Preparation, thermal analysis and mechanical properties of in-situ Al2O3/SiO2(p)/Al composites fabricated by using zircon tailing sand

摘要

Zircon tailing sand (comprised of SiO2 and Al2SiO5) was utilized as reinforcement precursors to prepare aluminum matrix composites (AMCs) by using indigenously developed stir casting technique. The Al2O3/SiO2(p)/Al composites were successfully fabricated at different vol.% (viz. 1.1, 3.2, 5.4, 7.5 and 9.7) of zircon tailing sand and their metallurgical and mechanical properties have been analysis. The SiO2/Al reaction in molten composites was proven by using the cooling curve thermal analysis (CCTA). Particles dispersion and wettability at SiO2/Al interface were improved with the optimized process parameters (i.e., particles preheating at 700 degrees C x 1 h, feeding rate at 10 g/min and stirring time for 10 min). Optical and SEM micrographs revealed the uniform distribution of reinforcements in the matrix. X-ray diffraction patterns and EDS testing results of the prepared AMCs revealed the presence of Al2SiO5, Al2O3, Si and the special duplex phase. The Brinell hardness, ultimate tensile strength and yield strength (sigma(0.2%)) of the composite were improved with the addition of zircon tailing sand in Al matrix. Fractured surface was carried out to explain the % elongation reduction and failure mechanism of these composites. (C) 2016 Elsevier Ltd. All rights reserved.