Experimental investigations into the nano-finishing of Al2024 tubes using the rotational-magnetorheological abrasive flow finishing (R-MRAFF) process

Aluminum alloy 2024 (Al2024) tubes have extensive applications in the aerospace industry; however, finishing their interior surfaces is a big challenge. In this case, many traditional and advanced machining processes are inefficient due to the limitations of machining tools. To overcome these challenges and limitations, rotational-magnetorheological abrasive flow finishing (R-MRAFF) process has been proposed. In this process, magnetorheological polishing (MRP) fluid, experiences a rotational motion in addition to the reciprocating motion on the workpiece surface asperities. In the present work, the effect of the R-MRAFF processing time on the internal finishing of Al2024 tubes has been investigated experimentally in terms of two essential parameters; surface roughness and material removal. In this regard, an industrial prototype of the R-MRAFF process has been developed. Experimental results express the efficiency of the R-MRAFF process for nano-finishing of Al2024 tubes. The surface roughness and material removal values at a processing time of 15 min are 26.3 nm and 41 mg, respectively. In addition to the morphological observations, the surface topography results emphasize the removal of peaks by the R-MRAFF process, besides creating deep scratches with negative skewness on the surface texture of Al2024 tubes, which results in increased oil holding capacity.