Microstructure of diamond/aluminum composites fabricated by pressureless metal infiltration

In this work, morphology and interfacial characteristics of aluminum matrix composites reinforced with diamond fiber were studied. Samples were fabricated by pressureless metal infiltration process and its thermal conductivity reach as high as 518 W/m K, while its thermal expansion coefficient exhibited as low as 4.61 × 10−6/K. The obtained composites were investigated by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and element map techniques. The diamond fiber was homogeneously dispersed and well bonded inside the aluminum matrix. It was found that silicon and magnesium were aggraded around the interface. Moreover, aluminum carbide phases (Al4C3) were randomly formed between aluminum matrix and diamond fiber.