Caracterización de un material compuesto de matriz aleación de aluminio-silicio reforzada con partículas de carburo de silicio

Abstract

This project aims at characterize an aluminium-silicon alloy matrix composite reinforced with silicon carbide particles. For this, low density composites were obtained from a matrix alloy Al-Si 365.0 and a ceramic reinforcement of SiC mesh #400, obtaining a combination of properties required by the automotive industry to reduce fuel consumption. For the 365.0 alloy, a cylinders block of a Honda automobile was used, selected from the ANSI 3xx.x series. SiC is a particulate powder, selected from ceramics of Al2O3, B4C, TiC. A stir casting equipment was built for the preliminaries tests of the dispersion of SiC particles in the melted matrix 365.0. In addition, a fabrication process of ingots was developed by stir casting with gravitational pouring in a binder sand mold, obtaining composites 365.0/SiC/2p (2%SiC), 365.0/SiC/4p (4%SiC), 365.0/SiC/6p (6%SiC). By melting the block the matrix 365.0 was obtained. From these materials, under ASTM Standard, specimens were prepared for tensile, hardness and microscopy tests. The 365.0, 365.0/SiC/2p, 365.0/SiC/4p y 365.0/SiC/6p specimens were characterized, obtaining values of strength [MPa]-hardness [HBW] of 108-46, 101-52, 119-56 and 131-58, respectively, concluding that the increase of the percentage of SiC in the matrix 365.0 the strength and hardness are increasing. The microstructural test shows the phases present of the composites. Finally, a composite C-365.0/SiC/6p (6%SiC) was also developed but pouring in steel mold, its strength is 217 MPa and hardness 78 HBW, presenting better properties compared to composite 365.0/SiC/6p.