| 205 / | HD | ELECTROLYSIS: PROCESSES, COMPOSITIONS USED THEREIN, AND METHODS OF PREPARING THE COMPOSITIONS |
| 640 | DF | ELECTROLYTIC EROSION OF A WORKPIECE FOR SHAPE OR SURFACE CHANGE (E.G., ETCHING, POLISHING, ETC.) (PROCESS AND ELECTROLYTE COMPOSITION) {19} |
| 660 | DF | .~ Preliminary cleaning or shaping of workpiece {1} |
| 661 | ![]() | .~.~ Nonelectrolytic (e.g., mechanical grinding, milling, machining, etc.) |