Method of applying an intermediate material making it possible to ensure the cohesion thereof, method of forming a stack intended for the manufacture of composite components and intermediate material

Abstract

The present invention relates to a method for continuously applying on a deposition surface of an intermediate material composed of a unidirectional layer of reinforcing fibers associated on at least one of its faces to a layer of thermoplastic and/or thermosetting material that does not represent more than 10% of the total weight of the intermediate material.

1 - A method for continuously applying on a deposition surface of an intermediate material composed of a unidirectional layer of reinforcing fibers associated on at least one of its faces to a layer of thermoplastic and/or thermosetting material, the layer(s) of thermoplastic and/or thermosetting material forming the intermediate material not representing more than 10% of the total weight of the intermediate material, wherein said method comprises the steps of:
 providing an intermediate material that has undergone an operation applying spot transverse forces, performed in such a way as to traverse the total thickness of the intermediate material and accompanied by heating, leading to the at least partial melting of the thermoplastic material or the partial or complete polymerization of the thermosetting material, at the spot application of transverse forces, and leading to the penetration of the thermoplastic and/or thermosetting material and creating bonding bridges in the thickness of the unidirectional layer of reinforcing fibers, preferably extending from one main face to the other of the unidirectional layer of reinforcing fibers,   continuously applying said intermediate material along a given movement trajectory, with simultaneous application on the intermediate material of a tension and a pressure, in such a way as to apply the intermediate material on the deposition surface, the deposition being performed by applying one face of the intermediate material in the process of being laid up to a layer of thermoplastic and/or thermosetting material on the deposition surface and/or by applying the intermediate material in the process of being laid up on the deposition surface carrying a thermoplastic and/or thermosetting material, and by activating the thermoplastic and/or thermosetting material that will exist at the interface between the intermediate material and the deposition surface, in such a way as to ensure the bond between the laid-up intermediate material and the deposition surface.   
     
     
         2 - The application method according to  claim 1 , wherein the intermediate material is continuously applied, along a given movement trajectory, under the action of a tension and a pressure in such a way as to apply on the deposition surface a face of the intermediate material in the process of being laid up corresponding to a layer of thermoplastic and/or thermosetting material and to activate, said layer of thermoplastic and/or thermosetting material during its deposition, in such a way as to ensure the bond between the laid-up intermediate material and the deposition surface. 
     
     
         3 - The method for forming a stack by successive applications of intermediate materials composed of a unidirectional layer of reinforcing fibers associated on at least one of its faces to a layer of thermoplastic and/or thermosetting, material, wherein the intermediate materials are continuously applied according to the method of  claim 1 . 
     
     
         4 - The method for forming a stack according to  claim 3 , wherein the stack includes several unidirectional layers of reinforcing fibers, with at least two unidirectional layers of reinforcing fibers extending in different directions. 
     
     
         5 - The method according to  claim 1  wherein, with the exception of the areas bordering the spot application of transverse forces, over at least 50% of its thickness, the layer of unidirectional fibers is not impregnated with thermoplastic and/or thermosetting material. 
     
     
         6 - 9 . (canceled) 
     
     
         10 - The method according to  claim 1  wherein the movement trajectory extends parallel to the direction of the unidirectional fibers. 
     
     
         11 - The method according to  claim 1  wherein the activation is carried out by heating and is followed by cooling. 
     
     
         12 - (canceled) 
     
     
         13 - The method according to  claim 1  wherein the operation of applying spot transverse forces is performed in a direction transverse to the surface of the intermediate material. 
     
     
         14 - (canceled) 
     
     
         15 - The method according to  claim 1  wherein the operation of applying spot transverse forces leaves perforations in the traversed layers. 
     
     
         16 - (canceled) 
     
     
         17 - The method according to  claim 1  wherein the transverse forces are applied at application spots arranged in lines running parallel to one another. 
     
     
         18 - The method according to  claim 1  wherein the intermediate material is composed of a layer of carbon fibers, associated on each of its faces to a layer of thermoplastic and/or thermosetting material. 
     
     
         19 - The method according to  claim 1  wherein the unidirectional layer of reinforcing fibers of the intermediate material is a unidirectional sheet of carbon fibers. 
     
     
         20 - 21 . (canceled) 
     
     
         22 - The method according to  claim 1  wherein the layer(s) of thermoplastic and/or thermosetting material forming the intermediate material is (are) non-woven materials made of thermoplastic fibers. 
     
     
         23 . The method according to  claim 22 , wherein the non-woven materials forming the intermediate Material has (have) a basis weight in the range from 0.2 to 20 g/m 2 . 
     
     
         24 - 25 . (canceled) 
     
     
         26 - An intermediate material composed of a unidirectional layer of reinforcing fibers associated on at least one of its faces to a thermoplastic and/or thermosetting material, the layer(s) of thermoplastic and/or thermosetting material forming the intermediate material not representing more than 10% of the total weight of the intermediate material wherein the intermediate material has undergone an operation of applying spot transverse forces, performed in such a way as to traverse the total thickness of the intermediate material and being accompanied by heating leading to the at least partial melting of the thermoplastic material or a partial or complete polymerization of the thermosetting material, at the application spots of transverse forces, and leading to a penetration of the thermoplastic and/or thermosetting material and creating bridges in the thickness of the unidirectional layer of reinforcing fibers, preferably extending from one main face to the other of the unidirectional layer of reinforcing fibers, and in that the operation of applying spot transverse forces is performed with a density of application points of 40000 to 250000 per m 2  and leads to an opening factor of 0 to 2%. 
     
     
         27 - The intermediate material according to  claim 26 , wherein, with the exception of the areas bordering the application spots of transverse forces, over at least 50% of this thickness, the layer of unidirectional fibers is not impregnated with thermoplastic and/or thermosetting material. 
     
     
         28 - The intermediate material according to  claim 26  the intermediate material is composed of a layer of carbon fibers associated on each of its faces to a layer of thermoplastic and/or thermosetting material. 
     
     
         29 - The intermediate material according  claim 26  wherein the unidirectional layer of reinforcing fibers present in the intermediate material is a unidirectional Sheet of carbon fibers. 
     
     
         30 - 31 . (canceled) 
     
     
         32 - The intermediate material according to  claim 26  wherein the layer(s) of thermoplastic and/or thermosetting material forming the intermediate material is (are) non-woven materials made of thermoplastic fibers. 
     
     
         33 - The intermediate material according to  claim 32 , wherein the non-woven material(s) forming the intermediate material has (have) a basis weight in the range from 0.2 to 20 g/m 2 . 
     
     
         34 - (canceled) 
     
     
         35 - A method for manufacturing a composite part comprising a step of forming a stack using the method of  claim 3  by successive applications of intermediate materials, said intermediate materials each being composed of a layer of reinforcing fibers associated on at least one of its faces to a layer of thermoplastic and/or thermosetting material or of a mixture of thermoplastic and thermosetting materials, followed by a step of diffusion, by infusion or injection, of a thermosetting resin, of a thermoplastic resin or a mixture of such resins, inside the stack, followed by a step of hardening of the desired part by a step of polymerization/reticulation following a defined pressure-temperature cycle, and a cooling step. 
     
     
         36 - 39 . (canceled)