Experimental investigation on ultrasonic vibrational drilling of carbon fiber reinforced polymer laminates

• Main Author: Chui, Yan Li.
• Other Authors: Sathyan Subbiah
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/20695
• Institution: Nanyang Technological University

This report explores the novel concept of ultrasonic vibrational drilling of uni-directional carbon fiber reinforced polymer (CFRP) composite laminates. Three customized drill bits namely Dagger, Reamer and Router are used to perform the hole drilling experiments with two different feed rates and two rotational drill speeds. The particular objective of the present work was to conduct drilling experiments of CFRP laminates to investigate the effects of ultrasonic vibrational drilling. CFRP laminates are made of carbon-fiber reinforced/epoxy-resin matrix composite plies. In view of the anisotropy due to carbon-fiber orientation, challenges in drilling of CFRP laminates arise. Experiments were performed to characterize major hole quality parameters and cutting characteristics encountered when drilling CFRP laminates. In an attempt to improve hole quality, the specific drilling assisted by ultrasonic vibration of 40 kHz was examined. Experimental work was performed to measure thrust forces encountered and characterize major hole quality parameter. All results were analyzed and compared between conventional drilling and ultrasonic vibrational drilling. The results indicate that the thrust force is reduced during vibrational drilling. In addition, better hole quality is obtained when compared to conventional drilling. Results are also studied closely to come out with possible ideal combinations of cutting conditions that will aid in cost saving and ease of manufacturing.