Influence of zrb2 particles on the mechanical and tribological properties of aa6082 alloy

Abstract

The present research work is focussed on developing a novel composite material through liquid metallurgy route. The matrix material is AA6082 reinforced with ZrB2. The particle size of the reinforcement is 40 and#956;m. The composites were fabricated in stir casting setup in the following compositions AA6082, AA6082-3wt% ZrB2, AA6082-6wt% ZrB2 and AA6082-9wt% of ZrB2. The composites developed were tested for tensile strength, compressive strength, Flexural strength, Micro and macro-hardness and wear on pin on disc. The microstructure characterization is studied with the micrographs taken through SEM and chemical composition through XRD. The AA6082 alloy rod was chopped into little pieces, taken in a graphite clay crucible and melted in an electric resistant furnace at a normal temperature of 850oC. A determined quantity of preheated (400oC) ZrB2 content was included to the molten Al alloy and stirred appropriately to attain even distribution. The molten alloy is then poured into the square shape metal mould (100 mm x 100 mm x 10mm). The similar route is replicated to fabricate several mass fractions (3, 6 and 9 wt. %) of reinforcement composite materials. The Mechanical properties of the developed composite material for various compositions were tested for tensile strength, compressive strength and hardness. The effects of ZrB2 on the mechanical properties were studied in detail. To study the interfacial bonding between the matrix and the reinforcement microstructure characterization is done. A microstructure assessment was carried out on properly polished and etched samples of both AA6082 matrix and manufactured composites. Keller s reagent was employed as an etchant. The etched samples were examined under a scanning electron microscope (SEM) and X-ray diffractometer (XRD). The flexural strength of the AA6082 alloy and the produced AMCs samples were defined employing a fully computerized universal testing machine. The flexural test samples with a size of 80 x 11 x 20 mm3 were assessed with a loading rate of 1.0 mm/min