Electrical discharge machining of complex holes using shape memory alloy electrodes

A method of electrical discharge machining at least one shaped hole in a metallic article using a shape memory alloy electrode comprising the steps of:

• processing at least one NiTi shape memory alloy wire electrode to retain a trained shape, said processing step comprising the steps of:
• i)forming the electrode to a desired end shape by coiling the electrode around a fixture to capture the shape of the fixture, ii)restraining the electrode to the desired end shape by heat treating the electrode at about 1000.degree. F. for about 10 minutes, followed by water quenching the electrode;
• loading the electrode in an electrical discharge machining device;
• and
• electrical discharge machining at least one shaped hole in the article, whereby the hole approximates the trained shape of the electrode.

A method of electrical discharge machining at least one groove in a metallic article using a shape memory alloy electrode comprising the steps of:

• processing at least one shape memory alloy wire electrode to retain a trained shape, said processing step comprising the steps of:
• i)forming the electrode to a desired end shape by coiling the electrode around a fixture to capture the shape of the fixture, ii)restraining the electrode to the desired end shape by heat treating the electrode, followed by water quenching the electrode;
• loading the electrode in an electrical discharge machining device;
• and electrical discharge machining at least one groove in the article.