Method of forming a die

Abstract

A method for forming a die, including forming a pre-formed mold by providing a preliminary layer on a substrate and performing a micro-machining process on the preliminary layer. Due to the micro-machining process, the method can fabricate a pre-formed mold with high precision for forming a mold. The die is fabricated by the mold for performing a molding process to obtain a workpiece with a predetermined shape.

1 . A method of forming a die for performing a molding process to obtain a workpiece with a predetermined shape, the method comprising: 
 providing a substrate;    forming a pre-formed mold by providing a preliminary layer on the substrate and performing a micro-machining process on the preliminary layer;    providing a mold material on the pre-formed mold to form a mold; and    fabricating the die with the mold.    
   
   
       2 . The method as claimed in  claim 1 , wherein the preliminary layer comprises a photo-sensitive material and the micro-machining process comprises a lithographic process, comprising: 
 providing a photo mask above the preliminary layer;    providing a radiation on the photo mask, wherein a portion of the preliminary layer is exposed by the radiation; and    developing the preliminary layer to form the pre-formed mold.    
   
   
       3 . The method as claimed in  claim 2 , wherein the portion of the preliminary layer exposed to the radiation is removed in the developing step.  
   
   
       4 . The method as claimed in  claim 2 , wherein a portion of the preliminary layer unexposed to the radiation is removed in the developing step.  
   
   
       5 . The method as claimed in  claim 1 , wherein the mold material is provided on the pre-formed mold by electroforming.  
   
   
       6 . The method as claimed in  claim 1 , wherein the mold material is provided on the pre-formed mold by powder metallurgy forming.  
   
   
       7 . The method as claimed in  claim 1 , wherein the die is fabricated by assembling the mold with a die base.  
   
   
       8 . The method as claimed in  claim 1 , wherein the die is fabricated by assembling the mold and the substrate with a die base.  
   
   
       9 . The method as claimed in  claim 1 , wherein the molding process is selected from a group consisting of pressing, extruding, die casting, forging, rolling and injection molding.  
   
   
       10 . The method as claimed in  claim 1 , wherein the mold material is selected from a group consisting of nickel cobalt, nickel phosphide, nickel cobalt phosphide, nickel tungsten, nickel rhenium, nickel palladium, nickel chromium, nickel carborundum phosphide, nickel graphite, and nickel manganese. nickel-based alloy and chromium-based alloy.  
   
   
       11 . The method as claimed in  claim 10 , wherein Vickers Hardness Number of the mold is greater than 450HV.  
   
   
       12 . The method as claimed in  claim 10 , wherein precision accuracy of the mold is less than 1 mm.  
   
   
       13 . The method as claimed in  claim 1 , further comprising performing a duration enhancing process on the mold or the die.  
   
   
       14 . The method as claimed in  claim 13 , wherein the duration enhancing process is selected from a group consisting of heat treatment, surface coating, air cooling, and fluid cooling process.  
   
   
       15 . The method as claimed in  claim 14 , wherein the surface coating process comprises coating a protection film on the die with a thickness of 1 to 8 um, the protection film is selected from a group consisting of aluminum nitride, aluminum titanium nitride, chromium nitride, aluminum carbide and diamond-like carbon (DLC).  
   
   
       16 . The method as claimed in  claim 1 , wherein the material of the workpiece is selected from copper, copper alloy, aluminum, aluminum alloy and nonmetal and a combination thereof.  
   
   
       17 . The method as claimed in  claim 1 , wherein the micro-machining process comprises precision electrical discharge machining.  
   
   
       18 . The method as claimed in  claim 17 , wherein a pre-formed mold material for the pre-formed mold is provided in an electrical discharge machining center to perform precision electrical discharge machining.  
   
   
       19 . The method as claimed in  claim 1 , wherein the micro-machining process comprises laser machining.  
   
   
       20 . The method as claimed in  claim 19 , wherein a pre-formed mold material for the pre-formed mold is provided in a laser machining machine to perform laser machining.  
   
   
       21 . The method as claimed in  claim 1 , wherein the micro-machining process comprises rapid prototyping machining.  
   
   
       22 . The method as claimed in  claim 21 , wherein the rapid prototyping machining is selected from a group consisting of stereo lithography (SL), selected laser sintering (SLS), laser engineering net shaping, three dimensional printing (3DP), fused deposition modeling (FDM), laminated object manufacturing (LOM) and inkjet forming method.