Fine abrasive water jet machining of piezoelectric ceramics: cutting parameters optimization

Piezoelectric ceramics are increasingly applied in optical, electronic, mechanical and biomedical applications thanks to their inherent physical properties such as electrical behavior, electromagnetic response, high temperature strength, hardness and corrosion resistance. Nevertheless, this kind of materials is usually very difficult-to-machine by conventional technologies, while its applications become more and more demanding in terms of quality and precision. In such a scenario, the Fine Abrasive Water Jet (jet diameter less than 0.5 mm) represents a very appealing and promising technology compared to micro-milling, laser or EDM, offering many advantages such as the absence of thermal distortions, high flexibility and versatility, small cutting forces and the increasing capability to cut smaller and smaller features. In the present work, carried out at Tecnalia R&I in collaboration with Politecnico di Milano, piezoelectric material lead titanate zirconate (PZT) thin sheets machining is investigated with a DOE approach, in order to optimize the FAWJ cutting parameters and to test its capability as a concrete high-precision technology to machine ceramic materials. Finally, an application of PZT as base material for micro positioning actuators is presented as a case study.