Stainless steel strip coated with aluminium

Abstract

A coated stainless steel strip product with a dense and evenly distributed aluminum layer on one side or both sides of said strip is provided. Said layer consists of essentially pure aluminum, the thickness of said layer is maximally 15 μm, the tolerance of said layer is maximally +/−30% of the layer thickness, the Cr content of the steel strip substrate is at least 10%, and that the layer has such a good adhesion so that the coated steel strip can be bent 180° over a radius maximally equal to the thickness of said strip without showing any tendency to flaking or the like. The Al-coated strip product is suitable for applications in environments with high humidity or in wet conditions, such as outdoor life applications, sports and sea-life, household and personal care.

1 . A coated stainless steel strip product includes a dense and evenly distributed layer on one side or both sides of a strip substrate, 
 wherein said layer consists of essentially pure aluminum and is applied directly on to the strip substrate, a thickness of said layer is maximally 15 μm, the a tolerance of said layer is maximally +/−30% of the layer thickness, a Cr content of the strip substrate is at least 10%, and    wherein the layer has such a good adhesion so that the coated steel strip can be bent 180° over a radius maximally equal to the thickness of said coated steel strip without showing any tendency to flaking or the like.    
   
   
       2 . Product according to  claim 1 , wherein a thickness of the strip substrate is between 0.15 mm and 3.0 mm.  
   
   
       3 . Product according to  claim 1 , wherein the strip substrate is ferritic stainless steel, hardenable chromium steel, austenitic stainless steel, duplex stainless steel, or precipitation hardenable stainless steel.  
   
   
       4 . Product according to  claim 1 , wherein the layer has a multi-layer constitution of up to 10 layers.  
   
   
       5 . Product according to  claim 4 , wherein each individual layer has a thickness of between 0.1 to 8 μm.  
   
   
       6 . Product according to  claim 5 , wherein the layer has a multi-layer constitution of individual layers of different metallic coatings and where at least one layer consists of essentially pure aluminum.  
   
   
       7 . A product according to  claim 1 , wherein the product is suitable for use in anti-corrosive applications acting as a sacrificial anode.  
   
   
       8 . A product according to  claim 1 , wherein the product is suitable for cost efficient and productive manufacturing of anti-corrosive components in applications occasionally used in environments with high humidity or in wet conditions.  
   
   
       9 . Method of manufacturing a coated stainless steel strip product according to  claim 1 , comprising: 
 producing said product in a continuous roll-to-roll process included in a strip production line, with a minimum strip speed of at least 5 meters per minute, and using electron beam evaporation comprising an etch chamber in-line.    
   
   
       10 . Product according to  claim 6 , wherein the different metallic coatings include coatings of Al, Ni, Ti, or Mo.  
   
   
       11 . Product according to  claim 8 , wherein environments with high humidity or wet conditions include outdoor life applications, sports and sea-life applications, household applications and applications for personal care.  
   
   
       12 . A coated stainless steel strip product comprising: 
 a strip substrate including at least 10 wt. % Cr; and    a coating on one side or both sides of said strip substrate, said coating including at least one layer consisting of essentially pure aluminum and said layer having a thickness of maximally 15 μm with a tolerance of said layer maximally +/−30% of the layer thickness,    wherein the coating has sufficient adhesion to the strip substrate such that the coated strip substrate can be bent 180° over a radius maximally equal to a thickness of said coated strip substrate without flaking.    
   
   
       13 . The coated stainless steel strip product according to  claim 12 , wherein the aluminum layer is applied directly onto the strip substrate.  
   
   
       14 . The coated steel strip product according to  claim 12 , wherein the coating is a multilayer coating including up to 10 individual layers and at least one of the individual layers in the multilayer coating consists of essentially pure aluminum.  
   
   
       15 . The coated steel strip product according to  claim 14 , wherein individual layers in the multilayer coating include layers of other metals selected from the group consisting of Ti, Ni, and Mo.  
   
   
       16 . A sacrificial anode formed from the coated steel strip product according to  claim 12 .  
   
   
       17 . An anti-corrosive component formed from the coated steel strip product according to  claim 12 .  
   
   
       18 . The anti-corrosive component according to  claim 17 , wherein the anti-corrosive component is suitable for use in environments with high humidity or wet conditions.  
   
   
       19 . The anti-corrosive component according to  claim 18 , wherein environments with high humidity or wet conditions include outdoor life applications, sports and sea-life applications, household applications and applications for personal care.  
   
   
       20 . A method of manufacturing a coated stainless steel strip product according to  claim 1 , comprising: 
 cleaning a stainless steel strip substrate in an etch chamber;    depositing a coating on one side or both sides of said strip substrate in a deposition chamber, said coating including at least one layer consisting of essentially pure aluminum and said layer having a thickness of maximally 15 μm with a tolerance of said layer maximally +/−30% of the layer thickness,    wherein cleaning and depositing occur in a continuous roll-to-roll process included in a strip production line, with a minimum strip substrate speed of at least 5 meters per minute, and using electron beam evaporation comprising an etch chamber in-line.    
   
   
       21 . The method according to  claim 20 , wherein depositing includes depositing with electron beam evaporation equipment under a reduced atmosphere with no addition of any reactive gas.  
   
   
       22 . The method according to  claim 20 , wherein cleaning includes ion-assisted etching of a surface of the substrate.  
   
   
       23 . The method according to  claim 20 , comprising a plurality of deposition chambers, each deposition chamber including electron beam evaporation equipment, 
 wherein said coating includes a multilayer having up to 10 individual layers, and    wherein at least one of the individual layers is the at least one layer consisting of essentially pure aluminum.