Modeling of the electrochemical machining process

Technical Report · Sat Jan 01 00:00:00 EST 1977

OSTI ID:7223318

Riggs, J B

A computer-implemented model for predicting electrochemical machining (ECM) work piece geometry was developed and then verified by electrochemically sinking holes in copper and 302-stainless steel using a commercial ECM machine. A tool piece of cylindrical symmetry was chosen because it provided a two-dimensional problem and also because of its mechanical simplicity. The model was developed to predict the dependence of ECM work piece geometry on the operating conditions of the process (i.e., electrolyte conductivity, applied voltage, and tool piece feed rate) and on the physical and electrochemical characteristics of the electrodes (e.g., anodic current efficiency, reversible cell potential, and charge transfer overpotential). The operating conditions for the electrochemical machining of copper were adjusted to avoid any part of the anode being in the transpassive region because of the lack of quantitative data describing the anodic films formed during transpassive dissolution. Because neither the reversible cell potential nor the charge transfer overpotential of the electrodes was known for the systems under consideration, an estimate of their combined effect was deduced from several experimental profiles. This empirically determined estimate of the potential drop excluding IR drop was found to be in reasonable agreement with the theoretical predictions. The empirically determined estimate was used by the model in the prediction of eight equilibrium ECM cuts and of six unsteady-state profiles for copper and gave satisfactory correspondence with experiment. A similar approach was used for model predictions for 302-stainless steel. A method of correlating characteristics of equilibrium ECM cuts with the operating variables was also presented. This method can be used to predict the operating conditions which yield the desired cut dimensions.

• Research Organization: California Univ., Berkeley (USA). Lawrence Berkeley Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7223318
• Report Number(s): LBL-6019
• Resource Relation: Other Information: Thesis
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COPPER
ELECTROCHEMICAL MACHINING
STAINLESS STEEL-302
AUTOMATION
COMPUTERS
FORECASTING
FUNCTIONAL MODELS
ALLOYS
CHEMICAL MACHINING
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-NICKEL STEELS
CORROSION RESISTANT ALLOYS
ELEMENTS
IRON ALLOYS
IRON BASE ALLOYS
MACHINING
METALS
NICKEL ALLOYS
STAINLESS STEELS
STEELS
TRANSITION ELEMENTS
360101* - Metals & Alloys- Preparation & Fabrication