Investigation of solidification and crystallization of iron based bulk amorphous alloys

Erdiller, Emrah Salim
The aim of this study is to form a theoretical model for simulation of glass forming ability of Fe ? Based bulk amorphous alloys, to synthesize Fe ? based multicomponent glassy alloys by using the predictions of the theoretical study, and to analyze the influence of crystallization and solidification kinetics on the microstructural features of this amorphous alloys. For this purpose, first, glass forming ability of Fe ? (Mo, B, Cr, Nb, C) ? X ( X = various alloying elements, selected from the periodic table) ternary alloy systems were simulated for twenty different alloy compositions by using the electronic theory of alloys in pseudopotential approximation and regular solution theory. Then, by using the results of the theoretical study, systematic casting experiments were performed by using centrifugal casting method. The alloying elements were melted with induction under argon atmosphere in alumina crucibles and casted into copper molds of different shapes. Characterization of the cast specimens were performed by using DSC, XRD, SEM, and optical microscopy. Comparison of equilibrium and nonequilibrium solidification structures of cast specimens were also performed so as to verify the existence of the amorphous phase. Good agreement of the results of experimental work, with the predictions of the theoretical study, and the related literature was obtained.


Molecular dynamics study of random and ordered metals and metal alloys
Kart, Hasan Hüseyin; Tomak, Mehmet; Department of Physics (2004)
The solid, liquid, and solidification properties of Pd, Ag pure metals and especially PdxAg1-x alloys are studied by using the molecular dynamics simulation. The effects of temperature and concentration on the physical properties of PdxÞAg1-x are analyzed. Sutton-Chen (SC) and Quantum Sutton-Chen (Q-SC) many-body potentials are used as interatomic interactions which enable one to investigate the thermodynamic, static, and dynamical properties of transition metals. The simulation results such as cohesive ene...
Synthesis and characterization of Ti-based bulk amorphous/naocrystalline alloys for engineering applications
Abdelal, Ali; Akdeniz, Mahmut Vedat; Department of Metallurgical and Materials Engineering (2004)
Amorphous and bulk amorphous metallic alloys are an intriguing class of structural materials and possess a range of interesting properties, including near theoretical strength, high hardness, extremely low damping characteristics, excellent wear properties, high corrosion resistance, low shrinkage during cooling and almost perfect as-cast surfaces with good potential for forming and shaping. In this study, new Ti-based bulk amorphous alloys are tried to be modeled and synthesized. For that purpose, electron...
Theoretical prediction of bulk glass forming ability (BGFA) of Ti-Cu based multicomponent alloys
SUER, Sila; Mehrabov, Amdulla; Akdeniz, Mahmut Vedat (Elsevier BV, 2009-03-01)
The bulk glass forming ability (BGFA) of Ti-Cu based multicomponent alloys has been evaluated via theoretical modeling and computer simulation studies based on a combination of electronic theory of alloys in the pseudopotential approximation and the statistical thermodynamical theory of liquid alloys The. magnitude of atomic ordering energies, calculated by means of the electronic theory of alloys in the pseudopotential approximation, was subsequently used for calculation of the key thermodynamic parameters...
Investigation of warpage behavior of single crystal silicon on a silicon Adhesive ceramic integrated structure at cryogenic temperatures
Baloğlu, Can; Okutucu Özyurt, Hanife Tuba; Dursunkaya, Zafer (2016-03-17)
Understanding thermal stress and warpage behavior of heterogeneous component assemblies is vital in infrared sensor applications of silicon semiconductor material. The silicon semiconductor warpage behavior of the integrated structure composed of silicon material itself, an adhesive layer and a ceramic layer is analyzed by both FEM and experimental studies. The studies are performed between room temperature and 80 K. Thickness of each layer has an effect on the warpage. The silicon warpage of the initial ba...
Simulation of crystallization and glass formation processes for binary Pd-Ag metal alloys
Kart, HH; Uludogan, M; Cagin, T; Tomak, Mehmet (2003-09-12)
Glass formation and crystallization process of Pd-Ag metallic alloys are investigated by means of molecular dynamics simulation. This simulation uses the quantum Sutton-Chen (Q-SC) potential to study structural and transport properties of Pd-Ag alloys. Cooling rates and concentration effects on the glass formation and crystallization of binary alloys considered in this work are investigated. Pd-Ag alloys show the glass structure at fast cooling rates while it crystallizes at slow cooling rates. Increment of...
Citation Formats
E. S. Erdiller, “Investigation of solidification and crystallization of iron based bulk amorphous alloys,” M.S. - Master of Science, Middle East Technical University, 2004.