Development and properties evaluation of marble dust reinforced ZA-27 alloy composites for ball bearing application

Abstract

In this work, the usability of waste marble dust as a reinforcement in the development of ZA-27 alloy composites has been investigated for use in ball bearing application. ZA-27 alloy composites with five different concentration of marble dust viz. 0, 2.5, 5, 7.5, and 10 wt% of marble dust were fabricated using high-temperature vacuum casting. Developed composites were evaluated for various mechanical properties such as compressive strength, impact strength, flexural strength, and stress intensity factor (SIF) for 4 different crack lengths viz. 1, 2, 3, and 4 mm. Compressive strength and impact strength showed improvement for marble dust concentration up to 7.5 wt% while flexural strength and SIF kept on increasing continuously with increase in reinforcement content up to 10 wt% marble dust. There was ∼31%, ∼100%, ∼49%, and ∼184% improvement in compressive strength, impact strength, flexural strength, and SIF (for 4 mm crack length), respectively in comparison to those of 0 wt% marble dust composite. Fracture surface morphologies generated during fracture toughness analysis were examined using scanning electron microscopy to investigate the nature of failure. In addition to mechanical properties, thermo-mechanical behavior of the fabricated composites was evaluated by dynamic mechanical analysis (DMA) in the temperature range 25 °C–250 °C. DMA results revealed a continuous increase in storage modulus, loss modulus and tan delta with increase in marble dust concentration, except the loss modulus for 7.5 wt% marble dust. Based on the proposed composites, finite element method (FEM) analysis was carried out for single-row deep groove ball bearing application to investigate hardness, contact stress, and displacement between inner and outer race at specific loading condition (500 N) and then, validated by mathematical modeling.