Using a pair bond type model for the interatomic interactions. we determine surface scgregation on clean, H, 0 and CO covered surfaces of various alloys. Furthermore, we study surface segregation caused by bulk hydrogen absorption. Numerical results are presented for Pd ,Zr, ~ H, We find, that strong surface segregation may result from chemisorption of 0 and CO and from absorption of H in the b...

The present work aims to reveal the dispersoids evolution and valuable role of Zr on elevated-temperature creep resistance Al–7Si-0.3Mg alloy. At 300°C 25 MPa, Al–7Si-0.3Mg-0.15Zr alloy exhibits more than double decrement in minimum rate, 263 h increment time-to-fracture compared Zr-free cast These effects were owe formation novel nanobelt-like Si2Zr rectangle-like (Al, Si)3–Zr during solutioni...

To improve the understanding of the relation between composition, precipitation and the balance of strength and electrical conductivity (as a measure of the stress-corrosion resistance), a number of Al-Zn-Mg-Cu-Zr aluminium alloy plates with different Zn, Mg and Cu contents were produced and studied by Differential Scanning Calorimetry (DSC). It is shown that detailed analysis of the DSC data p...

The internal oxidation o f dilute Pd alloys has been studied by XAS. Pt, Au, Pb and Bi in Pd form no impurity-oxygen complexes. Y, Nb, Gd, Yb, Lu, H f , Th, Zr and Mo precipitate at 1050°C as oxides. In a recent paper /1/ it was shown how X-ray absorption spectroscopy (XAS) can be used to investigate the internal oxidation of impurities in dilute alloys. It was demonstrated in the case of a @Zr...

The heats of eutectic melting and devitrification, and the specific heats of the crystalline, glass, and liquid phases have been measured for a Ni,,Zr,, alloy. The data are used to calculate the Gibbs free-energy difference, AGAc , between the real glass and the crystal on an assumption that the liquid-glass transition is second order. The result shows that AG,, continuously increases as the te...

V ions exhibit cytotoxicity in a culture medium from concentrations of ^0.2 mg/L. Ti, Zr, Nb and Ta are biocompatible elements. A new Ti–15Zr–4Nb–4Ta alloy for medical implants is being developed. Its microstructure, mechanical properties, corrosion resistance and corrosion fatigue properties in a physiological saline solution, biocompatibility with cultured cells, new bone tissue response thro...

The phase analysis of Cu-0.41%Cr-0.20%Zr alloy treated by vacuum melting + solid solution aging was carried out means SEM, TEM, EDXS and XRD. results show that there are three phases in the alloy, namely copper matrix phase, chrome-rich zirconium-rich phase. distribution size is bimodal. coarse microns scale, main components elemental chromium Cu 5 Zr, which formed during casting process not ea...

Presently, LWR (light-water reactor) fuel cladding (tube) is made from Zr-base alloys (e.g., Zircaloy). However, in steam at temperatures above 1000 K (727 °C), these alloys oxidize rapidly, stripping oxygen from water molecules and producing hydrogen, which may cause explosion. Moreover, Zr-base alloys are prone to GTRF (“grid-to-rod” fretting) failure, in which flowinduced vibration of fuel r...

The effect of oxygen content on the microstructure and mechanical properties of the Ti-29mass%Nb-13mass%Ta-4.6mass%Zr (TNTZ) alloy was investigated in this study. The microstructural observation of TNTZ alloys, containing 0.1–0.4mass% oxygen, subjected to solution treatment shows the presence of a single phase. With an increase in oxygen content, the hardness, tensile strength, and Young’s modu...

Zr and Sc precipitate in aluminum alloys to form the Al3ZrxSc1−x compound which, for low supersaturations of the solid solution, exhibits the L12 structure. The aim of the present study is to model at an atomic scale the kinetics of precipitation and to build mesoscopic models so as to extend the range of supersaturations and annealing times that can be simulated up to values of practical inter...