A wire electric discharge machining apparatus includes upper and lower wire guide units including wire guides configured to position and guide a wire electrode and a jet nozzle configured to supply a jet flow coaxially with the wire electrode, and a core holding pad having a through-hole passing therethrough in an upward/downward direction, and in which a plurality of protrusion sections having an equal distance from upper surfaces thereof to a lower surface of the workpiece are formed. The core holding pad is disposed on the lower wire guide unit such that the core holding pad approaches the lower surface of the workpiece as closely as possible.

A wire electric discharge machining apparatus includes upper and lower wire guide units including wire guides configured to position and guide a wire electrode and a jet nozzle configured to supply a jet flow coaxially with the wire electrode, and a core holding pad having a through-hole passing therethrough in an upward/downward direction, and in which a plurality of protrusion sections having an equal distance from upper surfaces thereof to a lower surface of the workpiece are formed. The core holding pad is disposed on the lower wire guide unit such that the core holding pad approaches the lower surface of the workpiece as closely as possible.

The present method for machining a part includes wire electro-discharge machining the part to create a recast layer, and then removing a zinc content of the recast layer without substantially altering the remainder of the initial composition make-up of the recast layer. The final composition make-up of the recast layer is substantially identical to the initial composition make-up except for the removed zinc content.

The present method for machining a part includes wire electro-discharge machining the part to create a recast layer, and then removing a zinc content of the recast layer without substantially altering the remainder of the initial composition make-up of the recast layer. The final composition make-up of the recast layer is substantially identical to the initial composition make-up except for the removed zinc content.

An additive manufactured workpiece includes one or more cavities having an inner surface. A dielectric interface is formed in the cavity, and conforms to the inner surface. The additive manufactured workpiece further includes an in-situ electrode in the cavities. The dielectric interface is interposed between the in-situ electrode and the inner surface of the workpiece.

An additive manufactured workpiece includes one or more cavities having an inner surface. A dielectric interface is formed in the cavity, and conforms to the inner surface. The additive manufactured workpiece further includes an in-situ electrode in the cavities. The dielectric interface is interposed between the in-situ electrode and the inner surface of the workpiece.

A method for machining a part includes wire electro-discharge machining the part, and then selectively reducing a zinc content of the residual recast layer left on a surface of the part, while otherwise leaving the recast layer substantially intact.

A method for machining a part includes wire electro-discharge machining the part, and then selectively reducing a zinc content of the residual recast layer left on a surface of the part, while otherwise leaving the recast layer substantially intact.