An In-Process Intervention to Mitigate the Effect of Built-Up Edges in Micromilling

Abstract

This paper is focused on developing an in-process intervention technique that mitigates the effect of built-up edges (BUEs) during micromilling of aluminum. The technique relies on the intermittent removal of the BUEs formed during the machining process. This is achieved using a three-stage intervention that consists first of the mechanical removal of mesoscale BUEs, followed by an abrasive slurry treatment to remove the microscale BUEs. Finally, the tool is cleaned using a nonwoven fibrous mat to remove the slurry debris. An on-machine implementation of this intervention technique is demonstrated, followed by a study of its influence on key micromachining outcomes such as tool wear, cutting forces, part geometry, and burr formation. In general, all relevant machining measures are found to improve significantly with the intervention. The key attributes of this intervention that makes it viable for micromachining processes include the following: (i) an experimental setup that can be implemented within the working volume of the microscale machine tool; (ii) no removal of the tool from the spindle, which ensures that the intervention does not change critical process parameters such as tool runout and offset values; and (iii) implementation in the form of canned G-code subroutines dispersed within the regular micromachining operation.