Abstract

The Al-Si alloys used in this investigation was prepared at the University of Kufa in the Metallurgy Laboratory. Heyper eutectic Al-Si alloys with compositions 15, 17, 19 wt% Si was quenched from the liquid state by using melt-spinning techniques. The as cast alloys and resulting ribbons were characterized using optical microscopy, scanning electron microscopy(SEM),X-ray diffraction (XRD) analysis, microhardness techniques and compared with their ingot alloys.Effects of chemical composition and quenching conditions on the variation in the microstructure were examined. Microstructural examinations revealed that microstructures of the melt-spun ribbons were very fine compared to their ingot alloys. The results microhardness value of the ribbons melt-spun alloy was measured as 82-200 kg/mm2 . The microhardness of as cast ingot and rapidly solidified ribbons approximately twice higher than those of original ingot alloy.