Method and device for producing a reinforced component by thixoforming

Abstract

A method is disclosed for producing a reinforced component from a composite material (MMC). A metallic matrix material is reinforced by embedded fibers or particles, for which purpose a semi-finished product is prepared that comprises fibers and particles or both, together with a metallic matrix material. Forming is effected by thixoforming in a mold at a temperature above the solidus temperature and below the liquidus temperature of the metallic matrix material. The method allows to manufacture near-net-shaped products with excellent mechanical properties.

1 . A method for producing a component from a composite material (MMC), comprising the steps of: 
 providing a fibrous structure;    consolidating said fibrous structure with a metallic matrix material to a semi-finished product;    transferring said semi-finished product into a mold;    heating said semi-finished product to a temperature above a solidus temperature and below a liquidus temperature of the metallic matrix material;    thixoforming said semi-finished product to form a product; and    cooling said product down to room temperature.    
   
   
       2 . The method of  claim 1 , wherein said semi-finished product is produced by a process selected from the group formed by: 
 laminating layers of fibrous structures and metal sheets to form a prepreg;    coating a fibrous structure with a metallic matrix material;    laminating a plurality of coated fibrous structures to form a prepreg;    coating a fibrous structure with the metallic matrix material by a screen printing process;    coating a fibrous structure with the metallic matrix material by electrostatic charging;    coating a fibrous structure with the metallic matrix material by electrophoretic deposition from an aqueous suspension, at the aid of an electric field; and    coating a fibrous structure with the metallic matrix material by thermal spraying.    
   
   
       3 . The method of  claim 2 , wherein said fibrous structure is coated by a thermal spraying process selected from the group formed by: 
 atmospheric plasma spraying, wire flame spraying and electric arc spraying.    
   
   
       4 . The method of  claim 1 , wherein a proportion by volume between said metallic matrix material and a reminder of said semi-finished product is selected to be in the range of 0.8 to 3.0.  
   
   
       5 . The method of  claim 2 , wherein the fibrous structure during thermal spraying is maintained under a tensile stress.  
   
   
       6 . A method for producing a component from a composite material (MMC), comprising the steps of: 
 mixing a metallic matrix material with a reinforcement material by a method selected from the group formed by granulating and pelletizing;    transferring a mixture obtained from said mixing step into a mold;    pressing said mixture within said mold to form a semi-finished product;    transferring said semi-finished product into a die;    heating said semi-finished product to a temperature above a solidus temperature and below a liquidus temperature of the metallic matrix material;    thixoforming said semi-finished product within said die to form a product; and    cooling said product down to room temperature.    
   
   
       7 . The method of  claim 6 , wherein said reinforcement material is formed by chopped fibers.  
   
   
       8 . The method of  claim 7 , wherein said chopped fibers have a length of between 0.5 and 20 mm.  
   
   
       9 . The method of  claim 6 , wherein a proportion by volume between said metallic matrix material and a reminder of said semi-finished product is selected to be in the range of 0.8 to 3.0.  
   
   
       10 . The method of  claim 6 , wherein said reinforcement material is selected from the group formed by: 
 pulverized particles, oxide ceramics and carbides.    
   
   
       11 . The method of  claim 1 , wherein said fibrous structure is prepared with at least one layer made from long fibers, said long fibers being defined by a characteristic selected from the group formed by: 
 a length of at least one millimeter; and    an aspect ratio (length-to-diameter ratio) of at least 50.    
   
   
       12 . The method of  claim 11 , wherein a succession of layers is laminated to form a prepreg, wherein said succession of layers comprises at least two layers selected from the group formed by: 
 a fibrous structure comprising long fibers;    a fibrous structure coated with a metallic matrix material;    a metallic matrix material layer;    a mixture of metallic matrix material and chopped fibers;    a mixture of metallic matrix material and reinforcement particles.    
   
   
       13 . The method of  claim 6 , further comprising the step of providing at least one graded layer within said first mold.  
   
   
       14 . The method of  claim 1 , wherein said metallic matrix material is selected from the group formed by: 
 an aluminum alloy;    a copper alloy;    an alloy comprising aluminum, magnesium and silicon as main components;    an alloy comprising copper and tin as main components;    an alloy comprising zinc as main component.    
   
   
       15 . The method of  claim 1 , wherein said metallic matrix material is selected from the group formed by: 
 an alloy of the type AlMg4.5Mn0.4;    an alloy of the type AlMgSil,    an alloy of the type AlSi7Mg,    an alloy of the type AlSi3,    an alloy of the type AlSi12,    an alloy of the type CuZn40A12 and    an alloy of the type CuSn13.5A10.3.    
   
   
       16 . The method of  claim 1 , wherein said metallic matrix material comprises embedded particles, said embedded particles being selected from the group formed by oxide ceramics, carbides, nitrides, metals, alloys and tribologically active materials.  
   
   
       17 . The method of  claim 1 , wherein said fibrous structure comprises fibers selected from the group formed by: 
 carbon;    silicon carbide;    aluminum oxide;    mullite;    a modification of a carbon fiber with at least one component selected from the group formed by nitrogen, titanium, boron, carbon and silicon;    a modification of a silicon carbide fiber with at least one component selected from the group formed by nitrogen, titanium, boron;    a modification of an aluminum oxide fiber with at least one component selected from the group formed by nitrogen, titanium, boron, carbon and silicon;    a modification of a mullite fiber with at least one component selected from the group formed by nitrogen, titanium, boron, carbon and silicon.    
   
   
       18 . The method of  claim 1 , wherein said fibrous structure comprises fibers selected from the group formed by: 
 a fiber coated on its surface;    a fiber provided with a diffusion barrier;    a fiber provided with a protective layer;    a fiber provided with a primer layer.    
   
   
       19 . The method of  claim 1 , wherein said fibrous structure comprises fibers having a diameter of between 5 and 20 μm.  
   
   
       20 . A method for producing a component from a composite material, comprising the steps of: 
 preparing a mixture from a metallic matrix material and a reinforcement material;    providing a fibrous structure;    applying said mixture by a coating process onto said fibrous structure and forming a semi-finished product there from;    transferring said semi-finished product into a die;    heating said semi-finished product to a temperature above a solidus temperature and below a liquidus temperature of the metallic matrix material;    thixoforming said semi-finished product to form a product; and    cooling said product down to room temperature.