Mechanical and Tribological Properties of Al/n-Al2O3 Composites Processed by Combined Stir-Ultrasonic-Squeeze Casting
摘要
Alumina nanoparticles (n-Al2O3) being a hard refractory ceramic material is extremely suitable for structural and high temperature applications due to its superior strength and low thermal coefficient of expansion. The present study focusses on the development of Al2014/n-Al2O3 reinforced metal matrix composites utilizing combined stir, ultrasonic and squeeze casting method. Combination of the three different techniques during casting have aided in achieving very low porosity of the resulting composites. Composition of the hybrid composites is varied by utilizing different quantities of dispersed n-Al2O3. The as-received raw materials and processed composites are characterized by standard available techniques to study the phase, morphology, and distribution of the reinforced phases in the matrix. Assessment of the mechanical properties exhibit improvement in the hardness and tensile strength of the composites in comparison to Al2014. Tribological properties of the developed composites have been investigated to study the effect of the reinforcement and applied load on the wear and coefficient of friction. Post tribology worn surface characterization reveals the mechanism of wear of the composites.