Hardness and fatigue behavior of SiC, Al2O3, and blast furnace slag reinforced hybrid composites with Al6061 matrix

Abstract

This study aims the use of blast furnace slag, produced as waste during the production of raw iron in blast furnaces, as a reinforcing element in the production of metal matrix composites. The Al6061 alloy, widely used in the automotive industry, was chosen as the matrix. SiC and Al2O3, two commercial ceramics frequently used in MMC production, were used as the second and third reinforcing elements in hybrid composite production, and their compatibility with blast furnace slag was investigated. Composites were produced using the stir-casting method with reinforcements sized between 22 and 59 mu m. Microstructure examinations revealed the presence of blast furnace slag within the internal structure, a homogeneous distribution of reinforcing elements, and the absence of agglomeration. Brinell hardness measurements determined that a 5 wt.% addition of blast furnace slag increased the hardness of the Al6061 alloy by 29.31 %. The greatest increase in hardness, 108.62 %, was observed in the hybrid composite containing 3 wt.% Al2O3, 3 wt.% SiC, and 5 wt.% BFS reinforcements. Fatigue life tests indicated that fatigue life improved with increasing reinforcement. The most significant enhancement in fatigue life, 625.28 %, was observed in the composite reinforced with 3 wt.% BFS, 5 wt.% Al2O3, and 5 wt.% SiC compared to the unreinforced alloy.