Study of the addition of silicon carbide on the metallurgical and mechanical properties of an aluminum-copper alloy

ABSTRACT

The obtainment of composite materials is of great interest for the automotive and aerospace industries. This study aims to obtain through powder metallurgy the Al-4,5Cu composite reinforced with additions of 5%, 10% and 15% of silicon carbide particles. The elemental powders were analyzed by Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). To determine the compressive stress, compressibility tests were used, and a load of 200 MPa was adopted. The sintering atmosphere was high purity nitrogen at an isotherm of 590ºC for 90 minutes. For microstructural characterization Optical Microscopy (OM) and scanning electron microscopy (SEM) techniques were used. The polymorphic behavior was evaluated by X-Ray Diffraction (XRD) technique and the microhardness evaluated by Vickers method (HV_0,1). The results demonstrated the diffusion of copper in the aluminum matrix forming the intermetallic Al₂Cu. The addition of silicon carbide did not affect significantly the formation of the composite. An increase in microhardness was detected for additions above 10% of SiC. It is concluded that there is feasibility of obtaining components with composite alloys of aluminum, copper and silicon carbide via powder metallurgy.

Keywords
Sintering; Al-Cu Alloy; Composite; Silicon Carbide; SiC