Fibre/matrix intermetallic phase formation in novel aluminium-basalt composites

Abstract

A novel aluminium-basalt metal matrix composite has been produced by employing a combination of stir mixing and ultrasonication processing techniques. A study of the matrix-fibre interface has revealed the formation of Al-Si-Ca and Al-Fe-Si-Mn intermetallic compounds (IMC) with both phases displaying a polyhedral morphology. The new composite exhibited a tensile strength of 189 MPa, resulting in a 13 % improvement over the monolithic Al alloy. A 22% increase in yield strength and a 33% increase in wear resistance were also achieved, although the flexural and elastic moduli remained unchanged. It is proposed that these IMCs assist in load transfer from the matrix to the fibres.