Characterization, nanomechanical, and wear attributes of sintered Al–TiB2 composites

Abstract

Herein, Al–TiB2 composites ranging from 2 to 8 wt.% TiB2 addition developed through a Turbula mixer and fast-assisted sintering technology were investigated. The distinct phases and morphologies of the fabricated compacts were assessed via the X-ray diffractometer and scanning electron microscope. The mechanical and wear properties of the fabricated compacts were evaluated. The dispersal of TiB2 particles and the formation of an interface phase were noticed on the microstructure of the fabricated specimens. The diffractogram confirmed the presence of the TiB2 phase and Al5Ti3 phase at the plane (002), corresponding to the 2-theta value of 44.9°. The relative density of the fabricated specimens indicated an average of 99.33%, while the microhardness values were in the range of 33.1–41.3 HV1. Adding the TiB2 particle to the Al matrix raised the tensile strength value to 140 MPa on account of good dispersion of the TiB2 particle restricting the dislocation movement in the composites, further strengthening the Al–TiB2 composites at the cost of its ductility. The nanoindentation values (elastic modulus and hardness) of the fabricated Al–TiB2 composites improved compared to the fabricated Al matrix. TiB2 improved the wear properties of the fabricated Al–TiB2 composites by lowering it. Delamination, oxidation, and adhesion wear mechanisms are the noticeable wear observed from the fabricated Al–TiB2 composites. The image of the fractured Al–TiB2 composites depicts dimples and microvoids, which are the characteristics of ductile fractures.