Development and Characterization of In Situ AlSi5Cu3/TiB2 Composites

The present investigation focuses on improvement in mechanical properties of AlSi5Cu3 aluminum alloy by in situ synthesis of TiB 2 reinforcement particles. Stochiometrically calculated amount of potassium tetrafluoro borate and potassium hexafluoro titanate were used for the development of 3 and 6 wt% particles of TiB 2 in the liquid metal. The melt having TiB 2 particles was allowed to solidify naturally in the sand mold. X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed the formation of hexagonal TiB 2 particles within the matrix. Microstructural studies concluded the formation of micron size TiB 2 particles and reduction in grain size. Ultimate tensile strength increased from 21 to 64% and hardness increased from 30 to 50% compared to AlSi5Cu3 alloy due to the formation of 3% and 6% TiB 2 particles, respectively.