Effect of blending duration on physical, mechanical and tribological behavior of aluminum matrix composites: An experimental analysis

Aluminum matrix composites exhibit a vibrant role in the present research and scientific world due to their astonishing features compared to other conventional materials. Among the various techniques available for processing these composites, powder metallurgy (P/M) is considered one of the prominent techniques. This is because of its identical dispersal of the fillers, near net shape samples, etc. wherein blending is the most imperative step of the process. To accomplish efficient blending of the phases for composite preparation, ball milling is found to be suitable. In this paper, aluminum matrix composites filled with 20 wt% novel reinforcement (extracted from Aegle marmelos) is synthesized via the P/M technique by varying the blending duration from 60 to 240 min to study its effect on the behavior of composites. The mixing of the constituents is carried out at 300 rpm with a ball-to-powder ratio of 10:1 in ball milling. The blended powders were then compacted and sintered in an inert gas atmosphere for consolidation. The hardness, density, and wear tests were conducted to characterize the developed composite specimens. The microstructural characterization was carried out using an optical microscope and SEM, and the elemental composition of the synthesized composite was studied using EDS techniques. The hardness and density were found to have a growing influence up to a ball milling duration of 180 min and beyond this time there is found to be a decrement in the characteristics of the composites. This is due to the damage of the reinforcements observed during lengthier ball milling duration. The wear behavior of the fabricated specimens followed the same trend. Further, grey relational analysis was adopted in this study to determine the degree of relationship between the blending duration and the composites’ behavioral performance.