Particulate Reinforced Aluminum Matrix Composites Obtained By Indirect Squeeze-Casting 91A115

Indirect squeeze casting technology is one of the most attractive fabrication techniques of near net shape components constituted by aluminum matrix composite (AMC) materials.

AMCs reinforced with both continuous and discontinuous ceramic elements have been mainly produced by infiltration of porous preforms. Nevertheless, a further promising production route offered by this technique is given by the possibility to employ ingots of pre-reinforced aluminum alloys containing ceramic particles (silicon carbide or alumina); ingots are remelted and, under suitable operative conditions, high quality composite castings of simple and complex shape are produced by squeeze casting.

The present paper describes the results of an extensive experimental work carried out by Alures-Centro Tecnico Porcessi on a pilot plant scale employing a vertical squeeze casting machine with a clamping force of 315 tons. The conditions of use of the reinforced material in the melt state and the main casting process parameters are discussed; experimental results of both mechanical and physico/chemical characterization of the staff composite material (A356 aluminum matrix alloy reinforced with SiC particles) produced by this technique are presented.

Particulate reinforced squeeze cast components produced by this route have wide possibilities of employment in several industrial fields: the most relevant applications, and in particular those in the automotive sector, are discussed in the paper.

Some examples of prototipal components produced by Alures, employing the described materials and technology, are shown.