Analysis of Abrasive Flow Machining with an Electrochemical Process Aid

Abstract

Electrochemical aided abrasive flow machining (ECAFM) is possible using polymeric electrolytes. The ion conductivity of electrolytes is many times lower than the conductivity of electrolytes employed in ordinary electrochemical machining (ECM). Additions of inorganic fillers to electrolytes in the form of abrasives decrease conductivity even more. These considerations explain why the interelectrode gap through which the polymeric electrolyte is forced should be small. This in turn results in greater flow resistance of polymeric electrolyte, which takes the form of a semi-liquid paste. Rheological properties are also important for performance considerations. Experimental investigations have been carried out for smoothing flat surfaces and process productivity in which polymer electrolytes as gelated polymers and water-gels based on acryloamide were used.

Electrochemical-aided abrasive flow machining (ECA2FM) process: a hybrid machining process

“…A number of electrolytic salt-abrasive laden media can be developed by using a wide variety of salts at different concentrations. Even the strong cyanide-based electrolytic salts can be added for more vigorous electrolytic action under a strictly controlled environment as these are very poisonous [20,21]. The effect of various associated machining parameters on the machining characteristic of material removal (MR) was extensively investigated for ECA 2 FM process.…”

“…It is mentioned that Dabrowski et al also studied the electrochemical aid along with the AFM for the fine finishing of flat surfaces only and achieved more material removal [20,21]. Since the AFM finds its main applicability in the finishing of internal contours, so the developed ECA 2 FM process is to address such finishing requirements.…”

“…The AFM media is suitably modified for the ECA 2 FM process by adding electrolyte salts to it. The developed electrolyte-abrasive laden media has limited ECM action due to lower ion conductivity, less contact time between the electrolyte and electrodes, low ion diffusion ratio and no possibility of selecting between the anion and cation share in the charge transport process [21].…”

“…Based on the parametric optimization of the developed basic AFM setup (using L 9 OA of Taguchi method) [26], pilot experimentation (using one-factor-at-a-time approach) [22,23] for the developed ECA 2 FM process setup and literature review [20,21], five process parameters of voltage (V), salt molal concentration (M), diameter of cathode rod (R), extrusion pressure (P) and abrasives grain size (G) were selected for the experimentation. The three selected levels of the selected process parameters along with values of the fixed process parameters are given in Table 1.…”

“…More material removal was observed in this process due to anodic dissolution at an atomic level along with the abrasion due to mechanical cutting by the abrasives. Dabrowski et al used a number of electrolytic pastes for these experiments and observed more material removal with cyanide-based electrolytic pastes [20,21].…”