Journal of King Saud University: Engineering Sciences (Jul 2020)
Ceramic nanofibers versus carbon nanofibers as a reinforcement for magnesium metal matrix to improve the mechanical properties
Abstract
Light composite materials based on Magnesium matrix reinforced with carbon or ceramic nanofibers were fabricated by powder metallurgy rout using high frequency induction heat sintering (HFIHS) technique. A comprehensive comparative study has been investigated on using ceramic nanofibers and carbon nanofibers as a fibers reinforced Magnesium metal matrix in order to evaluate the overall improvements in mechanical properties. Electrospinning technique followed by calcination process were used efficaciously to synthesize and fabricate the Titanium Oxide (TiO2) fibers and carbon fibers. Mg/nanofibers mixtures were prepared via powder metallurgy route using mechanical alloying technique by adding 1, 3, 5 and 10 wt% calcined nanofibers to Mg matrix. In inert atmosphere and room temperature, mixtures were initially processed using high energy ball milling for 15 + 15 min. The final bulk cylindrical samples were obtained by performing consolidation or sintering process using high frequency induction heat sintering furnace (HFIHS). Characterization of the sintered composites have been investigated using field emission scanning electron microscopes (FESEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). While, hardness test and compression test were performed in order to evaluate the mechanical properties of the fabricated composites. The obtained result shows that, the ultimate compressive strength increased to 281 MPa at 5 wt% TiO2, which represent about 12.4% more than the pure Mg. Hardness improved up to 64.4% in case of using the ceramic nanofibers as reinforcement. While using CNFs as reinforcement to the Mg matrix, slightly deteriorates the mechanical properties.