Degassing of Aluminium & Its Alloys

Abstract

This article describes various reagents and the techniques employed for degassing molten aluminium and its alloys. The sources of gas pick up and the consequent adverse effects on the properties of the alloys have been discussed . The limitations of degassing by vacuum, ultrasonic, chloride flux treatments , etc., of the melt have been mentioned . Recent developments in the use of chlorine - nitrogen - carbon monoxide mixture and dispersion of uniform gas bubbles through non - reactive porous ceramic bricks for effective degassing are incorporated. A comparison of different types of degassers in terms of efficiency of gas removal, toxicity and economics is given.