SYNTHESIS AND CHARACTERIZATION OF ALUMINIUM BASED NANOCOMPOSITE REINFORCED WITH BALL MILLED COAL FLY ASH

Abstract

A paradigm shift from monolithic materials to composite materials has been observed in the recent times to achieve the ever changing demands of the manufacturing sector. The composites are being explored in terms of industrial and thermal power plant wastes used as reinforcements. Being a prominent thermal power plant waste, fly ash disposal and utilization is gravitating environmentalists and researchers to propose innovative ideas and feasible implementations. To trace and adjoin an effort to add value to aforementioned cause, an investigation was conducted on fly ash which was milled in tumbler ball mill with predefined input parameters viz. spindle speed as 120 rpm, ball-to-powder ratio as 10:1 (by weight), and milling time was set as 1200 minutes with regular stoppage intervals. Low-energy mill has an extensive application in preparation of new materials, their activation and their process of synthesis for potential merits like cost-effectiveness, reliability, low maintenance and ease of operation over its contemporary high-energy mill. The modifications in chemical and morphological properties of milled fly ash sample were characterized through X-ray diffraction (XRD) technique, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The results inferred that the ball milling process aimed at reducing crystallite domain size of milled fly ash, and also affected the microstructure, functional groups and led to decline in degree of crystallinity (DOC). The milling time was observed as a significant factor to impact extent of these changes. The particles of the raw spherical-shaped fly ash (regularly 5 μm size) were significantly broken down into smaller particles of average crystallite domain size ~30 nm, this change indicated an increase in amorphousness of fly ash that would help in achieving better compatibility and significantly higher reactivity. The fabrication of aluminium based nanocomposite (AMC) reinforced with ball milled coal fly ash was done successfully via stir casting route. It was inferred that ductility of said nanocomposite was lowered on adding the ball milled coal fly ash. In order to maintain the ductility, TiO2 was also added as a reinforcement. The research and analyses defined the achievement of nanostructured fly ash with the low energy mill technique as well as its effective utilization in Aluminium-based composite fabrication and its mechanical characterization.