COMPARISON OF VIBRATIONAL TUMBLING AND ELECTROLYTIC POLISHING ON SURFACE ROUGHNESS PARAMETERS OF ADDITIVELY MANUFACTURED INCONEL 718 ALLOY

This study delves into the comparative analysis of vibrational tumbling and electrolytic polishing, two distinct surface finishing techniques, on the surface roughness parameters of additively manufactured Inconel 718 alloy. Surface roughness significantly impacts the functionality of components, especially in aerospace and automotive applications where Inconel 718 superior mechanical properties are sought after. Vibrational tumbling relies on mechanical abrasion, while electrolytic polishing utilizes chemical processes, offering different pathways to attain smoother surfaces. Three samples were individually subjected to vibrational tumbling, electrolytic polishing and combination of both to determine its effects on surface roughness parameters Sa, Sq, Sp and Sv, evaluated via surface profilometry. Surface wettability was also determined for all the formed surfaces to evaluate the surface nature and functionality. The results indicated that the areal roughness parameter values ranged from Sa = 5.68 to 3.38 µm. The maximum surface height parameter varied from Sz = 53.36 to 32.44 µm, while the maximum valley height Sv ranged from 29.418 to 18.026 µm, and the maximum peak height Sp varied from 23.942 to 14.418 µm across all the printed samples. The findings showed a decrease of 32%, 12% and 42% for vibrational tumbling, electrolytic polishing and combination of both, respectively in the surface roughness values from as built samples. Further, the surface wettability results showed increase in the hydrophilic nature of the surface for each treated surface. The results furnish valuable insights into the efficacy of each method in enhancing surface quality, aiding in informed selection of the optimal surface finishing technique for additively manufactured Inconel 718 components.