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The effect of zirconium, zinc, calcium and rare earth group as the alloying elements on mechanical properties and corrosion behavior of magnesium alloys was investigated in the simulated body fluid.

Pure magnesium and the alloying elements were melted and zirconium was finally added to obtain different alloys. The castings were annealed and some samples were aged heat treated. X-ray fluorescence was used for the elemental analysis and LSV was used for electrochemical corrosion evaluations.

Results showed that corrosion resistance decreases with increasing zirconium content. The lowest corrosion rate was obtained for the samples containing 0.3% and 0.45% of Zr from annealed and aging heat-treated samples, respectively. Yield stress enhances with increasing the zirconium content and degrades by the aging heat treatment.

These alloys were studied for the first time. Effect of casting without using protective flux and vacuum furnaces. Effect of annealing at 440°C for 2 h and artificial aging at 200°C for 16 h. Alloy’s electrochemical behavior on the body’s simulation environment has been investigated. Improvement of mechanical properties after annealing heat treatment by high zirconium percentage.

Although the element zirconium was not, until quite recently, associated with the bulk market for oil based and latex paints, there are four established areas of application for zirconium compounds:—

In the anticorrosion field the rise of zirconium has been remarkable, especially since the oxide zirconia was regarded for some years as the main industrial outlet as it became applied in furnace linings and in refractory crucibles. Zircon in precious stones was the sole use before this, yet a first move towards identifying zirconium came when Martin Klaproth, a most efficient analyst of his period, analysed zircon and noted the presence of a new element. While Humphry Davy failed to decompose zirconia during his work on electrolysis, Berzelius reduced a zirconium compound by reduction with potassium metal within a closed tube, thus preparing impure zirconium as a black powder.

The purpose of this paper is to investigate the film formation mechanism of zirconium-based conversion layer on mild steel. In this way, different approaches were used to show the self-limiting film formation mechanism.

To determine this mechanism, film formation was detected using DC polarization, spectrophotometric technique and surface analysis techniques, including field emission scanning electron microscope (FE-SEM) and atomic force microscopy (AFM).

DC polarization resistance of surface increased with increasing of mild steel immersion time in the conversion coating bath, reaching to a plateau region. On the other hand, zirconium ion concentration decreased during the beginning of the film formation process and continued with a constant concentration, showing the expiry of the process after some minutes.

This paper deals with the film formation mechanism of the zirconium-based conversion layer that includes valuable findings to monitor the process.

The general behaviour of titanium and zirconium in pure chemical environments is summarised, and also the effects of common contaminants such as air and heavy metal ions that are present in many process streams. The beneficial effect of traces of soluble iron and copper and organic compounds in non‐oxidising acids is discussed and the relative effect of these upon the behaviour of titanium and zirconium pointed out. Information is provided upon the performance of titanium—0.15% palladium alloy under similar circumstances. The conclusion suggests that the behaviour of titanium and zirconium in various types of chemical plant is best determined by reference to in‐plant trials than by laboratory testing; the use of in‐plant corrosion probes is recommended.

The paper aims to address the formulation of zirconium and oxalicum additive-based lubricants for use in slide ways to meet the demands of high positioning exactness based on reduction in stick–slip and coefficient of friction over a wide speed range and compares the same with commercially available lubricant.

An investigation into the frictional properties and stick-slip behavior of lubricating oil is carried out using linear reciprocating tribometer and correlated with ultraviolet spectroscopic analysis.

It is observed that these transition metal additive compounds support in increasing the flexibility of the molecular chains leading to improved lubricity.

The lubricant additives considered for the current study are based on transition metals zirconium and oxalicum. It is observed that these additive compounds support in increasing the flexibility of the molecular chains, leading to improved lubricity.

Reports on a comprehensive study of the effects of different driers on film properties of alkyd resin. The driers selected for study were calcium naphthanate and the octoates of cobalt, manganese, lead and zirconium. The properties studied were hardness, adhesion, flexibility, film formation, skinning tendency, water and acid resistance, viscosity and drying time. Concludes that driers not only dry coatings (paints, varnishes, resigns, inks) but have significant effect on the film properties. Infers that a combination of manganese, lead and zirconium can be used as the most promising drier system for better coating properties.

Presents a new method for the numerical simulation of diffusion with phase‐change. The method is able to handle hysteresis and finite‐rate kinetics in the phase‐change reaction. Such phenomena are frequent in solid‐solid phase transitions. The model problem discussed concerns hydrogen migration and hydride precipitation in zirconium and its alloys, a problem of interest to the nuclear industry. With respect to previous ones, our method is the first to incorporate an implicit treatment of diffusion, thus avoiding mesh‐dependent stability limits in the time step. The CPU time can in this way be reduced by a factor of 10–20 in applications. Addresses, through numerical studies, convergence with respect to mesh refinement and reduction of the time step. Also reports on an application of the method to the simulation of laboratory experiments. Shows that the method is a powerful tool to deal with general phase‐change problems, extendable to other physical systems.

This paper investigates wetting and infiltration of zirconium diboride by copper and copper/boron alloys in order to more effectively create electrodes for electrical discharge machining.

A high temperature furnace outfitted with a video recording system was utilized to observe wetting angles between molten copper alloys and zirconium diboride at various temperatures. A parallel, investigation of the thermodynamics involved with oxidation in the system was also undertaken.

This study showed that zirconium diboride can be wet by pure copper under carefully controlled conditions where oxygen contamination is minimized, and that the wetting angle increases with increasing temperature. Thermodynamic calculations reinforce the contention that oxygen contamination is the key barrier to wetting and infiltration. The addition of boron to copper significantly improves the wetting characteristics, and enables wetting and infiltration under higher oxygen contamination conditions.

This study illustrated that boron must be added to copper to achieve infiltration when surface oxides are present.

Infiltration of porous 3D green shapes of ceramics and metals is a common method for producing metal and ceramic components using rapid prototyping. Good wetting of the porous material by the infiltrant material is necessary for successful infiltration using capillary forces. This paper illustrates the alloys and conditions under which it is possible to produce electrodes of zirconium diboride/copper using rapid prototyping.

The purpose of this paper is to develop a chrome-free and phosphorus-free chemical conversion coating with good corrosion resistance, a novel chemical conversion coating was prepared by adding cerium nitrate hexahydrate and salicylic acid in the treatment solution containing titanium/zirconium ions on 6061 aluminum alloy.

Compared with the AA6061 aluminum alloy matrix, the self-corrosion potential of the conversion coating is significantly positively shifted, the self-corrosion current density is greatly reduced and its corrosion resistance is significantly improved. Morphology and composition of the conversion coatings were observed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The microdomain structure of conversion coatings at different formation stages was analyzed by electron probe microanalyzer.

An optimized preparation technique of titanium–zirconium chemical conversion coating for AA6061 aluminum alloy is obtained: H₂TiF₆ 4 mL/L, H₂ZrF₆ 0.4 mL/L, salicylic acid 0.35 g/L, Ce(NO₃)₃·6H₂O 0.14 g/L, reaction temperature 30°C, reaction time 120 s and pH 4.0.

The coating forms on the Al(Fe)Si intermetallic compound, and Ce³⁺ is preferentially adsorbed on the intermetallic compound. The hydrolysis of Ce³⁺ causes the local pH of the solution to decrease, which promotes matrix dissolution and charge migration. As the microanode/microcathode reaction occurs, the local pH of the solution increases, and Al₂O₃/ZrO₂/TiO₂ begins to deposit on the surface of the metal substrate.