Aluminium alloy rounds - with low beryllium content for guaranteed surface oxide film thickness

摘要

The rounds are of Al alloy of compsn. 2-4% Mg, 0.2-0.3% Mn, bal Al and are initially formed from material contg. is not 0.00003% Be. Used for multistage drawing to hollow cylinders, e.g. spinning bobbins, and an oxide layer, acting as lubricant support, of 0.006-0.010 mm thickness can be guaranteed after annealing.