Geometric approaches to enhancing edge quality in planar milling

Abstract

Experimental studies show that the in-plane exit angle is a crucial factor affecting edge quality in milling operations. Serious edge defects start to form at tool exits with an exit angle larger than a threshold value determined by the depth of cut, feed rate and material ductility, regardless of other cutting parameters. By adjusting the tool path, the exit angle can be used as a handle for changing the defect formation on the machined edges. A computational framework that minimizes the primary edge defect in planar milling by appropriate selection of the orientation for parallel tool paths is presented. Algorithms are developed to predict defect locations on linear and circular edges while the tool is moving along a given tool path. Process-planning software implemented with these algorithms demonstrates the feasibility of enhancing edge quality with geometric approaches in an automatic manner. The paper provides an effective solution to the edge defect problem in circumstances such as micro-milling and precision manufacturing where edge finishing is difficult to perform.

Tool Path Planning for Edge Quality Enhancement in Planar Milling of Free Form Contours

“…The algorithms [7,8] proposed for avoiding tool exits in planar milling of 2D polygons are not applicable to free-form contours. There exist no explicit solutions for predicting tool exits, as the part vertices or edges cannot be unambiguously defined.…”

“…Narayanaswami and Dornfeld [6] estimated the total length of primary exit burr locations in the planar milling of 2D polygons. The total burr length is used as a criterion for selecting tool path orientation to minimize exit burrs [7]. An approach was developed for avoiding tool exits by adjusting tool positions around the vertices of 2D polygons [8].…”

Improvement of workpiece quality in face milling of aluminum alloys

“…Non-compliance with one of the quality requirements mentioned above can lead to malfunction of a component in operation. In addition to its importance for functionality of part, an unsatisfactory edge shape complicates the manageability of the workpiece and can lead to injuries while handling the workpieces (Chu and Chen, 2005). To ensure the edge shape as required, deburring processes are often necessary.…”