Micro-yield behaviors of Al2-O3-SiO2(sf)/Al-Si metal matrix composites

Effects of the volume fraction and the size of crystallized alumina silicate short fibers as well as heat treatment processes on micro-yield strength(MYS) of Al2-O3-SiO2(sf)/Al-Si metal matrix composite(MMC) that was fabricated by squeezing cast, were investigated by using continuous loading method on an Instron 5569 tester with a special extensometer with an accuracy of 10−7. The results show that MYS of MMC decreases with the increase of volume fraction and length of the alumina silicate short fibers in the metal matrix composite, respectively. MYS of quenched Al2-O3-SiO2(sf)/Al-Si MMC is the lowest, MYS of the MMC through peak-aging treatment is higher than that through other heat treatment methods. And before the peak-aging, MYS of MMC aging treated gradually increases with the increase of the aging time. Aging treatment after solution treatment is a preferred way that enhances micro and macro-yield strength of Al2-O3-SiO2(sf)/Al-Si MMC.