In this study, fabrication of multilayer Al(Zn)-Al2O3 with different volume fractions of Al2O3 were investigated. In this regard, Al and ZnO powders were milled by a planetary ball mill and then five-layer functionally graded samples were produced using hot pressing at 580 ºC under 90 MPa pressure for 30 min. Formation of Al2O3 reinforcing particles was occurred in aluminum matrix by aluminothermic reaction. Determination of ignition temperature of the aluminothermic reaction was accomplished using differential thermal analysis and thermo gravimetric analysis. Scanning electron microscopy, energy dispersive spectroscopy and X-ray diffractometery analysis were utilized to characterize the specimens. The thermal analysis results showed that ignition temperatures of aluminothermic reaction for the layers with highest and lowest ZnO content were 667 ºC and 670 ºC, respectively. Microstructural observation and chemical analysis confirmed the fabrication of Al(Zn)-Al2O3 FGM composite with precipitation of additional Zn in the matrix. Moreover, maximum and minimum hardness values of nearly dense functionally graded sample were obtained as 75 and 130 Hv, respectively.

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