CT COMMENTARY

B.I.S.R.A. AT WORK. Good progress is reported on the development by the British Iron and Steel Research Association of a process for coating steel strip with aluminium powder by electrophoretic deposition followed by rolling and heat treatment. The Association's annual report for 1960 states that a 5‐in. experimental line is being constructed at Sketty Hall, Swansea, to produce the new material, known as Elphal. It is said there is very little alloy present and that porosity is so low that the surface can be anodised. PVC‐coated steel is also occupying much of B.I.S.R.A.'s attention. Efforts so far have been mainly directed towards evolving a cheap, pore‐free coating on thin strip. It was decided to use PVC powder as this is the cheapest form of PVC and has the additional advantage of allowing curing of the adhesive and gelling of the plastic in one operation. A very high‐speed compact plant (perhaps 500 ft./min.) was envisaged. Developments in the direct calendering operation have now enabled the experimental plant to be operated at its full speed of 30 ft./min. and steps are now being taken to increase the maximum speed.