1st International Conference of Advanced Materials and Manufacturing Technologies, Karabük, Turkey, 25 - 27 October 2017, vol.1, no.1, pp.21-26
Drilling operation is required for assembly of carbon fiber reinforced polymer (CFRP) composites. Surface roughness, hole entry delamination and hole exit uncut fibers occurred during drilling are important factors affecting the properties of the drilled holes. In this study, the drilling parameters for the minimum surface roughness (Ra), delamination factor (Df) and uncut fibers factor (UCFF) were optimized for drilling of CFRP composites with uncoated and TiN coated solid carbide drills. Machinability experiments were carried out in Taguchi Method L18 orthogonal array experimentation. Firstly, the % effects of cutting tool type (uncoated, TiN coated) and drilling parameters (cutting speed, feed rate) on Ra, Df and UCFF were determined via Variance Analysis. In the second stage, the drilling parameters for minimum Ra, Df and UCFF are optimized using Gray Relational Analysis (GRA). TiN coated tools provided lower Df and UCFF values while better Ra was achieved with uncoated tools. No significant effect of cutting tool type on Ra, Df and UCFF was observed. The most effective parameter on Ra was the cutting speed, whereas the most effective parameter on Df and UCFF was feed rate. As a result of the GRA, minimum Ra, Df and UCFF values were achieved with TiN coated drills at V:45 m/min cutting speed and f:0.04 mm/rev feed rate.