CAE-ECM system for electrochemical technology of parts and tools

298 J. Kozak et al. / Journal of Materials Processing Technology 107 (2000) 293±299Fig. 8. Experimental veri®cation of ECM with ¯at electrode. sinking feed rate V f ˆ 1mm=min; inlet electrolyte velocity w ˆ 10 m=s; outlet pressure p k ˆ 0:1 MPa; accuracy of calculated tool-electrode shape DF ˆ 2 mm.Calculated distributions of S, w, p, T, b and i as functionsof distance along the electrolyte ¯ow (with x ˆ 0 at the inlet)are shown in Fig. 10. The change in interelectrode gapwidth, S, results from blade's feather pro®le change aswell as from change of physical conditions along electrolyte¯ow.To evaluate in¯uence of ECM input parameters on interelectrodegap distribution (or, in other words, on workpieceshape error distribution) computer simulations for differentvalues of voltage, feed rate and inlet electrolyte velocitywere performed. Following values for these parameters wereused: inlet electrolyte velocity w ˆ 5, 10 and 15 m/s; voltage U ˆ 8, 12, 16 V; feed rate V f ˆ 0:75, 1.00, 1.50 mm/min.Fig. 9. Tool and blade pro®le.Some results for these simulations are shown in Fig. 11.The biggest values of gap width, S(x), occur at the pointwhere electrolyte exits that gap. They result from electrolytea conductivity change that is caused by temperature and gasfraction increase. Decrease of inlet velocity of electrolytecauses decrease of gap width at the electrolyte outlet.Gap width signi®cantly depends on pressure at the outletthat can be seen from graphs in Fig. 11 for p k ˆ 0:10 and0.15 MPa.Fig. 10. Calculated distributions of S, w, p, T, b and j as functions ofdistance along the electrolyte ¯ow.Fig. 11. Gap width for different input parameters.