Features of the Processing of AA2124 Aluminum Alloy Metal Matrix Composites Reinforced by Silicon Nitride Prepared by Powder Metallurgy Techniques

Abstract

Powder Metallurgy (PM) Techniques consists in a suitable technique to process composites materials. A specific PM technique of mechanical alloying developed to produce new materials in the solid state is a well known route to obtain aluminum alloys metal matrix composites. Aluminum alloys metal matrix composites allies the good properties of aluminum and its alloys but with poor mechanical properties and the reinforcement of ceramics phases which add better mechanical properties to these alloys. The research of this materials processing by PM techniques presented new materials with improved properties. In this work an AA2124 aluminum alloy was reforced by particulated silicon nitride a kind of ceramic phase. The powders were mixed and then processed by mechanical alloying in a SPEX vibratory type mill. Then the powders obtained were compacted and vacuum sintered. The sintered composites were characterized by means of Scanning Electron Microscopy (SEM) plus Energy Dispersive Spectroscopy (EDS) and Vickers hardness tests to evaluate the mechanical behavior.