Synthesis and characterization of high performance low volume fraction TiC reinforced Mg nanocomposites targeting biocompatible/structural applications

Abstract

Low volume fraction Mg–TiC nanocomposites intended for structural and biomedical applications are synthesized using disintegrated melt deposition technique followed by hot extrusion. Microstructural characterization of the nanocomposites indicates significant grain refinement of pure Mg upon addition of (0.58, 0.97 and 1.98) vol% TiC nanoparticulates with a maximum reduction of ~3% observed with 1.98vol% TiC addition. X-ray diffraction studies indicate weakening of dominating basal texture of pure magnesium with addition of (0.58 and 0.97) vol% TiC nanoparticulates. Tensile properties of the synthesized nanocomposites reveal improvement in 0.2% TYS and UTS along with significant enhancement in the tensile fracture strain of pure Mg upon nano TiC addition. The individual contributions of strengthening mechanisms such as Orowan strengthening, Hall–Petch strengthening and Forest strengthening on the tensile yield strength of Mg–TiC nanocomposites are theoretically calculated and analyzed. The tensile yield strength of the synthesized Mg–TiC nanocomposites are verified with the theoretically predicted strength values calculated using summation of strengthening contributions and modified Clyne analytical models. Compression properties of the synthesized nanocomposites reveal an increase in the 0.2% compressive yield strength of pure Mg with inappreciable effects on the ultimate compressive strength and compressive fracture strain values upon TiC nano addition. Level of anisotropy/asymmetry of pure magnesium measured using tensile compression asymmetry values of Mg (0.58 and 0.97) vol% TiC nanocomposites was found to be lower than that of the synthesized pure magnesium and a minimum of ~1 for Mg 0.97vol% TiC nanocomposite was observed.