A Study of Influence of Density on Al-Cu Composition During Compaction Process

Powder metallurgy is a technology used for producing machine parts and oil-impregnated bearings from a metal powder. Highly accurate products can be efficiently mass-produced, and for that the powder metallurgy is indispensable particularly in automobile industry. Therefore powder characteristics are important because they often determine the choice of a particular processing route. In general, a mixed powder that is a metal powder is moulded by compression and the resultant green compact is then dewaxed. Subsequently, in powder metallurgy, the compact is sintered at a temperature of about 550 oC.In this sintering process, the mixed metal powder forms an alloy, thereby increasing the strength of the compact. It is done under a protective atmosphere with or without fusion of a low melting point constituent only so as to develop metallic or metal like bodies with satisfactory strength, density and without losing the essential shape [1]. A cutting operation is then performed on the resultant sintered compact. Metal powders are produced in various methods such as atomization, shotting, stamping and ball milling but pot mill is preferable. Spherical and dendritic metal powders are produced by atomization methods and flake shaped metal powders are produced by ball milling method. For the investigation purpose a quantity of copper powder is added to aluminium powder and mixed well by using pot mill to get homogeneous mixture. The aim of this paper is to establish the correlation among flow rate, compaction and sintering process and densities of compact of 3 % of Cu in Al.