Determination on the Effect of Cutter Geometrical Feature for Machining Polyetheretherketone (PEEK) Using Taguchi Methods

This paper details the application of Taguchi method to determine the effect of cutter geometrical features for machining Polyetheretherketones (PEEK) thermoplastic. The planned experiment was conducted by using Taguchi’s orthogonal array taking into account the ball nose geometrical parameters such as helix angle, rake angle, clearance angle and number of flute. The measured response is the machined surface roughness, which is important for the component functionality. In addition, ANOVA was used to validate the percentage contribution of each factor. The obtained results reveals that, less number of flutes is the main factor contributed towards fine surface roughness for this thermoplastic. Fewer flutes provide a smooth flow of chip ejection and minimize the friction on the cutting zone which is vital for polymeric material such as PEEK. High helix and rake angles also influence the machined surface roughness as both angles provide optimum shearing force to produced better surface finishing. However, it is found that clearance angle is less significant on roughness since the function of clearance angle is to control the process damping and stability. The main conclusion of this study is that there is significant effect on the cutter geometrical feature on machining performance and thus conclude the need of special design cutter for effectively machining PEEK plastic.