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In this work seven simple and advanced neutron and γ ray shielding materials were investigated in order to stop both neutrons and photon which produces through Be(p,n) reaction in beryllium target. The proton beam examined for three different energies: i) for 2.57 MeV, ii) for 3 MeV and iii) for4 MeV. As candidate neutron materials were examined the magnesium borohydride, the titanium hydride, the high density polyethylene, the zirconium borohydride, the lithium hydride, the magnesium hydride and the zirconium hydride. For the case of γ rays were simulated the performance of lead, bismuth, tungsten, di-tungsten boride, tungsten boride, di-tungsten penta-boride and tungsten tetra-boride. The simulations, which take place with the help of MCNP5 Monte Carlo code, reveal considerable superiority of some special materials such as the magnesium borohydride. In the case of photons tungsten with the highest density is the most suitable choice. [ABSTRACT FROM AUTHOR]

Hydrogen-containing materials are used in nuclear reactors to slow down fast neutrons, since the mass of hydrogen is almost equal to the mass of a neutron. Titanium hydride is used as an absorber for fast neutrons, since a fairly large number of hydrogen atoms can be dissolved in the titanium crystal lattice. However, its use is limited by the low dehydrogenation temperature. This paper presents a method for applying a coating W on the surface of a titanium hydride shot by the method of dual magnetron sputtering and studying the structure and morphology of the coating. The W coating was successfully applied to titanium hydride shot. Homogeneous and dense coatings 0.56 µm and 1.20 µm thick were obtained on titanium hydride shots. It has been found that with an increase in the coating thickness, the deposited film W undergoes structural changes from the β-W to the α-W phase. The use of a uniform coating W on the surface of a titanium hydride shot formed by dual magnetron sputtering can be considered as an effective way to slow down the dehydrogenation process. [ABSTRACT FROM AUTHOR]

The present article provides a detailed heat balance description of the metal hydride container intended for hydrogen separation from syngas. The proposed concept of a separator intended for hydrogen separation from syngas offers a solution to a one of main problem associated with the use of metal hydride alloy powders their low thermal conductivity. In order to eliminate big temperature differences in the alloy, a heat transfer intensifier was implemented in the metal hydride alloy volume; the intensifier was made of metal and exhibited high thermal conductivity. For the purpose of comparing the thermal fields, the first stage comprised the creation of a numerical simulation of hydrogen absorption without the use of an intensifier. Subsequently, three different geometries were created for an intensifier intended to remove heat from the metal hydride alloy powder towards the separator cover, and the effects of these three geometries were analyzed. The implementation of heat transfer intensifiers into the metal hydride alloy powder improved the heat removal by as much as 43.9 % and increased the thermal field homogeneity by 77 %. A result of the heat removal optimization was an increase in the hydrogen absorption kinetics and the efficiency of the separator operation. [ABSTRACT FROM AUTHOR]

Within the framework of import substitution, obtaining a new modern type of foamed metal is strategically important, which in the future can widely expand the possibilities of its use. Foreign experience of commercial proposals for the production of foamed metals is currently represented mainly from products made on the basis of aluminum or nickel powders with the addition of foaming agents in the form of titanium hydride, but it is an expensive component of foamed metals. To obtain new types of porous metals, it is essential to find new types of foaming agents, which should be less expensive in terms of cost and ease of production. The mechanisms and technological scheme of one of the main types of obtaining a porous structure of aluminum are considered. A study of the process of obtaining a new type of foam metal material with new types of foaming agents obtained from the waste of production in comparison with other types of porous metals and their foaming agents, such as titanium hydride, various types of carbonates, etc. [ABSTRACT FROM AUTHOR]

This article discusses the growing trend in using MIM technologies in manufacturing small titanium parts with complex geometric configurations for aerospace and other industries. Mechanical properties can be affected by: density, oxygen, carbon, and nitrogen content, microstructure, and doping content. It is proven, that oxygen degrades required properties of the parts obtained from titanium and its alloys using MIM technology. These properties particularly include tensile ductility, cold processibility, fatigue strength and resistance to stress corrosion. Using fine powder of spherical configuration improves purity of the surface of the final sintered products. However; it increases the content of impurities, in particular oxygen. It is shown, that the technological possibilities for obtaining parts using MIM-Ti are limited to sizes up to 0.05 m and weight up to 0.05 kg. Main factors of technological limitations in size and weight are the configuration of the part itself, the source material, and processing conditions. As an alternative to expensive spherical powders, it is possible to use titanium hydride powder. [ABSTRACT FROM AUTHOR]

This work explains about the fabrication of Magnesium reinforced with aluminum, copper, zinc with yttrium metal foam with titanium hydride as foaming agents and calcium stearate as binding agent. The pellets are prepared by powder metallurgy method at a dimension of 20mm diameter and16mm thickness. The sintered samples are tested for mechanical characteristics. The results of mechanical characteristics for the composition Mg-Al-Cu-Re has the highest load bearing capacity of 52.24kN. The composition Mg-Al-Cu-Re has the highest Compressive strength capability of 163.82Mpa. Hardness value with the composition Mg-Al-Re has the highest hardness value of 204.88VHN. Energy absorption for the composition Mg-Al-Cu-Zn-Re has the highest energy absorption characteristics of 186.944KJ because energy absorption is directly proportional to the porosity of the sample. This work explains about the fabrication of Magnesium as parent metal reinforced with aluminum, copper, zinc with yttrium metal foam with titanium hydride as foaming agents and calcium stearate as binding agent. The pellets are prepared by powder metallurgy method at a dimension of 20mm diameter and 16mm thickness. The sintered samples are tested for their mechanical characteristics by compression and hardness tests. The results of mechanical characteristics for load vs displacement with the composition Mg-Al-Cu-Re has the highest load bearing capacity of 52.24kN. Stress vs strain the composition Mg-Al-Cu-Re has the highest stress bearing capability of 163.82Mpa. Hardness value with the composition Mg-Al-Re has the highest hardness value of 204.88VHN. Energy absorption for the composition Mg-Al-Cu-Zn-Re has the highest energy absorption characteristics of 186.944KJ because energy absorption is directly proportional to the porosity of the sample [ABSTRACT FROM AUTHOR]

Titanium hydride (TiH2) powders are used to enhance the foaming process in the formation of a highly porous metallic material with a cellular structure. But, the low temperature of hydrogen release is one of its problems. The present study, different thermal pre-treatment temperatures were employed to investigate the decomposition behavior of TiH2 to retard or delay a hydrogen gas release process during foaming. As a foaming agent, TiH2 was subjected to various heat treatments prior at 450 and 500°C during 2 hours in argon condition. To study the formation mechanism, the thermal behavior of titanium hydride and hydrogen release are investigated by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The morphology of pre-treated titanium hydride powders were examined using Scanning Electron Microscope (SEM) while unsure mapping and elemental composition of the pre-treated powders processed by Energy Dispersive Spectroscopy (EDS). To study the phase formation was characterized by X-ray diffraction analysis (XRD). In accordance with the results, an increase in pre-treatment temperature of TiH2 to higher degrees are changing the process of releasing hydrogen from titanium hydride powder. DTA/TGA results showed that thermal pre-treatment TiH2 at 450°C, released the hydrogen gas at 560°C in heat treatment when foaming process. Meanwhile, thermal pre-treatment in TiH2 at 500°C, released the hydrogen gas at 670°C when foaming process. There is plenty of direct evidence for the existence of oxide layers that showed by EDS analysis obtained in SEM. As oxygen is a light element and qualitative proof shows that the higher pre-treatment temperature produces more and thicker oxygen layers on the surface of the TiH2 powder particles. It might the thickness of oxide layer are different from different pre-treatment temperatures, which leading to the differences in the decomposition temperature. But from SEM result that oxidation of the powder does not change the powder morphology. The oxidation process also confirmed by XRD result, which showed higher thermal pre-treatment TiH2, more oxide higher peak is formed. The oxide layer of TiH2 particles is responsible for the observed shift in decomposition temperature and can prepare the stable foam that stabilizes forming of cell walls and avoid their collapse at higher temperatures. [ABSTRACT FROM AUTHOR]

The resistance seam weld interfaces between alloyed and pure titanium are an in service concern due to precipitation of titanium hydride and resulting embrittlement and cracking. Several inspection techniques were developed and evaluated for field use to characterize the damage in the fleet. Electromagnetic, ultrasonic, florescent penetrant, thermographic, and radiographic techniques were considered. The ultrasonic and electromagnetic approaches were both found suitable. However, the electromagnetic approach is more desirable for field inspections, due to consistency and ease of use. The electromagnetic inspection procedure is able to discriminate between precursor damage and through cracking with sufficient sensitivity to small cracks. [ABSTRACT FROM AUTHOR]

Transmission Elastic Recoil Detection (ERD) was used for profiling hydrogen in α+γ phase titanium hydride. Titanium foils 25 μm thick were electrolytically loaded with hydrogen from aqueous HCl and NaCl to form a heterogeneous layer of α+γ phase titanium hydride on the surface. The foils were cyclically annealed between 250° C and 340° C and quenched at 304° C which resulted in homogenous titanium hydride across the thickness. An empirical formula was determined from the data to predict the uniform hydrogen concentration as a function of loading time during electrolysis. Hydrogen concentrations up to 41 at% can be controlled using this technique. The effects of electrolyte concentration and electric cell current on the initial hydrogen profile are reported. Longer loading times to obtain concentrations greater than 41 at% are also investigated. [ABSTRACT FROM AUTHOR]

The elastic and ground state properties of 3d transition metal mono hydrides TMHs (TM = Ti, V), which crystallize in NaCl-type structure, has been performed using DFT based VASP code at ambient pressure. The calculated ground state properties such as lattice constants are compared with the available results. A pressure induced structural phase transition from NaCl phase to hexagonal (NiAs) phase is observed for both TiH and VH. [ABSTRACT FROM AUTHOR]