The Forming of Aluminium‐Alloy Sheet

THE fundamental principles underlying the heat treatment and manipulation of aluminium alloys of high strength and quality are widely known in the aircraft industry. They have been used as bases on which a comprehensive system of official specifications and technical instructions have been built. Nevertheless, the rapid evolution of the all‐light‐alloy aeroplane, allied to the vast increase in output owing to the war, results at times in a tendency to ignore the fact that working ranges with the materials are such as to demand close observance of a number of essential precautions if failures during treatment and forming are to be avoided. The following notes have been compiled with a view to indicating some frequently‐ignored, but important, points which must be taken into account in the forming of high‐strength aluminium‐alloy sheet to the profiles required in stressed aircraft components.