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Coal‐tar and asphalt‐base coatings have been the major protective coatings used on pipelines for nearly half a century. The coal‐tar coatings are the only ones recognised for use as a lining and coating for water‐lines, but in oil and gas systems both types are being used. The coal‐tar hot‐applied coatings have dominated even this field. It is estimated that, since the war, the amount of the two types of hot‐applied coatings used in the Western hemisphere has varied between 200,000 and 350,000 tons p.a. and the percentage of hot‐applied asphalts used has varied between 10 and 30%.

Polyurea falls into a category of elastomeric co‐polymers in which, due to the presence of strong hydrogen bonding, the microstructure is of a heterogeneous nature and consists of a compliant/soft matrix and stiff/hard nanometer size hard domains. Recent investigations have shown that the use of polyurea as an external or internal coating/lining had substantially improved ballistic‐penetration resistance of metallic structures. The present work aims to use computational methods and tools in order to assess the shock‐mitigation ability of polyurea when used in the construction of different components (suspension‐pads, internal lining and external coating) of a combat helmet.

Shock‐mitigation capability of combat helmets has become an important functional requirement as shock‐ingress into the intra‐cranial cavity is known to be one of the main causes of traumatic brain injury (TBI). To assess the shock mitigation capability of polyurea, a combined Eulerian/Lagrangian fluid/solid transient non‐linear dynamics computational analysis of an air/helmet/head core sample is carried out and the temporal evolution of the axial stress and particle velocities (for different polyurea augmented helmet designs) are monitored.

The results obtained show that improvements in the shock‐mitigation performance of the helmet are obtained only in the case when polyurea is used as a helmet internal lining and that these improvements are relatively small. In addition, polyurea is found to slightly outperform conventional helmet foam, but only under relatively strong (greater than five atm) blastwave peak overpressures.

The present approach studies the effect of internal linings and external coatings on combat helmet blast mitigation performance.

Nordbak Wear Tech ‘T’ gives water pump another five years hard labour. Prior to the application of Nordbak Wear Tech ‘T’ to provide a tough epoxy/resin lining, this heavy duty water pump was wearing out to perforation point in local areas within six to nine months due to chemical attack. Operating in a dredge pond, the water was excessively acidic due to the presence of anaerobic sulphate reducing bacteria which generated hydrogen sulphide.

The end of this month will see Britain's biggest display of products and processes designed to prevent the onset of corrosion in all its forms. At the Royal Horticultural Society's New Hall, in Westminster, there will be over a hundred stands on view to visitors to the Exhibition which will run from April 27 to 30 inclusive. Here is C.T.'s exclusive preview. Stand descriptions are grouped under various headings, but the fact that a firm's exhibits are described under one heading does not necessarily mean that its interests are confined solely to that group of products. The grouping of exhibitors in this preview is merely intended to facilitate visitors who are interested in particular aspects of corrosion prevention.

In part one of this article (August 1964) the author dealt with the general chemistry, curing characteristics and applications of two‐pack and coal tar‐epoxy coatings. Part two discusses other types of epoxies and describes their uses as corrosion‐resistant coatings and pipe linings.

Because of their corrosion resistance, the ease with which they can be worked and their ready availability, PVC and polythene are now widely used in the construction of plant and equipment ranging from beakers and valves to large gas‐washing plants. Here the author discusses first the limitations of these materials and then describes how they are applied to fabricated structures and equipment, linings, coatings and cements. Brief mention is made of other modern plastics. This article is substantially the paper which the author gave at a symposium on the fabrication of PVC and polythene at the College of Technology, Birmingham, on April 8.

The problem of disposing of radioactive effluents is growing bigger as more nuclear plants are built and industry generally makes increasing use of radioactive chemicals in research. Here the author attempts to assess the value of various corrosion‐resistant materials of construction for effluent systems designed to handle radioactive liquids. He concentrates on non‐metallic materials such as rubbers, plastics and concrete and describes a number of special cements.

COATINGS AND LININGS. Urethane floor coatings. An American firm has developed a new, high‐build urethane floor coating said to possess excellent flexibility, elongation and chemical ‐ resistance properties. Known as Carboline Urethane 1323, it has all the major advantages of the commonly‐used epoxy, phenolic and polyester types, and can be sprayed with conventional equipment or trowelled over concrete, primed steel, acid‐proof brick and wood at thicknesses from 20–100 mil in one coat.

This paper aims to presents a new method of investigation of local properties of conformal coatings utilized in microelectronics.

It is based on atomic force microscopy (AFM) technique supplemented with the ability of local electrical measurements, which apart from topography acquisition allows recording of local impedance spectra, impedance imaging and dc current mapping. Potentialities of the proposed AFM-assisted approach have been demonstrated on commercially available epoxy-coated electronic printed boards in as-received state and after six-year service.

The technique proved to be capable of identification, spatial localization and characterization of conformal coating defects.

The proposed approach can be utilized for assessment of protective film state in such demanding fields as electronics or electrotechnics where the classical techniques of anticorrosion coatings investigation cannot be employed due to small element dimensions and relatively low coating thickness.

The approach adopted by the author is novel in the field of organic coatings investigation.