Method of producing microstructured metal sheets

Abstract

In a method of producing microstructured metal sheets, microstructures are made in a metal sheet surface in a continuous embossing step on one side of the metal sheet, while the surface structure of the other side is essentially not changed. The embossing step is carried out by means of an embossing roller which has a negative of the microstructure to be embossed. The flanks of the microstructure form an angle of at least 5° with respect to the perpendicular line, and the negative contains compensating structures in the regions surrounding the microstructure for rendering the forming uniform along the roller slit.

What is claimed:  
     
         1 . Method of producing microstructured metal sheets, comprising: 
 making microstructures in a metal sheet surface in a continuous embossing step on one side of the metal sheet, while a surface on the other side is essentially not changed,    carrying out the embossing step by means of an embossing roller which has a negative of the microstructure to be embossed, wherein flanks of the microstructure form an angle of at least 5° with respect to the perpendicular line, and the negative contains compensating structures in regions surrounding the microstructures for rendering forming uniform along a roller slit.    
     
     
         2 . Method according to  claim 1 , further comprising heating the metal sheet before the embossing step.  
     
     
         3 . Method according to  claim 1 , further comprising carrying out the embossing step in at least of a force-controlled and path-controlled manner.  
     
     
         4 . Method according to  claim 1 , wherein roller pressure of the embossing step is in a range of approximately 30 to 1,000 tons.  
     
     
         5 . Method according to  claim 1 , wherein, after the embossing step, the metal sheet is subjected to a calibrating step.  
     
     
         6 . Method according to  claim 5 , wherein the calibrating step is followed by at least one annealing step for reducing internal tensions of the microstructured metal sheet.  
     
     
         7 . Method according to  claim 6 , wherein the annealing process is carried out with the exclusion of oxygen.  
     
     
         8 . Method according to  claim 5 , wherein, after at least one of the calibrating and annealing steps, the microstructured metal sheet is subjected to a straightening at room temperature.  
     
     
         9 . Method according to  claim 1 , wherein the microstructures preferably have a depth of from approximately 0.1 to 0.5 mm.  
     
     
         10 . Method according to  claim 1 , further comprising thinning the metal sheet by approximately 50%.  
     
     
         11 . Use of the method according to  claim 1 , preferably for the production of a microreactor, a micro heat exchanger, an oil-heated, catalytically or hot-gas heated evaporator, of a membrane module for the separation of H 2  or of a fuel cell.  
     
     
         12 . A method of producing a microstructured metal sheet, comprising: 
 embossing a microstructure and compensating structures surrounding the microstructure on a surface on only one side of a metal sheet, wherein flanks of the microstructure form an angle of at least 5° with respect to the perpendicular line.    
     
     
         13 . The method according to  claim 12 , further comprising heating the metal sheet before embossing.  
     
     
         14 . The method according to  claim 12 , further comprising carrying out the embossing step in at least one of a force-controlled manner and a path-controlled manner.  
     
     
         15 . The method according to  claim 12 , comprising applying a force in the range of approximately 30 to 1,000 tons to the surface of the metal sheet in the embossing step.  
     
     
         16 . The method according to  claim 12 , comprising applying a force in the range of approximately 50 to 500 tons to the surface of the metal sheet in the embossing step.  
     
     
         17 . The method according to  claim 12 , comprising calibrating the metal sheet after the embossing step.  
     
     
         18 . The method according to  claim 17 , comprising cutting the metal sheet in sheets of desired sizes.  
     
     
         19 . The method according to  claim 17 , comprising annealing the microstructured metal sheet to reduce internal tensions after the calibrating step.  
     
     
         20 . The method according to  claim 19 , comprising annealing the microstructured metal sheet with the exclusion of oxygen.  
     
     
         21 . The method according to  claim 19 , comprising straightening the microstructured metal sheet at room temperature after at least one of the calibrating and annealing steps.  
     
     
         22 . The method according to  claim 12 , wherein the microstructures preferably have a depth of from approximately 0.1 to 0.5 mm.  
     
     
         23 . The method according to  claim 12 , further comprising thinning the metal sheet by approximately 50%.  
     
     
         24 . The method according to  claim 12 , wherein the compensating structure has at least one of ribs and grooves having a criss-cross configuration.  
     
     
         25 . The method according to  claim 12 , wherein the compensating structure has a mesa-like configuration.