The paper reviews the use of metal powders dispersed in the dielectric fluid and refractory PM electrodes, to initiate workpiece surface modification during EDM. Experimental work details the effects of EDM parameters (up to 270 V) on the hardness / composition of the white layer following die sink machining of AISI H13 tool steel and roll texturing of 2% Cr steel using partially sintered PM electrodes. Similar data are presented following EDM scanning and wire cutting of standard Ti alloy Ti-6Al-4V and a y TiAl. With AISI H13, recast layers were 5-20 mum thick and up to similar to1350 HK0.025. When machining Ti-6Al-4V with WC/Co electrodes, recast microhardness was 600-2900 HK0.025. Wire cutting y TiAl generated porous alloyed layers up to 115 mum thick with extensive cracks and no increase in bulk hardness.
|Number of pages||6|
|Journal||CIRP Annals - Manufacturing Technology|
|Publication status||Published - 1 Jan 2003|