High-performance machining of fiber-reinforced materials with hybrid ultrasonic-assisted cutting

A main approach for sustainable and efficient products is the application of innovative materials like fiber-reinforced plastics. Despite the excellent properties, the machining requirements, especially the hard cutting conditions, restrain the wide application of these materials. Thus a major task is the realization of the required part qualities combined with efficient machining strategies. The project ULTRASPAN, a joint venture of partners from industry and research institutes funded by the BMBF, attends to this challenge. The goal is the development of new hybrid machining concepts and process technologies for enhanced cutting of composite materials with ultrasonic-assistance. Prior condition is the development of novel robust actuators. Therefore, prototypic actuators for longitudinal and torsional vibration systems are developed in the project. Besides the novel actuator concepts, the results of ultrasonic-assisted drilling (UAD) on composite parts are presented in this paper. Machining tests in drilling of fiber-reinforced plastics with the novel prototype actuator systems were performed. Focus of the investigation was the influence of the ultrasonic vibration support on the bore quality. The superimposition of drilling with ultrasonic vibrations influences the process characteristics and engagement of the cutting edge. Machining tests showed the potential to enhance the bore quality with UAD in a certain parameter field.