Abstract:The cenosphere dispersed Ti matrix composite was fabricated by powder metallurgy route, and its wear and corrosion behaviors were investigated. The results show that the microstructure of the fabricated composite consists of dispersion of hollow cenosphere particles in α-Ti matrix. The average pore diameter varies from 50 to 150 μm. The presence of porosities is attributed to the damage of cenosphere particles due to the application of load during compaction as well as to the hollow nature of cenospheres. A detailed X-ray diffraction profile of the composites shows the presence of Al₂O₃, SiO₂, TiO₂ and α-Ti. The average microhardness of the composite (matrix) varies from HV 1100 to HV 1800 as compared with HV 240 of the as-received substrate. Wear studies show a significant enhancement in wear resistance against hardened steel ball and WC ball compared with that of commercially available Ti-6Al-4V alloy. The wear mechanism was established and presented in detail. The corrosion behavior of the composites in 3.56% NaCl (mass fraction) solution shows that corrosion potential (φ_corr) shifts towards nobler direction with improvement in pitting corrosion resistance. However, corrosion rate of the cenosphere dispersed Ti matrix composite increases compared with that of the commercially available Ti-6Al-4V alloy.

Key words: Ti matrix composite; sintering; wear property; corrosion; microstructure