Tribological behaviour and wear fashion of processed AA6061/ZrO₂ composite

Abstract

Purpose This study aims to develop a less weight high wear resistant material to fabricate brake components especially in automotive sector. Design/methodology/approach Effort was initiated to design and develop aluminium metal matrix composite by combining aluminium alloy AA6061 and zirconium oxide (ZrO2) with the help of stir casting coupled with squeeze casting unit. Morphology analysis of advanced composite has been carried out by optical microscopy and scanning electron microscopy (SEM). The hardness of composites having different compositions was tested using Vickers micro hardness tester. The tribological property of the developed three specimens having different composition has been tested using pin-on-disc wear test equipment under dry sliding conditions. To obtain better understanding of wear mechanism, SEM image of worn-out surface was captured and analysed. SEM images and the corresponding Energy-dispersive X-ray spectroscopy (EDX) on the wear surface were carried out. Findings The optical and SEM images evidenced the existence of ZrO2 particles along the metal matrix composite. Porosity values shows that the porosity level is acceptable as it falls below 7 per cent. Also, the finding proves that increase in the percentage of reinforcement particle instigates agglomeration on the AA6061 composites. Hardness test demonstrated that the inclusion of hard ZrO2 particles leads to substantial improvement in hardness and the hardness value started deteriorating when the composition reaches 15 per cent. The wear test results substantiated the enhancement of tribological property due to the inclusion of distinct ZrO2 particles. Also, despite of addition of reinforcements, the wear rate increased when the load increases. SEM images proved that AA6061/ZrO2-5 per cent composite fashioned steady-state mild and smooth wear. EDX spectrum analysis revealed the existence of ZrO2 particles along with wear debris, which caused wear of 685 µm in AA6061/ZrO2-15 per cent composite. Originality/value The developed material possesses low wear rate which is the unique property of composite and frictional force which is directly proportional to load but the coefficient of friction remains apparently constant. As a whole, investigations on developed composites introduce a new material which is suitable for manufacturing of brake components for automobile industry.

A study on tribological behaviour and analysis of ZnO reinforced AA6061 matrix composites fabricated by stir casting route

“…Thus, the wear rate values are decreased when ZnO weight percentage increases. Similar kind of observation was reported by Velmurugan et al (2012) and James and Annamalai (2018).…”

“…The results clearly indicate that when reinforcement increases, both theoretical and experimental density also increased. As the porosity level was within 7%, the composite may be acceptable (James and Annamalai, 2018). The increase in porosity and the difference in density were because of the addition of ZnO microparticles with the AA6061 matrix.…”

Sliding wear response of ultrasonic-assisted stir-squeeze cast Al-Zn(-Mg) alloy/ZrO2p composite: wear mechanism and subsurface deformation

“…Beyond a critical load, a severe wear regime was observed by Zhang et al [18], resulting in considerable surface degradation and material transfer to the counter disc. James et al [19] noticed a static mild and smooth type of wear regime in AA6061 composite containing 5% ZrO 2p , and with increasing the ZrO 2p concentration to 15%, some agglomerated cites were evident, which in due course resulted in deep ploughing, grooving, and delamination type of severe wear. Ramchandra et al [20] observed oxidation, micro-cutting, and thermal softening operative wear mechanisms.…”

Wear Behaviour Analysis of Heat Treated A356 Composite with Copper and Copper-Coated Zinc as Reinforcements

“…Aluminum alloys have gained significant popularity across various industries in recent times due to their exceptional characteristics, such as lightweight, high strength-to-weight ratio, good conductivity, malleability, high heat conductivity, and excellent corrosion resistance [1][2][3] . The aerospace and automotive industries find aluminum alloys to be a desirable option for numerous applications because of their lightweight nature, which is crucial for ensuring durable structures 4,5 . The popularity of aluminum alloys is expected to continue to grow as more industries discover their many benefits and as new manufacturing processes are developed to make them even more cost-effective and sustainable.…”