Using scanning tunneling microscopy (STM) and first-principles local-spin-density-approximation calculations to study submonolayer films of Co (1-c)Ag (c)/Ru(0001) alloys, we have discovered a novel phase-separation mechanism. When the Ag concentration c exceeds 0.4, the surface phase separates between a dislocated, pure Ag phase and a pseudomorphically strained Co(0.6)Ag (0.4) surface alloy. W...

We describe the synthesis, magnetism and structure of CoPtCrB alloys with Pt concentrations from 10 43 %. The Cr concentration in the alloys was 15-17 % and the B concentration was 9-11 %. The magnetic anisotropy and coercivity increase with increasing Pt up to M 30%, plateau at M 35,000 Oe and w 6000 Oe, respectively, and then decrease. Transmission electron microscopy results show the media f...

In this study, Cu50-Ni50 alloy were synthesized by mechanical alloying. The alloy was then reinforced by dispersion of multiwalled carbon nanotubes using a planetary high energy ball mill. X-ray diffraction, scanning electron microscopy and vibrating sample magnetometer were used to evaluate the effects of CNT addition on the characteristics of the nanocomposites. XRD results of Cu-Ni sample sh...

The nucleation rate depends on the free-energy barrier and the kinetic factor. While the role of the free energy barrier is a text-book subject, the importance of the kinetic factor is frequently underestimated. In this study, we applied the mean first-passage time method, to obtain the free-energy landscape and kinetic factor directly from the molecular dynamics (MD) simulations of the nucleat...

Previously, high temperature properties of the silver-palladium-copper-gold alloy were investigated. In this study, the thermal expansion percentage and coefficient, and high temperature strengths of ADAS Type 3 gold alloy were investigated up to the liquidus temperature. Furthermore, microstructural and compositional changes in the solid/liquid dual phase were studied. The following conclusion...

Duplex stainless steels are desirable for use in power generation systems because of their attractive combination of strength, corrosion resistance and cost. However, thermal embrittlement at intermediate homologous temperatures of 475 C and below, limits upper service temperatures for many applications. New lean grade duplex alloys have improved thermal stability over standard grades and poten...

By means of detailed electronic structure calculations, we show that strained HgTe(x)S(1-x) alloys show a surprisingly rich topological phase diagram. In the strong topological insulator phase, the spin chirality of the topological nontrivial surface states can be reversed by adjusting the alloy concentration x and the strain. On top of this, we predict two semimetallic topological phases, name...

The microstructures of ¡-Mg, long-period stacking ordered (LPSO) phases, and kink bands in a Mg­Y­Zn alloy were observed by transmission electron microscopy (TEM). The results showed that extruded Mg97Zn1Y2 alloy included different kinds of phases: 2H-Mg, 2H-Mg with many stacking faults, 14H and 18R. Kink bands tended to occur in areas where there were many intermetallic compounds. The element ...

Novel Ti6Al4V alloy matrix composites with a controllable two-scale network architecture were successfully fabricated by reaction hot pressing (RHP). TiB whiskers (TiBw) were in-situ synthesized around the Ti6Al4V matrix particles, and formed the first-scale network structure (FSNS). Ti5Si3 needles (Ti5Si3) precipitated in the β phase around the equiaxed α phase, and formed the secondary-scale ...