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The purpose of this paper is to evaluate the effect of seawater temperature on the corrosion behaviour of 90‐10 cupronickel alloys. Also, to investigate the effect of thiosulphate additions (one of the major sulphide oxidation products in seawater) on the alloy corrosion rate in seawater.

Potentiodynamic polarization measurement (DC) was used to estimate the corrosion rate of the cupronickel alloy in seawater with and without thiosulphate species (50‐650 ppm).

It was observed that the cupronickel alloy suffered accelerated corrosion as the seawater temperature was raised from 25 to 50 or 80°C. The increase in the corrosion rate was found to correspond well with the negative shift in the free corrosion potential. Thiosulphate addition was found to depend on the test temperature. At 25°C, thiosulphate activated the alloy dissolution rate and the higher were the thiosulphate concentrations, the higher was the corrosion rate. At 50 or 80°C, however, thiosulphate promoted the dissolution rate at early stages, but seemed to interfere with the surface film formation later on, producing a black film that effectively decreased the alloy corrosion rate. At higher potentials, however, the film became non‐protective, leading to accelerated corrosion once again.

This paper explains the corrosion behaviour of 90‐10 cupronickel alloys in seawater as a function of test temperature and thiosulphate additions.

Cleaning and descaling of metals. An improved process is described for cleaning, descaling and deoxidation of metals, especially stainless steel. A treating bath acts directly on the scale or oxide itself. Advantages cited are the decrease in time required as compared with the acid‐pickling process, decrease in metal loss to 10 lb./ton, elimination of pickling‐waste disposal problem, reactivity of the bath with C, decreased etching of the metal surfaces, and low cost and simplicity of operation. Thus, in cleaning a Ni‐Cr alloy steel, the complete cycle for satisfactory oxide removal is as follows: 6 to 7 min. in fused NaOH + 5% NaNO3 at 900°F., or 4 to 5 min. at 950°F., water quench, and treatment in 10% HCl at 180° for 1 min. followed by 15 sec. in 15% HNO3 at 180°.—U.S. Pat. 2,678,289, James H. Noble, Rolfe Pottberg and Urlyn C. Tainton.

PART IV Inorganic chemistry textbooks. Seventeen textbooks of inorganic chemistry are considered in this part of the review, and the inorganic sections of the syllabuses of the three GCE Boards previously discussed are analysed.

The aim of this study was to test and survey a circuitry transfer technique where conductor patterns are electroformed on carrier substrates and thereafter the electroformed patterns are transferred from carrier substrates to their final devices.

An electrically conductive pattern is built up by an electrodepositing metal or metal alloy on a carrier substrate, called a mandrel, using a resist image to define the outlines of the pattern. Thereafter, the electroformed structures are bonded on plastic substrates, for instance, by hot pressing or by embedding into a resin. In our experiments, the imaging of stainless steel carriers was done by the photolithographic process and the electroformed copper patterns were transferred by hot pressing onto thermoplastic substrates.

The literature review revealed that the transfer of electroformed conductor patterns to plastic parts is not a very commonly used technology, although it could provide possibilities for even quite specific structures in electronics manufacturing at an affordable price. Our tests indicated that the acidic peroxide-sulfuric pre-treatment of electroformed copper patterns before hot press bonding clearly improved the adhesion of copper on both acrylonitrile butadiene styrene and polyphenylene oxide substrates and that a steel template around the substrate during hot pressing process can restrict dimensional changes in thermoplastic substrates significantly.

This paper contains a survey and preliminary testing of the electroformed circuitry transfer technique. The analysis of the test boards focused on the adhesion between copper strips and thermoplastic substrates and on the factors affecting adhesion. Finally, the paper introduces the advantages and drawbacks of the technique.

A new area for the maintenance coatings specialist is found in nuclear installations where coatings are necessary which are not contaminated by radioactive materials or which are readily cleaned if there is suspicion of contamination. The testing of coatings for nuclear containment has been discussed in an article by Burger (Metal Finishing, May, 1982, p. 127). Such coatings, the author points out, must be able to withstand exposure to high humidities and, at the same time, exposure to radiation dosage. In addition, the coatings must be sufficiently durable to withstand the conditions which would be anticipated during an accident. To meet these challenges provides a new opportunity for coatings chemists. A bibliography related to testing of nuclear coatings is listed by the author, and from these he concludes that the most significant are the Design Basis Accident or DBA test. This is a test to tell whether the coating will stand up if, in fact, there is an accident. The second test relates to irradiation, and the third to decontamination factors. These are described in detail by the author. He points out that a coating that passes these tests will meet the 40‐year expected life within a nuclear power containment facility.

The purpose of this paper is to develop a new ionic compound free soldering process.

The ability of hydrocarbons including 9,10‐dihydroanthracene, eicosane, 2,6,10,14‐tetramethylpentadecane, cyclooctane, and dicyclopentadiene to reduce cuprous or cupric oxide was investigated. The applicability of hydrocarbons as ion free flux reagents was experimentally examined. The hydrocarbons were applied to the soldering of pre‐oxidized copper electrodes under practical conditions.

A 9,10‐dihydroanthracene was found to be efficient at reducing cuprous or cupric oxide powder under an argon atmosphere at 300°C for 2 min. The high‐reducing ability of the hydrocarbon is in agreement with the low‐homolytical C−H bond dissociation energy calculated based on the density functional theory. A 9,10‐dihydroanthracene was shown, by the highest soldering efficiency and sufficient reliability in the environmental testing, to be applicable as an ion‐free soldering flux.

The findings of this paper suggest a new method for an ionic compound free soldering process.

Two sets of formulations based on three copolymer and three terpolymer systems involving tributyltin methacrylate(BTMA),methyl methacrylate(MMA) and acrylonitrile (AN) with variable tin contents of 7, 15 and 22% were prepared. There is only one varient in each formulation of the six prepared, that is the type of organotin polymer whether it is a copolymer or terpolymer of a definite tin content 7 or 15 or 22%. The binder mixture is a blend consisting of the organotin polymer, a vinyl copolymer and its external plasticizer and little amount of rosin. A moderate and fixed amount of cuprous oxide was introduced into all formulations as a supplementary toxin with organotin polymer. Leaching rates of micro amounts of copper and tin were determined. Panel exposure test in the sea was performed at Port Said. Best antifouling efficiency was obtained from formultions containing organotin copolymer or terpolymer of 22% tin content and that containing organotin copolymer of 15% tin.

The effect of pigment filler and extender on the antifouling efficiency of six compositions containing organotin polymer is studied. The binder mixture is a blend containing a copolymer of tri‐n‐butyltin methacrylate and methylmeth acrylate (OTP) with 22% tin content, a vinyl copolymer with its external plasticizer and little amount of rosin. Cuprous oxide was added as a supplementary toxin with the OTP. Leaching rates of microamounts of copper and tin were determined for a period of nearly one year applying standard techniques. Painted plates were immersed in Suez Canal waters at Port‐Said for more than 36 months. Comparison between different fillers and extenders on the antifouling behaviour of painted surfaces is shown. Compositions containing cellite and china clay exhibited the maximum antifouling performance.