LAUSR

Abstract In this research work, the new kind of 6111Al matrix composites reinforced by nanosized ZrB2 particles and rare earth element Y have been successfully prepared via the Al-KBF4-K2ZrF6-Y in situ reaction system in the melt. Compared to the traditional particle reinforced aluminum matrix composite, this innovative fabrication system broke through the limit in the content of reinforcing phases and helped to modify the morphology and distribution of in situ ZrB2 particles with assistance of Y addition. The results of tensile testing on 6111Al-3 wt%ZrB2-0.3 wt%Y composites revealed that the YS, UTS and elongation reached to 295 MPa, 325 MPa and 13.2%, which have been increased by 28.2%, 19.5% and 83.3% respectively compared to the matrix alloy. The distribution state and morphology of reinforcing phases including in situ ZrB2 particles, Al3Y and Y5Si3 precipitates were analyzed by the latest equipments like X-ray diffraction (XRD), Optical microscope (OM), Scanning electron microscope (SEM) and High resolution transmission electron microscope (HRTEM) equipped with Energy dispersive spectroscope (EDS).