Dry sliding wear properties of unhybrid and hybrid Al alloy based nanocomposites

Abstract

Nanosize B₄C and/or MoS₂ particles reinforced AA2219 alloy composites were prepared using the stir casting process. The wear properties were evaluated for several speed (3.14–5.65 m s⁻¹), load (10–50 N) and distance (0–2500 m) conditions. The nanoparticles dispersion, density, wear resistance, morphology of the worn surface and loose wear debris were discussed in detail. The wear resistance improvement results by nanoparticle addition correspond well with the hardness. Between the nanocomposites, hybrid composites show significantly higher wear resistance for all load, speed and sliding distance conditions. The better wear resistance is attributed to the matrix strengthening by nanoparticles and the lubricant-rich tribolayer controlled wear in the hybrid composites. The intensity of abrasive, oxidation and delamination wear mechanisms decide the wear rate at any particular wear testing condition.

Keywords:

• Nanocomposites
• Electron microscopy
• Wear testing
• Wear mechanisms
• Stir casting
• Microstructure
• Solid lubricant
• Tribolayer

Acknowledgements

Siddesh Kumar and Shiva Shankar wish to express their gratitude to his holiness Dr. Sri Sri Shiva kumara Swamigalu president, SSES, S S Mutt. Siddesh Kumar and Shiva Shankar would like to thank Principal- Dr. Shivakumaraiah and Director- Dr. M.N. Channabasappa, Siddaganga Institute of Technology, Tumkur, Karnataka, India, for providing the facilities to carry out research work in Department of Mechanical Engineering. The first author¹ also would like to acknowledge doctoral committee member Dr. N.H. Siddalingswamy, Director, E-Governance, AICTE, New Delhi, for their suggestions on this work. The first author would like to thank the management of Siddaganga Institute of Technology, Tumkur, Karnataka, India, for financial support under World Bank Assisted TEQIP Phase-II for Research Assistantship.