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A wide field of applications for vacuum coatings has been opened up by the development of techniques for producing thicker protective coatings and, in some cases, aluminium coatings may replace nickel‐chromium plating. The coating process and basic equipment are discussed herein and an account given of the properties and applications of commercially produced aluminium and cadmium coatings.

Geigy Co. Ltd. Stand 75. Diversified application of benzotriazole as a corrosion inhibitor specifically for copper and its alloys is the main theme of Geigy's stand.

Every metal has a range of environmental conditions against which it is resistant or sufficiently resistant as to make the metal economically feasible. Unfortunately it is almost a rule of thumb that the more expensive the metal the smaller the range. In most cases the resistance of the metal is a function of the metal thickness, but the function is such that relatively thin metals can produce very long lives.

Sprayed metal coatings are an alternative means of effectively protecting steel structures and equipment exposed to severe environments where other coatings, such as paint, are unsuitable or provide only temporary protection. Selecting the most suitable material for a given application is a very important step in achieving success. For resistance to corrosive environments, zinc and aluminium are the most successful and widely used coatings, both being anodic to iron and steel. The performance of sprayed metal coatings is a function of the environment, coating thickness, adhesion, density and the type of sealer used. The mechanism of adhesion is mainly mechanical, the bond strength being dependent on the application process chosen and standard of surface preparation. This paper describes the results of research work associated with hot sprayed aluminium applied by combustion flame and electric arc processes using compressed air and argon carrier gases. Studies included ductility and adhesion tests, scanning electron microscopy of surfaces and cross sections, and Auger surface analyses.

Sprayed metal coatings have a characteristic structure which greatly influences their behaviour in corrosion processes. The coatings are built up from tiny particles of metal, of the order of 20 microns diameter, produced by atomising molten metal in a stream of compressed air. The metal is supplied to the spraying pistol either as a wire or a powder and is melted in an oxygen‐fuel gas flame. The metals of low melting point, including zinc and aluminium, are also applied by a pistol which receives molten metal from a heated reservoir.

Introduction Surface coatings of metal are applied chiefly to iron and steel, but sometimes also to non‐ferrous alloys, in order to improve the appearance or to increase corrosion resistance. Increased corrosion resistance may be obtained in either of two ways: (1) a more protective or noble metal is applied, or (2) a less noble or sacrificial coat is formed.

The purpose of this study is to use polybenzoxazine (Pbz) functionalized ZrO₂ nanoparticles to synthesize polyurethane (PU)-PbZ/ZrO₂ nanocomposite. The results derived from the electrochemical impedance spectroscopy (EIS) and polarization studies indicated the superior anticorrosive activity of PU-Pbz/ZrO₂ nanocomposite coatings compared to those of plain PU coatings. The decreased corrosion current was detected on the scratch of the PU-Pbz/ZrO₂ nanocomposite-coated mild steel surface by scanning electrochemical microscopy (SECM) compared to other studied coatings. The superior anticorrosive and mechanical properties of the proposed nanocomposite coatings provide a new horizon in the development of high-performance anticorrosive coatings for various industries.

The Pbz functionalized ZrO₂ nanoparticles were characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) and thermogravimetric analysis (TGA) in terms of the structural, morphological and thermal properties of these coatings. A different formulation of coatings such as PU, PU-Pbz, PU-ZrO₂ and PU-Pbz/ZrO₂ were prepared and investigated for their corrosion protection performance on mild steel in natural seawater by electrochemical techniques. The surface morphological studies were done by SEM/EDX and XRD analysis.

The superior anticorrosive property of the proposed nanocomposite coatings provides a new horizon in the development of high-performance anticorrosive coatings for various industries. Addition of Pbz wrapped ZrO₂ nanoparticles into the PU coating resulted in the blockage of charge transfer at the metal/electrolyte interface, which reduced the dissolution of mild steel. It was revealed from the SEM/EDX analysis that the formation of the corrosion products at the metal/electrolyte interface behaved as the passive layer which reduced the dissolution of steel.

The inclusion of polybenzoxazine functionalized ZrO₂ nanoparticles to the polyurethane coating reinforces the barrier and mechanical properties of PU-Pbz/ZrO₂ nanocomposite, which is due to the synergistic effect of ZrO₂ and Pbz.

The coating of plastics has occupied the attention of polymer chemists for the past 30 years. Several problems are immediately obvious. If the coating is a hard resistant thermoset like a baked phenolic, it provides a surface to which every few substances will adhere: Two generations ago all telephones were black for this reason. If on the other hand the polymer is thermoplastic, adhesion is not necessarily a problem but solvents are, since the solvent in the coating can erode the polymer's surface. Plastic surfaces require coating for a number of reasons and this has caused imaginative chemists to devise new coatings and new coating techniques to meet the challenges. Some plastics require coatings simply for decoration. Some require coatings in order to protect the surfaces. This is particularly true in the electronics area. The need for coatings for plastics has been accelerated by the desire of the automotive industry to replace metal with polymers. If the plastic is part of the automobile body it must be coated to match perfectly the coated metal part. Reaction injection moulding (RIM) is providing a means for supplying the automotive industry with large parts such as bumpers, fascias, and in the not too far future doors and hoods. Naturally the coatings on these must duplicate precisely the coating on the metal portions of the car.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

From November 29 to December 2 the Empire Hall at Olympia, London, will be given over to what will probably be the world's largest display of products, processes and services for use in the prevention or limitation of corrosion. Over 120 stands will be shared by 94 exhibitors, each contributing in some way or in many ways to this cause. The extensive preview in the following pages is divided into sections. However, the grouping is general and reflects only one aspect of a company's activities. Therefore a complete examination of items is recommended.