We have investigated the vibrational anharmonicity and quantum effects in the Invar alloy Fe64.6Ni35.4 which shows anomalously small thermal expansion. We have performed Fe and Ni K-edge EXAFS spectroscopic measurements and computational simulations based on the path-integral effective-classical-potential theory. The first nearest-neighbor (NN) shells around Fe showed almost no thermal expansio...

An elemental powder sintering (EPS) technique has been developed for the synthesis of porous NiTi alloy, in which Ni and Ti powders are used as the reactants and TiH2 powder is added as a pore-forming agent and active agent. Effects of various experimental parameters (sintering temperature, sintering time, and TiH2 content) on the porosity, pore size and pore distribution as well as phase compo...

Pt(3)Ni alloy nanoparticle networks (Pt(3)Ni NN) were prepared through a simple one-step room-temperature synthetic method. The as-prepared Pt(3)Ni NN exhibited markedly improved activity for both oxygen reduction reaction and electrocatalytic oxidation of small organic molecules over the Pt nanoparticle networks (Pt NN) and commercially available Pt/C.

OBJECTIVE The aims of the study are to assess the marginal accuracy of base metal and titanium alloy casting and to evaluate the effect of repeated ceramic firing on the marginal accuracy of base metal and titanium alloy castings. MATERIALS AND METHODS Twenty metal copings were fabricated with each casting material. Specimens were divided into 4 groups of 10 each representing base metal alloy...

Successful development of metallic filters with high temperature oxidation/corrosion resistance for fly ash capture is a key to enabling advanced coal combustion and power generation technologies. Compared to ceramic filters, metallic filters can offer increased resistance to impact and thermal fatigue, greatly improving filter reliability. A beneficial metallic filter structure, composed of a ...

The superelastic behavior of coil springs of a Ti-Ni shape memory alloy was investigated using loading-unloading cycling tests under isothemal temperatures. The effects of the Ni content and shape memory treatment temperatures on the cyclic behavior in the superelastic deformation were investigated. The deformation behavior within the elastic region of the parent phase scarcely changes during t...

Plasma Transferred Arc hardfacing (PTA) is an excellent tool for surface tailoring as it allows for the manipulation of coatings chemical composition. In particular in-situ alloy development can be achieved during the deposition of different powder mixtures. In this work powder mixtures of Ni-Al, Nb-Al and Fe-Al were deposited by PTA. Coatings were characterized for their mechanical features at...

Three different Ti-based alloys with bcc structure and Laves phase were studied. The TiCr 1.1 V 0.9 , TiCr 1.1 V 0.45 Nb 0.45 and TiCr 1.1 V 0.9 + 4%Zr 7 Ni 10 alloys were melted in arc furnace under argon atmosphere. The hydrogen absorption capacity was measured by using aparatus type Sievert’s. Crystal structures, and the lattice parameters were determined by using X-ray diffraction, XRD. Mic...

Three types of inexpensive Pb-free solder joints, namely Zn-based and Bi-based solders, and a CuSn alloy were studied for application to the high-temperature operation of wide band-gap power semiconductor devices using GaN or SiC. Zn– Al solder sheets, whose melting point is 380°C were prepared, and then surface oxides were removed by RF plasma etching. Subsequently, Cu thin films were deposite...