Colorimetric determination of copper in aluminium alloys

Abstract

A very rapid method for the colorimetric determination of copper in aluminium alloys is described. The sample is dissolved in hydrochloric and nitric acids, and an excess of ammonia is added to precipitate the aluminium, iron and silica. The solution is diluted to 500 ml. and a portion is filtered and read with a colorimeter at 580 m μ. A small correction is necessary for samples containing nickel.