Manufacturing process for a plated product comprising a support part in steel and an anticorrosion metallic coating

Abstract

The aim of the present invention is a process for manufacturing a plated product ( 1 ) comprising a support part in steel ( 2 ) and an anticorrosion metallic coating ( 3 ), characterized in that the anticorrosion coating ( 3 ) is fixed on the support part ( 2 ) by controlled-atmosphere brazing, in particular by vacuum brazing. The process according to the invention makes it possible to fix solidly an anticorrosion coating with a thickness smaller than 1 mm on a steel plate.

1 . A process for manufacturing a plated product comprising a support part in steel and an anticorrosion metallic coating, said process comprising at least one brazing operation under controlled atmosphere, utilizing at least one brazing material, in such a way as to establish a mechanical bond between at least one defined part of the support and at least one defined part of the coating.  
     
     
         2 . The manufacturing process of  claim 1 , wherein the brazing operation comprises bringing said defined parts closer together in such a way as to obtain a space D less than 0.1 mm.  
     
     
         3 . The manufacturing process of  claim 1 , wherein the brazing operation is effected under vacuum.  
     
     
         4 . The manufacturing process of  claim 3 , wherein the residual pressure of said vacuum is less than 10 −4  mbar.  
     
     
         5 . The manufacturing process of  claim 3 , wherein said brazing operation comprises: 
 interposing at least one brazing material between the steel support part and the anticorrosion coating, in such a way as to form an initial assembly;    optionally, applying a plating pressure on said initial assembly;    introducing the initial assembly into a vacuum chamber provided with means of heating;    formation of a vacuum in said chamber;    heating of said assembly up to a temperature at least equal to the brazing temperature of said brazing material.    
     
     
         6 . The manufacturing process of  claim 1 , wherein the brazing operation is effected under inert gas.  
     
     
         7 . The manufacturing process of  claim 6 , wherein the inert gas is selected from the group comprising rare gases, nitrogen and mixtures thereof.  
     
     
         8 . The manufacturing process of  claim 6 , wherein said brazing operation comprises: 
 interposing at least one brazing material between the steel support part and the anticorrosion coating, in    such a way as to form an initial assembly;    possibly, applying a plating pressure on said initial assembly;    introducing the initial assembly into a controlled-atmosphere chamber provided with means of heating;    replacing the atmosphere in said chamber with an inert gas;    heating of said assembly up to a temperature at least equal to the brazing temperature of said brazing material.    
     
     
         9 . The manufacturing process of  claim 1 , further comprising at least one treatment selected from the group comprising the chemical treatments, the electrochemical treatments, the physico-chemical treatments, the mechanical treatments and the combinations thereof.  
     
     
         10 . The manufacturing process of  claim 1 , further comprising depositing at least one layer capable of improving the tying of the brazing material.  
     
     
         11 . The manufacturing process of  claim 10 , wherein said layer is metallic.  
     
     
         12 . The manufacturing process of  claim 10 , wherein said depositing is effected by chemical means, electrolytic means or in vapor phase.  
     
     
         13 . The manufacturing process of  claim 1 , wherein the thickness of said coating is less than 1 mm.  
     
     
         14 . The manufacturing process of  claim 1 , wherein the thickness of said coating is less than 0.5 mm.  
     
     
         15 . The manufacturing process of  claim 1 , wherein said coating is in tantalum or an alloy of tantalum.  
     
     
         16 . The manufacturing process of  claim 15 , wherein the brazing material is a material containing nickel and boron.  
     
     
         17 . The manufacturing process of  claim 15 , wherein the brazing material is a silver-based material containing lithium, copper, aluminium, zinc and/or tin.  
     
     
         18 . The manufacturing process of  claim 1 , wherein said coating is in titanium or an alloy of titanium.  
     
     
         19 . The manufacturing process of  claim 18 , wherein the brazing material is an alloy with a titanium base.  
     
     
         20 . The manufacturing process of  claim 18 , wherein the brazing material is a silver-based material containing lithium, copper, aluminium, zinc and/or tin.  
     
     
         21 . The manufacturing process of  claim 1 , wherein said coating is in zirconium or an alloy of zirconium.  
     
     
         22 . The manufacturing process of  claim 21 , wherein the brazing material is an alloy with a base of zirconium, copper or nickel.  
     
     
         23 . The manufacturing process of  claim 21 , wherein the brazing material is a silver-based material containing lithium, copper, aluminium, zinc and/or tin.  
     
     
         24 . The manufacturing process of  claim 1 , wherein the brazing material comes in the form of powder, a sheet or a mesh.  
     
     
         25 . The manufacturing process of  claim 1 , wherein said steel is a chromium steel.  
     
     
         26 . The manufacturing process of  claim 1 , wherein the difference between the thermal expansion coefficient of said steel and the thermal expansion coefficient of said anticorrosion coating is less than 20%.  
     
     
         27 . The manufacturing process of  claim 1 , wherein said support part comes in the form of a plate or sheet.  
     
     
         28 . The manufacturing process of  claim 1 , wherein said coating comes in the form of a plate or sheet.  
     
     
         29 . The manufacturing process of any one of  claims 1  to  28 , wherein said plated product is an assembly part or an element of a chemical device.