학술논문

Rheo-Die-Casting of Al-Si-Mg Alloy and Al-Si-Mg/ SiCp Composites: Microstructure and Wear Behavior
Document Type
article
Source
Materials Research. January 2020 23(2)
Subject
Aluminum alloy
composites
semisolid processing
microstructure
mechanical properties
Language
English
ISSN
1516-1439
Abstract
In this paper, Rheo-Die Cast (RDC) Al-Si alloy with 7.5 wt % Si and 0.3 wt %Mg and Metal Matrix Composites (MMC’s) of RDC Al-Si composites with 5 to 20 vol. % of SiCp were produced by an in-house fabricated RDC machine. Microstructure and wear behavior of both RDC alloy and composites were investigated. Results indicated that the RDC samples have significantly refined microstructure with fine and uniform non-dendritic grains resulting increased hardness and enhanced wear resistance. Wear resistance is three times higher for sample with 20% SiCp than those without SiCp additions. Surfaces of wear test samples were investigated by SEM to study the effect of both grain structure and SiCp particulates on the wear mechanism. It was also observed that reinforced RDC samples showed improved hardness and wear resistance due to the presence of SiCp in the matrix of non-dendritic grains, obtained without modification treatment.