Eng. Dept. METU Asst. . Kazim TUR Materials Eng. Dept. Atilim University Date -------------------------- I hereby declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that as required by these rules and conduct I have fully cited and referenced all material and results that are not original to this work. Name Last name Sultan Aybar Signature .