Solidification observations and sliding wear behavior of vacuum arc melting processed Ni–Al–TiC composites

Monolithic Ni3Al and Ni–25at.%Al intermetallic matrix TiC-reinforced composites were successfully produced by vacuum arc melting. TiC crystals were formed through a dissolution–reprecipitation mechanism and their final morphology is explained by means of a) Jackson's classical nucleation and growth phenomena and b) solidification rate considerations. The TiC presence altered the matrix microconstituents most likely due to specific melt–particle interactions and crystal plane epitaxial matching. TiC particles caused a significant decrease on the specific wear rate of the monolithic Ni3Al alloy and the possible wear mechanisms are approached by means of a) surface oxidation, b) crack/flaws formation, c) material detachment and d) debris–counter surfaces interactions. ► Vacuum arc melting (VAM) of Ni-Al based intermetallic matrix composite materials. ► Solidification phenomena examination. ► TiC crystal formation and growth mechanisms. ► Sliding wear examination.