In electrochemical energy conversion and storage, existing catalysts often contain a high percentage of noble metals such as Pt and Pd. In order to develop low-cost electrocatalysts, one of the effective strategies involves alloying noble metals with other transition metals. This strategy promises not only significant reduction of noble metals but also the tunability for enhanced catalytic acti...

Activating the plasticity of ZrB2 is a promising approach to improve its key properties for applications in hypersonic vehicles, including high temperature strength and thermal shock resistance. The present work demonstrates that ideal shear strength of ZrB2, which is a good indicator of the critical stress for dislocation nucleation, can be significantly reduced by dissolving of appropriate al...

The development of alloyed quantum dot (QD) nanocrystals with attractive optical properties for a wide array of chemical and biological applications is a growing research field. In this work, size-tunable engineered band gap composition-dependent alloying and fixed-composition alloying were employed to fabricate new L-cysteine-capped alloyed quaternary CdZnTeS QDs exhibiting different internal ...

Molecular dynamics (MD) simulations using a first principles-based Embedded-atom-Method (EAM) potential are used to simulate the exothermic alloying reactions of a NiAl bilayer at 1500 K and 1100 K. Both microcanonical (NVE) and isoenthalpic (NPH) MD simulations are used to demonstrate the influence of pressure on atomic mixing and subsequent alloying reaction. The NVE simulations, in which the...

production of fe-c alloy powders by mechanical alloying was studied. fe and graphite elemental powdermixtures containing 0.8 and 1.5wt.% graphite were mechanically alloyed using a planetary ball mill. thestructural changes of powder particles during mechanical alloying were studied by x-ray diffractometery,scanning electron microscopy and microhardness measurements. for both compositions, mecha...

In this research, the effect of two process control agent: methanol (liquid state) and stearicacid (solid state) on mechanical alloying process of Ti and Al with equal at%(Ti50Al50) wereinvestigated. Phase transformation at presence of two PCA was: at first, powder mixture wastransformed to a metastable solid solution of Al in Ti lattice (disordered hcp) and then transformed toamorphous phase w...

In this work, mechanical alloying was employed to produce Ti-50Al and Ti-45Al-5Cr (at%) alloys. Alloying was performed in a planetary mill and the alloying time varying from 5 to 70h. Characterization of the powder mixture was performed by X-ray diffraction (XRD), SEM analyses and DTA test, during mechanical alloying and after annealing at 1100°c in vacuum oven. The results showed, after 50h of...

The dezincification of brasses has been the subject of substantial conjecture and investigation over the past century and the technical press is littered with papers on the problem. Very broadly the technical literature can be subdivided into five main groups as follows: (a) Observations of dezincification phenomena including mechanically induced dezincification and in-service experience in var...

This paper proposes method for solving steel alloying problem using evolution algorithms SOMA and differential evolution. Both algorithms belong to the family of the evolution algorithms but the main ideas of these algorithms are different. In differential evolution new offspring is created during the evolution, the individuals are crossed and mutated, while in SOMA the individuals move in the ...

Ferrous metals include cast iron, steel, and the various steel alloys, The only difference between iron and steel is the carbon content. Cast iron contains more than 2-percent carbon, while steel contains less than 2 percent. An alloy is a substance composed of two or more elements. Therefore, all steels are an alloy of iron and carbon, but the term “alloy steel” normally refers to a steel that...