An evaluation of tribological and mechanical properties of Al-Si-Cu alloy with nano-clay particles reinforcement

Abstract

In this paper, comparative evaluations on the mechanical properties of Al-Si-Cu alloy reinforced by nano-clay mineral particles were carried out. Such nano-composites contained 1 wt% nano-clay particles and were manufactured through the stir casting with various stirring temperatures and times. Mechanical behaviors such as the hardness and compressive strengths, the elastic modulus and wear properties were studied. The microstructural observations were conducted by the optical and the scanning electron microscopy. Field emission scanning electron microscopy (FESEM) images showed that nano-clay particles distributed uniformly in the aluminum matrix for the nano-composite fabricated at 800 ℃ and was stirred for 2 min. Besides, the lower stirring temperature of 750 ℃ caused a degree of clustering with a size of lower than 200 nm in some places. In comparison with the base alloy, an improvement of 5% to 33% in Brinell hardness value observed for various nano-composites. The wear resistance of various nano-composites also increased two to five times regarding the base alloy. The parameter of µ/E. H2 would predict the wear rate for all specimens. It was found that nano-composites fabricated at the temperature of 750 ℃ exhibited the lower porosity content and the higher ultimate compressive strength, and the elastic modulus.