Residual stress measurements and microstructural characterization of graphite-aluminum metal matrix composite

P 100 graphite fiber reinforced aluminum metal matrix composites used in this research have residual stresses due to the difference in coefficients of thermal expansion of the components. The residual stresses which are dependent on the thermal history cannot be neglected in their magnitude. Residual stresses of the metal matrix with various thermal histories have been measured by x-ray diffraction (XRD) method and compared with the mathematical analysis. Before these measurements the XRD method was calibrated by measuring elastic properties of the monolithic 6061 aluminum plate with three-point bend fixture and comparing with those obtained by the tension test.; To better understand thermal and mechanical behaviors of P 100 Gr/6061 Al composites it is important to fully characterize the microstructures of the composites and graphite fiber-aluminum matrix interface has been observed by electron microscopy techniques.; The microstructural features which play a key role in controlling the strength of the composites were analyzed using (Scanning) Transmission Electron Microscope, with its capability for energy-dispersive spectroscopy (EDS) for elemental analysis of particles and phases. Differential scanning calorimetry (DSC) was also conducted to examine precipitation behavior of both the composite and the monolithic 6061 Al plate.