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A facile fabrication process for bulk PZT microsystems using dry film photoresist and micro powder blasting is presented. Bulk PZT and dry film photoresist etching characteristics are evaluated as a function of process parameters and mask dimensions using 127 μm thick PZT substrates. The resulting process simplifies microscale patterning of bulk PZT compared with existing methods, with selection of suitable etching parameter providing excellent etch rate, selectivity and anisotropy. The technique is used to fabricate two different cantilever microactuator topologies based on piezoelectric d 31 and d 33 mode actuation, demonstrating the capabilities of the patterning method for applications in bulk PZT microelectromechanical systems (MEMS).

Traveling wave ultrasonic micromotors fabricated from a single layer of homogeneous bulk piezoelectric lead zirconate titanate (PZT) are described. The miniature motors are capable of bi-directional rotary motion with controllable speeds. By taking advantage of transverse interdigitated electrodes to excite traveling waves in a patterned bulk PZT substrate, the monolithic micromotor stators are patterned using a simple and low cost fabrication technique based on micropowder blasting. Performance of the ultrasonic micromotors is explored using devices with integrated glass rotors, using defined preload forces applied between the microfabricated stator and rotor elements. For the case of a 4.12 mm diameter PZT stator, a maximum speed of 30 rpm and stall torque of 501 mN · mm are achieved when applying a 323 mN preload force to the rotor.

The wear of a cutting tool determines its life. Lesser the wear, more is the life of cutting tool and consequently the tool has to be replaced less frequently. This results in an increase in productivity of the machining operation, reduces manufacturing lead time and lowers the cost of production. Optimization of the process, use of cutting fluids for lubrication and hard coatings on the tool are the widely used methods to reduce tool wear. It has been recorded in previous studies that application of electric current to moving surfaces in contact, influences the wear of both the surfaces. The wear rate of the anodic surface was reduced and that of cathodic surface was increased. This paper attempts to study the effects of application of DC electric current on wear of turning insert during the turning operation of stainless steel 304 material. In the first phase of study, an L 18 orthogonal array experiment was designed to study the effects of various factors (use of cutting fluid, polarity of cutting tool, applied voltage, cutting speed, feed and depth of cut) on insert wear and surface roughness of stainless steel 304 rod post machining. In the second phase of the experiment, the insert wear at different polarities were recorded at regular intervals of 70 mm cutting length while keeping the cutting parameters constant. Each cut was carried out for a total of 560 mm. The recorded readings are compared.