Corrosion and wear behaviors of brick powder reinforced aluminum composites manufactured by stir casting

Abstract

Aluminum 6061 (Al6061) possesses good mechanical properties, strength, hardness, and corrosion resistance. However, the properties of Al6061 can be sufficiently raised by making composites. Metal matrix composites (MMCs) are well known for their high strength and corrosion resistance. However, these properties depend on the reinforcement materials added to the metal matrix. In the present work, Al6061-based MMCs have been manufactured by stir casting. In these MMCs, brick powders are used as reinforcement materials. Four MMCs have been developed by varying concentration and size of brick powders: MMC1, 2 h ball milled and 1% by weight; MMC2, 2 h ball milled and 7% by weight; MMC3, 4 h ball milled and 1% by weight; and MMC4, 4 h ball milled and 7% by weight. The successful formation of MMCs is examined by field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray powder diffraction. The corrosion and wear resistance of the manufactured MMCs have been investigated by electrochemical measurements and a pin-on disc tribometer. Based on the results of both tests, MMCs can be ranked as MMC4 > MMC3 > MMC2 > MMC1. The reason for improved behavior can be quoted as an enhancement in overall hardness and interaction of reinforced material with the matrix. To support this statement, the Vickers hardness of Al6061 and the developed composites have also been measured.