Effect of particle size on mechanical properties and tribological behaviour of aluminium/fly ash composites

Abstract

In the present study, aluminium alloy (A380) composites containing 3, 6, 9 and 12 weight percentage of fl y ash particles were fabricated by liquid metallurgy technique. Three different size ranges of fl y ash particles (50 -75 μ m, 75 -103 μ m and 103 -150 μ m) were used. The composites were evaluated for hardness, tensile strength, density, dry sliding wear and frictional behaviour. Pin-on disc apparatus was used to conduct wear tests at loads of 20, 30 and 40 N at a sliding speed of 3 m/s for a constant period of 10 min. Results showed that hardness, ultimate tensile strength, wear resistance and coeffi cient of friction were superior in composites reinforced with coarse fl y ash particles (103 -150 μ m) compared to composites with fi ne particles. The hardness, ultimate tensile strength and wear resistance increased, whereas the coeffi cient of friction and density decreased with the increase in weight percentage of fl y ash. Wear resistance and coeffi cient of friction decreased with increase in applied load. Scanning electron microscope investigations of worn-out samples were carried out to study the progress of wear.

Tribology of Metal Matrix Composites

“…It has been indicated that the coefficient of friction of the composites decreased with increase in the volume fraction of reinforcements [25,26,50,67,68]. The coefficient of friction of aluminum matrix composite reinforced with CNTs decreases with increasing volume fraction of CNTs in the composite as shown in Fig.…”

“…It has been reported that an increase in the sliding speed causes an increase in the wear rate and decrease in the wear resistance of the MMCs [14,26,96,105], and the variation between the wear rate and sliding speed is usually linear [106,107]. As the sliding speed increases, the interface temperature also increases resulting in (a) the microthermal softening of matrix material [108], (b) oxide formation on the contact area [109], and (c) decrease in flow stress of the material [109].…”

Aluminium Composite with Fly Ash – A Review

“…Anilkumar et al [15] have chosen Al 6061 alloy as the matrix material and fly ash with varying weight percentage (10%, 15%, 20%) with particle size [of 4-25, 45-50, 75-100 μm] as the reinforcement to produce the composite by stir casting. By analyzing the sample, the hardness, tensile strength, compressive strength increases with increase in weight fraction of fly ash.…”

Preparation and mechanical properties of nano-silica/UPR polymer composite

“…Firstly, from the chemical point of view, functional bond owned by high dispersibility nano-silica powder modified by silane coupling agent KH570 connected inorganic nano-silica particles and Brought to you by | University of California Authenticated Download Date | 6/10/15 2:27 AM organic macromolecules of UPR. It resulted in an increase of the intermolecular binding force [8,9]; secondly, from the microscopic interface mechanics point of view, there existed flexible interface layer between two-phase interface which transferred the stress effectively and enabled propagation of the blocked micro-crack [10]; thirdly, from the crystallography point of view, high dispersibility nanosilica powder played the fine grain strengthening role in the UPR matrix because the nano-silica powder resulted in improving the crystal nucleation rate and reducing the UPR matrix crystallinity and grain size [11]. At the base of the above three reasons, the enhancement of the strengthening and toughening performance of nano-silica/UPR polymer composite was apparent.…”