Synergism between tribological parameters - ``micro-abrasive concentration level{''}, ``micro-abrasive particle type{''}, and ``liquid type{''} of a micro-abrasive slurry composition on the micro-abrasive wear behaviour of Fe-30Al-6Cr (at.\%) iron aluminide alloy

Abstract

Observing the importance of intermetallic materials in mechanical and metallurgical applications, the present work investigates the micro-abrasive wear behaviour in a model-carbide reinforced iron aluminide system. Fe-30Al-6Cr (at.\%) iron aluminide alloy with carbon additions ``as cast{''} specimen was tested. Micrographs revealed a continuous network of eutectic chromium carbides at the interdendritic regions of the D03 ordered aluminide matrix. AISI 52100 bearing steel sphere of diameter 25.4 mm (1 `') was used for wear tests as counter body. Micro-abrasive slurries were prepared with micro-abrasive particles of black silicon carbide - SiC or alumina - Al2O3, with distilled water or glycerin, in four possible combinations of materials double right arrow ``Al2O3 + H2O distilled{''}, ``Al2O3 + glycerin{''}, ``SiC + H2O distilled{''} and ``SiC + glycerin{''}. Further, keeping the normal force constant and together with different levels of micro-abrasive slurries compositions and sliding distances, a factorial experiment was designed. Result analysis showed that wear volume increased with an increase in microabrasive slurry concentration, independently of the type of micro-abrasive particle and liquid. However, the micro-abrasive slurries prepared with SiC and distilled water provided larger wear volumes than the volumes of wear reported under the micro-abrasive slurries formulated with Al2O3 and glycerin. The reason is attributed to the high hardness of SiC particles resulting in high abrasion, whereas the Al2O3 - glycerin slurry lubrication effect restricted high wear. Wear micrographs revealed a change in worn surface morphology from ``grooving micro-abrasion{''} to ``rolling micro-abrasion{''} due to an increase in sliding distance and micro-abrasive slurry concentration.