Fabrication and effect of milling time on spark plasma sintered Ti6Al4V/Gr Composite

Titanium metal matrix has been extraordinary in engineering applications due to their unique thermo-mechanical properties. With these features, the manner of fabricating them has played a significant part in improving their properties by incorporating titanium metal matrix with other materials. However, Spark plasma sintering (SPS) has appeared as a feasible route to produce this composite owing to its short sintering cycles and ability to limit grain growth. In this investigation, the effect of milling time on sintered composite was evaluated. Titanium metal matrix (Ti6Al4V) was reinforced with graphite (Gr) content (2 wt. %) by high energy ball milling (HEBM). The powder mixtures were consolidated by SPS at the sintering temperature of 1000 oC, pressure of 50 MPa, heating rate of 100 oC/min and holding time of 5 min. Scanning electron microscopy (SEM) was used to study the microstructural evolutions of the sintered samples and XRD (X-ray diffractometer) was used to identify the phase changes in the composites. The resulting mechanical properties revealed that the densification of the composites increases with graphite content and milling time from 5 to 10 hours.