Modulation assisted drilling of inconel-718 ni-based superalloy

Abstract

Modulation assisted drilling (MAD) of a Ni-based superalloy; Inconel-718 has been reported in this paper. Drilling is one of the most critical machining processes during the manufacturing of various products. During MAD, a controlled low-frequency vibration was superimposed in the feed direction, and its effect on tool flank wear was investigated. For comparison, conventional machining was also done under similar machining parameters. A tribo-MAM tool holder (Patented tool-M4 Sciences) was retrofitted on a computer controlled lathe for providing the vibration frequency to the drill bit. Flank wear was directly measured by the tool condition monitoring method. The maximum flank wear was measured with a tool maker’s microscope. The used carbide drills were inspected under the scanning electron microscope (SEM) to establish the probable wear mechanism. The results of the study showed that the tool flank wear (VBmax) got reduced significantly during MAD in comparison with that during the conventional drilling (CD). Among the investigated modulation conditions, a modulation frequency of 183 Hz with an amplitude of 0.0018 mm resulted in the least tool wear. However, at a higher feed rate in CD, a catastrophic failure of drill occurred due to cutting-edge fracture.