[en] A revision of the phase diagram of the Pt-Zr system is presented using up to date information from recent publications. The proposed change concerning the invariant transformation in the Pt-rich zone is supported by simplified thermodynamic evaluations. (author). 12 refs., 1 fig

[en] The “Shrink-fit ring and plug” system is known in the residual stress neutron community mostly due to the VAMAS Round Robin specimens, that were measured by most of the neutron residual stress instruments worldwide. This standard, however, can be challenging for some low flux instruments and considerable beamtime and efforts are required to accomplish measurements accordingly to the measurement protocol. Theoretically, the residual stress distribution is not simple, being neither plain stress nor plain strain, and essentially it is a 3D distribution with a large gradient toward the flat cut, especially for the axial component. Another “shrink-fit ring-and-plug” system is being considered, namely bi-metallic coins. With an easier zero plane stress state, they represent another potential candidate for a standard. Bi-metallic coins are in current circulation in many countries of the world. In the given study we report on an assessment of the residual stress state of 7 different bi-metallic coins measured by means of neutron diffraction to reconstruct the full stress state. The magnitudes of the stresses in the specimens were different obviously due to differences in the coinage process and materials in use. While in some cases residual stresses are weak and therefore difficult to measure accurately, in some cases stresses reach ~100 MPa. Although question in variability of the coinage process through years and within series is still debatable, tight standards and tolerances of the mint industry suggest the probability of consistency in the residual stress state making bi-metallic coin an interesting alternative to the VAMAS ring-and plug standard. (author)

[en] Powder metallurgy process (P/M) is a near-net or net-shape manufacturing process that combines the features of shape making technology of powder compaction with the development of final material and design properties (physical and mechanical) during subsequent densification or consolidation processes, e.g. sintering. It utilizes the metal powder or powders of metal alloys. In this paper, the major historical developments in P/M are reviewed and discussed. The main parameters involved in the process and their effects on the product characteristics are presented and discussed, which include: powders and methods of their production, particle size and shape, compressibility and additives, sintering temperature and time and finishing processes. The advantages and limitations of powder metallurgy are also presented and discussed. Finally, applications and future developments of the process are outlined and discussed. (author)

[en] Small amount of certain alloying elements changes the oxidation behavior of tin. Electrochemical anodic oxidation of Sn-Pb alloy with different percentages of Pb has been investigated in sulphuric acid, sodium hydroxide, and sodium chloride and on these electrodes. The reduction of maleic acid in sulphuric acid has been tried. The formation of stannous oxide is thermodynamically favored and that the elements that enter the oxide with valence greater than tin increase the rate of formation of stannous oxide appears to be reasonable. When the formation of stannous oxide is not favored, the alloying element is oxidized preferentially on the surface of the alloy in the form of a thin oxide film and discrete crystallites. (author)

[en] A particle reinforced metal matrix composite (PRMMC) consists of a uniform distribution of strengthening ceramic particles embedded within a metal matrix. In general, these materials exhibit higher strength and stiffness, in addition to isotropic behavior at a lower density when compared to the un-reinforced matrix material. From the mechanical behavior standpoint the main drawback of theses materials is their reduced ductility, believed to be caused by the nucleation, growth and coalescence of voids due to the presence of the ceramic reinforcements. The main objective of this paper is to determine the damage and failure processes of PRMMC caused by tensile loadings. This study, through the use of SEM fracture analysis, shows that the main fracture mechanism is based on void nucleation. Tests results also show that both the modulus of elasticity (E) and tensile strength, increased with the increase in volume fraction of the reinforcements. (author)

[en] Over the last twenty years, tremendous progress has been achieved in the field of Metal Organic Frameworks. Among these materials, the zirconium terephthalate UiO-66(Zr) [1] has attracted a growing attention because of its interesting thermal, chemical and water stability and has shown to be a promising material for the separation of CO2/CH4 gas mixtures. In order to get a better understanding of its sorption behavior towards these gases, a Neutron Powder Diffraction (NPD) investigation of UiO-66 loaded with sequential doses of CO2 and CD4 has been carried out on the High Resolution Powder Diffractometer instrument “Echidna” at the OPAL reactor (ANSTO, Sydney). In total, three adsorption sites for CO2 and three adsorption sites for CD4 within the UiO-66(Zr) have been located by NPD then characterized by a combination of first-principles Density Functional Theory (DFT) calculations, binding energies and Quantum Theory of Atoms In Molecules (QTAIM) theory. An example of the first CO2 adsorption site is given in figure 1.

[en] The temperature dependent dynamic properties of Palladium (Pd) and Aluminum (Al) noble metals and their alloys are investigated by means of Molecular Dynamics using the Quantum Sutton-Chen force field in five different concentrations. Calculations have been carried out for melted liquid structures. Although this study is done for melted alloys, basic solid state properties are also investigated to prove the validity of potential parameters. Results are compared with each other and with experimental, theoretical and simulated results. Liquid state transferability of Quantum Sutton-Chen parameters have been investigated and discussed. High temperature properties, which are not easy to work experimentally, are simulated and high temperature behavior of Pd-Al alloys are investigated

No abstract available

[en] Liquid properties of Rh-Ir metal alloys are calculated by Molecular Dynamics (MD) simulation with the use of Sutton-Chen potential (SC) energy function. The thermodynamical and structural properties of the alloy investigated. The melting temperatures of Rh-Ir alloys predicted. The transition property of the potential is tested by simulation of liquid state. The values of melting point are in agreement with the experiment.

No abstract available