Production and Characterization of Hypoeutectic Al-Si Matrix Composite Reinforced with Metallic Glass Particles

In the present study, an aluminum-silicon hypoeutectic alloy matrix composite reinforced with metallic glass particles was produced through Powder Metallurgy (PM) method. In the first step, the synthesized matrix powder particles with Al-11wt%Si composition were mixed with Fe-based Metallic Glass (FMG) particles as the reinforcements. In the next step, Spark Plasma Sintering (SPS) method was employed to produce composite bulk parts. For comparison, pure aluminum powder particles were sintered under the same conditions. The phase studies confirmed some alterations in the intensity and diffraction angle of crystalline peaks for the composite compared to pure aluminum. Moreover, they remarked a change in the location of the amorphous hump in the XRD pattern of composite, compared to its former location in the amorphous powder particles. Further analysis of the XRD patterns proved the solubility of a large portion of silicon in the aluminum. Microstructural studies, along with quantitative analysis, indicated the homogenous distribution of the FMG particles and undissolved silicon particles in the aluminum matrix. The yield and compressive strength values of the composite sample were obtained as 165 and 289 MPa, respectively, showing a significant increase compared to the pure aluminum sample. Finally, the contributions of different strengthening mechanisms to the enhancement of the composite strength was elaborated