ELECTRICAL-DISCHARGE TEXTURING

The paper outlines a low cost electrical discharge machining arrangement for the texturing of steel rolls used in the cold rolling of sheet steel and aluminium. The particular electrical discharge texturing (EDT) technique used affords a high degree of process control compared with more conventional methods and, therefore, optimisation of roll texture is possible through the selection of the appropriate operating variables. Sample EDT operating data are presented covering the effects of peak current and on-time relative to roll surface roughness (Ra) and peak count (Pc). Scanning electron micrographs are included of textured roll and sheet steel surfaces together with three dimensional topographical representations and a simulation of the effects of roll wear and topography transfer. Roll surface integrity data are also given which detail the structure and hardness of the white layer produced as a consequence of the EDT process.