Production and characterisation of aluminium matrix titaniumdiboride reinforced in situ composites

Aluminium matrix composites are widely used owing to its higher mechanical properties as specific strength, hardness and wear resistance. Wetting between matrix and reinforcement and homogenous distribution of particulates in the matrix are the main problems that occur during the fabrication of aluminium matrix composites. Reinforcement particulates are constituted in molten metal by various chemical reactions during the fabrication of in-situ composites. Thus, in-situ composites can be fabricated with both lower particulate dimension and homogenous distribution. In this study, aluminium matrix TiB2 reinforced in-situ composite fabrication was investigated. For this purpose, A356 aluminium alloy was chosen as matrix material and K2TiF6 / KBF4 salts were used for constitution of TiB2 particulates in molten metal. A356 alloy was melt at 800˚C and 850˚C, K2TiF6 / KBF4 salts are mixed in molten metal to obtain 2.5% and 5% reinforcement ratio. Specimens were characterized by microstructural analysis, and also hardness, wear and corrosion tests.