A method for generating cavity model applied for machining a part by electrode discharge machine (EDM) using a tool electrode comprising: a. generating a part-before EDM model defining the geometry of a part to be eroded by the EDM machine to obtain a final part; b. generating an electrode model defining the geometry of the electrode applied for eroding the part; c. computing a cavity model defining the geometrical shape of a cavity, which represent the volume of the material to be eroded by the erode based on the part-before EDM model and the electrode model.

A heterogeneous composite consisting of near-nano ceramic clusters dispersed within a ductile matrix. The composite is formed through the high temperature compaction of a starting powder consisting of a core of ceramic nanoparticles held together with metallic binder. This core is clad with a ductile metal such that when the final powder is consolidated, the ductile metal forms a tough, near-zero contiguity matrix. The material is consolidated using any means that will maintain its heterogeneous structure.

A heterogeneous composite consisting of near-nano ceramic clusters dispersed within a ductile matrix. The composite is formed through the high temperature compaction of a starting powder consisting of a core of ceramic nanoparticles held together with metallic binder. This core is clad with a ductile metal such that when the final powder is consolidated, the ductile metal forms a tough, near-zero contiguity matrix. The material is consolidated using any means that will maintain its heterogeneous structure.

Provided is a zinc-nickel-alloy-electroplated steel sheet comprising a base steel sheet, and a zinc-nickel-plated layer which is located on at least one surface of the base steel sheet and which has a hairline pattern formed thereon, wherein the surface roughness of the surface of the base steel sheet, which forms an interface with the zinc-nickel-plated layer, is 0.7-1.0 um on the basis of the center line average roughness (R.sub.a). According to the present invention, provided are: a zinc-nickel-electroplated steel sheet, which has a beautiful surface appearance after hairline processing, has better price competitiveness than a conventional stainless steel or a vinyl-coated steel, and can ensure high productivity in a coil polishing line; and a manufacturing method therefor.

Provided is a zinc-nickel-alloy-electroplated steel sheet comprising a base steel sheet, and a zinc-nickel-plated layer which is located on at least one surface of the base steel sheet and which has a hairline pattern formed thereon, wherein the surface roughness of the surface of the base steel sheet, which forms an interface with the zinc-nickel-plated layer, is 0.7-1.0 um on the basis of the center line average roughness (R.sub.a). According to the present invention, provided are: a zinc-nickel-electroplated steel sheet, which has a beautiful surface appearance after hairline processing, has better price competitiveness than a conventional stainless steel or a vinyl-coated steel, and can ensure high productivity in a coil polishing line; and a manufacturing method therefor.

A device for machining a work piece creates an electrical potential between an electrode and the work piece or another conducting body proximate to the work piece. The electrical potential establishes an electrical field within the work piece that is expected to repel electrons and create a region of positively charged ions which repel one another. This region is expected to be weakened and material is expected to be removable from this region of the work piece using less force and energy than when machined by traditional machining techniques.

A device for machining a work piece creates an electrical potential between an electrode and the work piece or another conducting body proximate to the work piece. The electrical potential establishes an electrical field within the work piece that is expected to repel electrons and create a region of positively charged ions which repel one another. This region is expected to be weakened and material is expected to be removable from this region of the work piece using less force and energy than when machined by traditional machining techniques.

The present invention provides a bi-metal assembling method. The method provides a machine-shaped aluminum piece and places the machine-shaped aluminum piece into a die-cast mold. The machine-shaped aluminum piece is encapsulated with a magnesium metal liquid and die cast is performed. The assembled bi-metal structure is coated for protection and CNC high-gross treatment and anodizing treatment is performed in the machine-shaped aluminum piece. The magnesium alloy piece is hooked with the machine-shaped aluminum piece for assembling. The bi-metal structure has smooth surface to reduce the time for polishing, surface shrinkage and generation of blowholes. The present invention also provides a bi-metal assembled structure.

The present invention provides a bi-metal assembling method. The method provides a machine-shaped aluminum piece and places the machine-shaped aluminum piece into a die-cast mold. The machine-shaped aluminum piece is encapsulated with a magnesium metal liquid and die cast is performed. The assembled bi-metal structure is coated for protection and CNC high-gross treatment and anodizing treatment is performed in the machine-shaped aluminum piece. The magnesium alloy piece is hooked with the machine-shaped aluminum piece for assembling. The bi-metal structure has smooth surface to reduce the time for polishing, surface shrinkage and generation of blowholes. The present invention also provides a bi-metal assembled structure.

A heterogeneous composite consisting of near-nano ceramic clusters dispersed within a ductile matrix. The composite is formed through the high temperature compaction of a starting powder consisting of a core of ceramic nanoparticles held together with metallic binder. This core is clad with a ductile metal such that when the final powder is consolidated, the ductile metal forms a tough, near-zero contiguity matrix. The material is consolidated using any means that will maintain its heterogeneous structure.