Chemical Research and Corrosion Control: Some Recent Contributions of a Corrosion Research Group

Abstract

immerse %o rrosion tests ; the investigation of high-duty coatings ;the Corrosion Research and Industrial R e s y h ) , Teddington, since 1 9 p The topics $SCUSSC includphe high-speed rotor apparatus for accelentcd antifreeze solutions ; corrosion inhibitors for use in hear-exchange systems, de-icing systems, wrapping materi Is, enclosed air spaces ; accelented atmospheric corrosion tests ethods of preytreatmiscellaneous investigations and infomition services.sustained during his subsequent partial retirement), the work of the " Corrosion Section " was reviewed, immediately prior to the war, in 1939.' The present survey is intended to cover the period since that date ; it represents throughout, as should be emphasised, the work of various members of a research team. Most of this work has been concerned with specific war-time problems and has been carried out for Service and Defence Departments. It is hoped that 'matters now dealt with very summarily may in due course be amplified in formal publications. High-speed rotor apparatusThe ' I High-speed Rotor Apparatus yy2 is based on researches carried out in the Section prior to the period under review ; it was originally designed to investigate the corrosion resistance of unpainted metals to fresh waters or sea-water under conditions of rapid movement. Each unit carries six specimens ; these are mounted in a circular ebonite holder, which is itself carried by an ebonite-covered steel spindle, driven by a 4 hap. electric motor.The spindle is inclined to the vertical, in order to avoid an undesirable vortex effect in the rectangular glass tank in which the liquid is contained. The specimens are small (I in. square), but when mounted flush in the holder their surfaces form virtually part of the rotating surface j they are normally insulated from each other, but can, if desired, be interconnected within the holder. This is normally rotated at a speed of 1500 r.p.m., giving a peripheral speed (checked by a simple stroboscopic device) of approximately 20 knots.

Polymer/layered silicate nanocomposite anticorrosive coatings

“…Most inhibitors have been developed by empirical experimentation, and many inhibitors are proprietary in nature and thus their composition is not disclosed. Inhibition is not completely understood because of these reasons, but it is possible to classify inhibitors according to their mechanism and composition [109][110][111][112][113][114][115][116][117][118][119][120][121][122][123][124][125][126][127]129]. …”

“…Typical changes in the medium that are often employed are (1) lowering temperature, (2) decreasing velocity, (3) removing oxygen or oxidizers, and (4) changing concentration. In many cases, these changes can significantly reduce corrosion, but they must be done with care[109][110][111][112][113][114][115][116][117][118][119][120][121][122][123][124][125][126][127][128].…”

“…This category involves integral or solid nonmetallic construction (mainly self-supporting) and also sheet linings or coverings of substantial thickness (to different from paint coatings). The five general classes of nonmetallics are (1) rubbers, natural and synthetic; (2) plastics; (3) ceramics; (4) carbon and graphite; and (5) wood[109][110][111][112][113][114][115][116][117][118][119][120][121][122][123][124][125][126][127].6.2.1.4. Changing mediums.…”

“…Metals and alloys.The most common method of preventing corrosion is the selection of the proper metal or alloy for a particular corrosive service. Since this is the most important method of preventing or reducing corrosion damage[109][110][111][112][113][114][115][116][117][118][119][120][121][122][123][124][125][126][127].…”