Processing and Properties of Aluminium Based Composites Reinforced with in- situ TiB_2 Particles

摘要

The present work highlights the synthesis, processing and characterization of Aluminium based in-situ metal matrix composites (MMCs) reinforced with titanium diboride (TiB_2) particles created by an exothermic reaction of K2TiF6 and KBF4 with molten aluminium. Few aspects of AI-TiB2 composites that will be presented are: development of in-situ Al-TiB2 composites, isothermal ageing behaviour of in-situ composites, semisolid processing of A356-5wt.%TiB2 composites, equichannel angular pressing (ECAP) of Al-5wt.%TiB2 composites and "mechanical and tribological" properties of Al alloy based TiB_2 composites. It was observed that TiB_2 particles accelerate the ageing kinetics of precipitation hardenable aluminium alloys. The thixoforging of A356-5wt.%TiB_2 composites was also explored. The composites after ECAP resulted in homogenous distribution of TiB_2 particles. The mechanical and tribological properties were correlated with the microstructure of the in-situ composites.