Mechanical characterization of aluminium – red mud metal matrix composites

Abstract

Red mud (bauxite residue) is an industrial waste obtained during the processing of alumina by Bayer’s process. In this work, an attempt has been made to utilize the industrial solid waste as the reinforcement material in aluminium metal matrix composites through powder metallurgy route. Red mud received from NALCO has been subjected to sieve analysis for micron level of 100 µm, 150 µm and 200 µm and milled to nano level of 42 nm using high energy ball mill. Micro and nano structured red mud powders and pure aluminium powder are mixed in a V-Blender, compacted at a pressure of 40 bar and samples are prepared by conventional sintering with vacuum as medium at different weight fractions of 2%, 4%, and 6% red mud. The paper presents mechanical characterization of pure aluminium with red mud such as hardness and compression strength and compression test results are validated with Deform-2D software. An increase in hardness and compression strength is observed with increase in the amount of percentage weight fraction of red mud. Hardness values variation depicts the information that nano red mud specimens have more hardness when compared with micro nature specimens. Hardness and compression strength properties are improved for nano level aluminium-red mud test specimen with 42 nm size and 6% weight fraction of Red mud.