Engineering Of Hybrid Composite/ Intermetallic Al-Fe-Si Fibers For Structural Materials Applications

Abstract:
A ternary intermetallic compound poses even greater production difficulties, since three elements have to be mixed intimately, instead of two, for the product to be uniform in chemical composition. Furthermore, the three elements must react simultaneously to prevent binary intermetallics forming by reaction between only two of the elements. This paper presents some interesting results obtained in making a ternary Al–Fe–Si intermetallic by exothermic synthesis from its elements. The production method used is a direct metal oxidation, DIMOX, technique. Liquid state processing technique is applied to generate metal matrix composite materials utilizing Al-Si-Mg alloy. Al-Si-Mg alloy is direct metal oxidized, DIMOX, in oxidizing atmosphere at different oxidizing temperatures from 750 oC to 1100 oC. The commencement of oxidized aluminum established with the formation of aluminum oxide Al2O3 at 920 oC. The effect of -Fe addition in Al-Si-Mg alloy is confirmed within aluminum solid solution as well as within alumina matrix at different ranges of oxidizing temperatures. It is shown that however the technique established with aluminum alloy reinforced with alumina, a new emerging ternary Al-Fe-Si intermetallic established in short fibers. Randomly aligned fibers, self-propagating high temperature synthesis of Al-Fe-Si intermetallic compound established in aluminum matrix as well as in alumina matrix. Exothermic reaction established close to 750 °C onset temperature for Fe powder and aluminum mixes. The effect of iron content ranging from 1 to 5 volume % dominates the occurrence of Al–Fe–Si intermetallic fibers in aluminum alloy direct oxidized at different temperatures and holding times. The results investigated in the as-cast state using scanning electricity microscope (SEM) and energy-dispersive x-ray spectroscopy (EDX). A hybrid composite established with aluminum metal matrix reinforced with alumina particulate as well as short randomly aligned intermetallic fibers.