Pulsed Electrochemical Machining (pECM) uses the principles of ECM but pulsed
voltage/current providing; lower current improving energy usage, lower material removal rate
& better surface finish, vastly improved dimensional accuracy machining hard/high strength,
temperature resistant materials, smaller machining gaps between cathode & workpiece to
produce finer detail, follows geometry of the cathode reducing cathode
reshaping/regeneration, has less metal Hydroxide waste (hard to dispose of). The problem
facing the conventional ECM market is components must have 2-3mm additional material
prior to machining to enable removal of defects/achieve final geometry, wasting expensive
materials. Components can be nearer net shape if manufactured using pECM.
Typically compressor/turbine blades are forged to oversized dimensions, machined by
conventional methods (milling/turning) or, one side at a time using single cathode (axis) ECM
leaving a “pip” which needs removing via tumbling /hand grinding/polishing with no control
over accuracy of final geometry/dimensions. A twin cathode (axis) ECM would machine both
sides of the blade simultaneously, leaving no pip. There is no known production of twin axis
ECM machine tools in the world nor any twin axis pECM. A twin axis pECM would be the
ideal machining method to complete manufacture of compressor/turbine blades to final
tolerances/geometries & surface finish. If twin axis pECM could be developed, it would have
a huge impact on the global aerospace/turbine market.
The proposed study involves exploration of the ECM market in aerospace (civil & military)
for the manufacture of compressor/turbine blades & to see if development of a modularised
platform technology of pECM machines, capable of duel sided machining (twin axis/multi
axis) can be adapted to meet industrial applications at a competitive price & be viable,
research & investigate the use of metal dipped plastic as cathodes to provide cheaper
tooling/manufacturing costs