The role of amorphous precursor in phase selection hierarchy in marginal metallic glasses

OTT, R. T.
Kalay, Yunus Eren
The solid state amorphous structure and devitrification products of Al90Tb10 alloys produced by Cu block meltspinning and magnetron sputtering were investigated by a combined study of differential scanning calorimetry, in-situ X-ray diffraction and conventional transmission electron microscopy. The as-prepared specimens were found to be fully amorphous according to the electron and X-ray diffraction. The thermal analysis and in-situ XRD analyses of the amorphous samples having the same chemistry but different processing history showed clear differences in the devitrification pathways in terms of nanocrystal population, size and the phase selection. The variations in the crystallization path were explained on the basis of distinct topological and chemical medium range ordering observed in as-quenched and as-sputtered amorphous structures.


Effect of Sm on thermal and mechanical properties of Cu-Zr-Al bulk metallic glasses
Sikan, Fatih; Atabay, S. E.; Motallebzadeh, A.; Özerinç, Sezer; Kalay, I.; Kalay, Yunus Eren (Elsevier BV, 2019-01-16)
The effect of rare-earth (Sm) microalloying on the thermal stability and phase selection along with the effect of nanocrystallization on the mechanical properties of amorphous melt-spun ribbons of Zr50Cu40Al10, Zr49Cu39.2Al9.8Sm2 and Zr48Cu38.4Al9.6Sm4 alloys were investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy (TEM), Vickers and nanoindentation hardness tests and micropillar compression analysis. XRD and TEM analyses showed that all samp...
A study of phase stability and mechanical properties of hydroxylapatite-nanosize alpha-alumina composites
Evis, Zafer (Elsevier BV, 2007-04-01)
Hydroxylapatite (HA)-nanosize alumina composites were synthesized to study their phase stability and mechanical properties. To make these composites, nanosize alpha-Al2O3 powder was used because of its better sinterability and densification as compared to nanosize gamma-Al2O3. The composites were air sintered without pressure and hot pressed in vacuum at 1100 degrees C and 1200 degrees C. In the composites, HA decomposed to tricalcium phosphate faster after the air sintering than hot pressing. Moreover, hex...
The quantum confined Stark effect in silicon nanocrystals
Kulakci, Mustafa; SERİNCAN, UĞUR; Turan, Raşit; Finstad, Terje G. (IOP Publishing, 2008-11-12)
The quantum confined Stark effect (QCSE) in Si nanocrystals embedded in a SiO(2) matrix is demonstrated by photoluminescence (PL) spectroscopy at room and cryogenic temperatures. It is shown that the PL peak position shifts to higher wavelengths with increasing applied electric field, which is expected from carrier polarization within the quantum dots. It is observed that the effect is more pronounced at lower temperatures due to the improved carrier localization at the lowest energy states of the quantum d...
The investigation of electronic, anisotropic elastic and lattice dynamical properties of MAB phase nanolaminated ternary borides: M 2 AlB 2 ( M = Mn , Fe and Co ) under spin effects
Surucu, Gokhan; YILDIZ, BUĞRA; Erkisi, Aytac; Wang, Xiaotian; Surucu, Ozge (Elsevier BV, 2020-10-01)
In the present study, the structural, electronic, magnetic, anisotropic elastic and lattice dynamic properties of the ternary metal borides (, and ) known as MAB phases have been investigated by density functional theory. The obtained results from the structural optimizations show that all these compounds have negative formation enthalpy implying the thermodynamic stability and synthesizability. The spin effects on the phases have been studied with the plotted energy-volume curves for different magnetic pha...
Effect of Microstructure on the Mechanical Behavior of Reactive Magnetron Sputtered Al2O3/TiO2 Multilayer Ceramics
Dericioğlu, Arcan Fehmi (Japan Institute of Metals, 2008-11-01)
Mechanical characteristics of reactive magnetron sputtered Al2O3-TiO2 multilayer ceramics were studied. Tailored mechanical properties such as moderately high hardness and reasonable toughness were achieved through varying sputtering process parameters resulting in microstructural control at nano-scale. Interchanging Al2O3 and TiO2 layers with a single layer thickness of similar to 65-70 nm were deposited on single crystal alumina (sapphire) substrates to form the multilayer structure composed of 10 layers....
Citation Formats
C. YILDIRIM, M. KUTSAL, R. T. OTT, M. F. BESSER, M. J. KRAMER, and Y. E. Kalay, “The role of amorphous precursor in phase selection hierarchy in marginal metallic glasses,” MATERIALS & DESIGN, pp. 479–484, 2016, Accessed: 00, 2020. [Online]. Available: