Tribological behaviour of eggshell ash and boron carbide reinforced ZA-27 hybrid metal matrix composites under dry sliding conditions

Abstract

The present investigation intends to study the tribological behaviour of ZA-27 alloy reinforced with low-cost eggshell ash (ESA) and boron carbide (B 4 C) particles by utilizing a stir casting process to fabricate hybrid metal matrix composites. The percentage of ESA and B 4 C particles are added in the range of 0-5 wt.%. Composites being tested for density, porosity and microhardness. A pin-on-disc DUCOM tribometer used to investigate the friction and wear behaviour of composites with a varying load of 10 to 50 N at a constant sliding speed of 1 m s −1 and a fixed sliding distance of 1500 meter. To study the influence of speed on friction and wear behaviour, tribological testing was also performed at a sliding speed of 2 m s −1 and 3 m s −1 . The composites microstructure revealed the presence of ESA and B 4 C particles examined by scanning electron microscope (SEM) and energy-dispersive x-ray spectroscopy (EDS) analysis confirmed the elemental composition of reinforcement particles present in the matrix. Composites density decreased when reinforced with ESA and B 4 C particles and the maximum decrease in density was about 3.12%. Porosity of the composites increased with the increase in wt.% of B 4 C particles. Addition of ESA and B 4 C particles significantly improved composites microhardness. The coefficient of friction (COF) and wear loss showed an increasing trend with the increase in load, whereas COF decreased and wear loss increased on higher sliding speeds. Composites showed superior wear resistance over base alloy under all test conditions. Worn surface morphology indicated the delamination, plastic deformation and ploughing at low speed, whereas abrasion was the dominant wear mechanism at higher sliding speeds. Therefore, this hybrid composite may have the potential to be used as a bearing material for tribological applications over monolithic ZA-27 alloy.

Dry Sliding Wear Behaviour of Al6061 Hybrid Metal Matrix Composites using Response Surface Methodology

“…B4C with an average particle size of 75 µm along with eggshell ash having a similar average particle size was used to fabricate hybrid composites. The details procedure for the preparation of eggshell ash is reported elsewhere [13].…”

Tribological behaviour of ZA/ZrB2 in situ composites using response surface methodology and artificial neural network

“…The tribological properties of this material system are affected by various other parameters such as surface morphology, loading condition, working medium, operating velocity, sliding distance, and so on. In automobile parts, where tribological properties are key, excessive applied load, velocity and sliding distance led to high wear and resulted in failures of components [4,5]. It's become essential to predict the wear parameters to stop catastrophic and economic losses.…”