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This paper aimed to propose a novel fused-coating-based additive manufacturing (FCAM); the study of key process parameters and mechanical tests are performed to determine the proper parameters when building metal components.

Sn63Pb37 alloy is deposited in an induction heating furnace with a fused-coating nozzle to build metal parts on a copper-clad substrate. The process parameters including nozzle pressure, nozzle and substrate temperature and nozzle gap between substrate are analyzed and found to have great influence on parts quality. The mechanical property tests between the fused-coating and casting parts are performed in horizontal and vertical directions. Also, the optical microscopy images are used to ascertain under which conditions good bonding can be achieved.

A FCAM method is proposed, and the exploration study about the manufacturing process is carried out. The critical parameters are analyzed, and microscopy images prove the suitable temperature range that requires to fabricate metal parts. The mechanical tests confirm that tensile strength of printing parts is improved by 20.4 and 11.9 per cent in horizontal and vertical direction than casting parts. The experimental results indicate that there is a close relationship between process parameters and mechanical properties.

This paper proves that FCAM provides an alternative way to quickly make functional metal parts with good quality and flexibility compared with other additive manufacturing methods. Moreover, good mechanical property is achieved than conventional casting parts.

Instantaneous measurement of ultraviolet radiation intensity during accelerated weather and light‐fastness testing is now said to be possible with the introduction by Heraeus (Original Hanau division) of a new UV meter.

For more than a decade electrostatic paint spraying techniques have been making an increasing impact upon the product finishing and corrosion protection industries. These processes have now reached a very advanced stage of development and, in fact, some of the most up‐to‐date techniques and equipment were described last month in CORROSION TECHNOLOGY. However, young as the science of electrostatic spraying is, it has now reached its second major stage of development. This new and very recent phase is one which is already making itself considerably felt in the product finishing industry, but it is quite possible that its most profound effect will be felt by those who are more particularly concerned with corrosion protection. The new phase referred to is that of electrostatically spraying dry powder materials.

Protection by flame spraying. The photo right shows variable depth, propeller drive shaft support barrels protected externally against water corrosion by flame spraying at the works of Deritend Electrical Services, a member of the Deritend Group, St Richard's House, Victoria Square, Droitwich, Worcestershire WR9 8DS.

Tribological problems, in common with most other technological problems, are normally solved by one of two methods—1. By the application of existing knowledge. 2. By a research and development programme. The first method, on grounds of speed and economy, is usually the first to be tried and requires the means of characterizing the friction, wear, or lubrication problem, a broad knowledge of the possible alternative solutions and the necessary experience to identify the most cost effective solution. Where no technically satisfactory solution exists or where the solution is economically unattractive, a more basic approach is necessary. Although it can be said that a change of design can have the greatest influence on tribological problems in many instances constraints on change will only permit materials or lubricant substitution or possibly the application of a surface coating. In these instances the tribological problem becomes one of materials development. Examples of the solution of tribological problems by both methods are presented in this paper. They are taken from work recently carried out or presently in progress at the Fulmer Research Institute.

Articles elsewhere in this issue survey the main types of plastics coatings and processes used for protecting steel against corrosion. As a result of the introduction of these an industry of considerable size has now grown up, composed of firms specialising in the application of plastics coatings both in the factory and in the field. In the following pages we report the activities of a number of such firms, drawing attention to any new developments in products, equipment and techniques, and giving examples of work undertaken by them.

Metabrasive hosts foundry executives The Bilston based steel shot and grit manufacturers, Metabrasive Ltd, played host to a party of senior foundry executives from the Southern England and West Midlands Branches of the British Foundry Association (BFA) last month. The party was led by Mr. Norman Gledhill, the newly appointed director of the Association, and included Mr. W. M. Sutherland, chief executive of METCON which represents a group of trade associations including BFA, in areas of trade affairs, labour relations and training.

Refractory Coatings. A new range of refractory protective coatings is being manufactured under the name of Coltrate R.P.C. There are several types to deal with varying conditions, and they are all supplied in the form of a dry powder. To prepare for use, the powder is mixed with water to a thick, creamy paste and applied by brushing, spraying or trowelling to give a coating thickness of 1/16 in. to ⅛ in. After application, the furnace is fired and the temperature steadily increased up to the point where vitrification is reached.

Of the three available metal‐spraying techniques, only the powder and wire processes need be considered as practicable methods for combating corrosion. The third technique using molten metal requires elaborate equipment and is now only important as a means of producing metal powders. A metallising pistol is a device for passing metal in the form of powder or wire through the centre of an oxy/fuel gas flame, where it is melted, picked up by a stream of air at high velocity and propelled on to a suitably prepared surface to form a coating. The powder and wire guns produced by the Schori division of F.W. Berk & Co. represent a fair selection of the equipment used in the metal‐spraying process.

Corrosion of metal by wood — new BRE digest. The present state of knowledge on the corrosion of metal by wood is summarised in a new Building Research Establishment Digest just published. Wood and metal are used together in a myriad of applications in construction, packaging and furniture. Generally no problems of corrosion of the metal would be expected but sometimes, particularly where conditions are damp for long periods, care must be taken in the choice of components to ensure a trouble‐free life for the assembly. The risk of corrosion may also be increased if certain preservative or flame retardant treatments are to be used.