Apparatus and method for hybrid machining a workpiece

A method of hybrid machining an electrically-conductive workpiece, comprising the steps of:

• rotating a cutter made of an electrically conductive material with a non-conductive abrasive material dispersed therein;
• electrically powering both an electrically-conductive workpiece and the cutter;
• circulating a coolant between the electrically-conductive workpiece and the cutter;
• positioning the electrically-conductive workpiece relative to the cutter at a predetermined depth of cut;
• and
• moving the cutter relative to the electrically-conductive workpiece in the range between about 3 inches per minute to about 50 inches per minute,
• whereby the material is removed from the electrically-conductive workpiece using a high-speed electro-erosion process that simultaneously uses electrical erosion, mechanical abrasion, and electrochemical dissolution processes.

A method of hybrid machining an electrically-conductive workpiece, comprising the steps of:

• rotating a cutter made of an electrically conductive material with a non-conductive abrasive material dispersed therein;
• electrically powering both an electrically-conductive dovetail blank of a turbine blade and the cutter;
• circulating a coolant between the electrically-conductive dovetail blank and the cutter;
• positioning the electrically-conductive dovetail blank relative to the cutter at a first predetermined depth of cut;
• and
• moving the cutter relative to the electrically-conductive dovetail blank in the range between about 3 inches per minute to about 50 inches per minute to remove material from sidewalls of the electrically-conductive dovetail blank by using a high-speed electro-erosion process that simultaneously uses electrical erosion, mechanical abrasion, and electrochemical dissolution processes.