ULTRASONIC MACHINING

                     ULTRASONIC  MACHINING

This is also an impact erosion process to machine material is removed by repetitive impact of abrasive particles carried in a liquid medium in the form of slurry under the action of a shaped vibrating tool attached to a vibrating mechanical system

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The principal is schematically, where a shaped to is given a mechanical vibration.The vibration causes the abrasive practical in the slurry to initiate the fracture in work material observed as stock removal of the latter.the abrasive outside the domain of the tool remain inactive and so the removal process is an impact from machining process the machined surface is approximately the inverse profile the tool form.

Ultrasonic machining of hard material is classified into two groups:-

1.working with freely directed abrasive using frequency(grinding).

2.Precision ultrasonic machining under the preview of present deterioration.

                               

safer zone of ultrasonic machining is between 19khz to 25khz .so the tool is to be vibrated with an amplitude of vibration of 75 microns at a frequency between 19khz to 25khz.
                                  Abrasive in a slurry form is more effective compared to abrasive in loose form since the liquid would help removal of material due to cavitation effect during the return stroke of the tool. Moreover, the liquid will help evenly distribution abrasive particles into the working gap.

The vibrator is made to obtain sufficient amplitude the length of propagation is made half-wavelength.the concentrator become a volume resonator tuned to the same frequency which produces the best condition for maximum power transfer