Wear and corrosion properties of low-cost eggshell-reinforced green AZ91 matrix composites

Abstract

ABSTRACT The present work deals with the production of economical, recyclable and low-weight magnesium matrix composites with waste eggshell (ES). AZ91 magnesium matrix eggshell reinforced composites were fabricated by the powder metallurgy method, and their tribological and corrosion performances were investigated under different test conditions. Results showed that ES enhanced the microhardness value of unreinforced alloy up to 20.4%. Uniform distribution of eggshell particles in the matrix was achieved according to the microstructural investigations. Eggshell reinforcement exhibited a good lubricant effect and developed wear behaviour in almost all test conditions. When 5 wt-% eggshell was added to the alloy, 36.4 wt-% improvement of wear performance was achieved under the load of 20 N at 100 mm s−1 sliding speed. When the reinforcement content was increased, the corrosion rate began to accelerate. The corrosion rate increased almost four times as the reinforcement ratio increased at low pH values. The design of test conditions and the analysis of output responses were studied by the statistical analysis of Taguchi and analysis of variance (ANOVA). ANOVA indicated that the wear rate and corrosion rate were mainly affected by load (52.7%) and pH (21.7%), respectively.