Investigation of Microstructural, Mechanical and Corrosion Properties of AA7010-TiB2 in-situ Metal Matrix Composite

Abstract

Aluminum alloys with ceramic reinforced particulates are made prospective in aerospace, transportation, and industrial applications ampler to their low mass density, stiffness, and high specific strength. In this work, Aluminium Alloy(AA) 7010 - TiB2 (Titanium Diboride) composites with different amounts of reinforcement (5, 7.5 and 10 wt.%) were produced by the exothermic reaction of halide salts K2TiF6 and KBF4 added in 120% excess to the stoichiometric ratio with molten AA7010.The effect and dispersion of TiB2 particulates in AA7010 were analyzed by microstructural, mechanical and corrosion behavior. The dispersion of reinforcement in the matrix alloy was analyzed by optical microscope and field emission scanning electron microscope (FESEM) images. X-ray diffraction patterns of the prepared composites reveal the formation of TiB2 particles in the matrix alloy. Indeed samples are tested according to ASTM G34 standard for ex- foliation corrosion rate by weight loss method. The result shows improved hardness, tensile strength and yield strength of composites to about 35%, 260%, and 240% respectively. The mechanical and corrosion resistance of 10% TiB2 shows better results compared with matrix alloy and other concentrations of reinforcements.

Keywords

• aa7010
• tib2
• stir-casting method
• exfoliation corrosion test