Mechanical and microstructural characterization of AA7178-TiB2 composites
V. Mohanavel
Abstract
Abstract In the present investigation, an aluminum alloy AA7178 was reinforced with three different weight fractions (3, 6 and 9 wt.-%) of titanium diboride (TiB 2 ) particles which were efficaciously synthesized through exothermic reaction of halide salts such as potassium hexafluoro-titanate (K 2 TiF 6 ) and potassium tetrafluoro-borate (KBF 4 ), with molten aluminum melt to bring out unique properties. In-situ reaction between the halide salts, e. g., K 2 TiF 6 and KBF 4 in molten aluminum leads to the formation of TiB 2 particles. The synthesized final composites were characterized using X-ray diffraction (XRD) and a scanning electron microscope (SEM). The SEM micrographs indicated the even dispersion of the TiB 2 filler particle in the composites. Tensile strength, compression strength and micro-hardness of the prepared composites is measured and compared to plain matrix alloy. The manufactured composites are mechanically characterized as per the American Society for Testing and Materials (ASTM) standards, employing a computerized universal testing machine. The mechanical properties of the composite were discovered to be obviously superior to those of the basic matrix alloy owing to augmented particle content.