Aluminium alloy brazing material

Abstract

Disclosed is an aluminium alloy brazing material which is substantially lithium-free and calcium-free, and has the composition, in weight percent: Si 5.0 to 14.0; Fe 0.1 to 0.7; Mn 0.2 to 1.5; Mg max. 2.0; Zn max 1.0; optionally a wetting agent as alloying element up to 1%, and balance Al and inevitable impurities.

1 . An aluminium alloy brazing material which is substantially lithium-free and calcium-free, and comprising the composition, in wt. %:  
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                     
                 
                     
                   Si 
                   5.0 to 14.0 
                 
                     
                   Fe 
                   0.1 to 0.7 
                 
                     
                   Mn 
                   0.2 to 1.5 
                 
                     
                   Mg 
                   max. 2.0 
                 
                     
                   Zn 
                   max 1.0, and 
                 
                     
                     
                 
                     
                     
                 
             
                
                
               
               
                
                
                
                
                
                
                
               
            
           
         
         optionally a wetting agent as alloying element of at most 1%,  
         the balance Al and inevitable impurities.  
       
     
     
         2 . An aluminium alloy brazing material according to  claim 1 , wherein the alloy Mn/Fe ratio in weight percent is at least 1/1.  
     
     
         3 . An aluminium alloy brazing material according to  claim 1 , wherein the alloy Mn/Fe ratio in weight percent is at least 2/1.  
     
     
         4 . An aluminium alloy brazing material according to  claim 1 , having an intermetallic phase containing Mn and Fe in a ratio of Mn/Fe in weight percent of at least 0.4/1.  
     
     
         5 . An aluminium alloy brazing material according to  claim 1 , having an intermetallic phase containing Mn and Fe in a ratio of Mn/Fe in weight percent of at least 0.5/1.  
     
     
         6 . An aluminium alloy brazing material according to  claim 1 , having an intermetallic phase containing Mn and Fe in a ratio of Mn/Fe in weight percent of at least 0.7/1.  
     
     
         7 . An aluminium alloy brazing material according to  claim 1 , wherein the Si-content is in a range of 7.0 to 12.0%.  
     
     
         8 . An aluminium alloy brazing material according to  claim 1 , wherein the Mn-content is in a range of 0.3 to 1.0%.  
     
     
         9 . An aluminium alloy brazing material according to  claim 1 , wherein the Mn-content is in a range of 0.4 to 1.0%.  
     
     
         10 . An aluminium alloy brazing material according to  claim 1 , wherein the Mn-content is in a range of 0.4 to 0.8%.  
     
     
         11 . An aluminium alloy brazing material according to  claim 1 , wherein the Mg-content is in a range of up to 1%.  
     
     
         12 . An aluminium alloy brazing material according to  claim 1 , wherein the Mg-content is in a range of up to 0.4%.  
     
     
         13 . An aluminium alloy brazing material according to  claim 1 , wherein the Zn-content is in a range of up to 0.5%.  
     
     
         14 . An aluminium alloy brazing material according to  claim 1 , wherein the Fe-content is in the range of 0.1 to 0.6%.  
     
     
         15 . An aluminium alloy brazing material according to  claim 1 , wherein the Fe-content is in the range of 0.2 to 0.6%.  
     
     
         16 . An aluminium alloy brazing material according to  claim 1 , wherein a wetting agent as alloying element is present in a range of up to 0.8%.  
     
     
         17 . An aluminium alloy brazing material according to  claim 1 , wherein the wetting agent is selected from the group consisting of lead, bismuth, antimony, tin, silver, thallium, indium, and any mixture thereof.  
     
     
         18 . An aluminium alloy brazing material according to  claim 1 , wherein the material is substantially sodium-free.  
     
     
         19 . An aluminium alloy brazing material according to  claim 1 , wherein the material is substantially beryllium-free.  
     
     
         20 . A member suitable for brazing having a base of aluminium or aluminium alloy and a clad layer on said base having a lower melting point than said base, wherein said clad layer is an aluminium alloy brazing material according to  claim 1 .  
     
     
         21 . A brazed assembly comprising at least two members joined by an aluminium alloy brazing material according to  claim 1 .  
     
     
         22 . A brazed assembly according to  claim 21 , wherein the brazing material is in the form of a clad layer on one of said members or a fillet joining said two members.  
     
     
         23 . An aluminium alloy brazing material which is substantially lithium-free and calcium-free, and comprising the composition, in wt. %:  
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                     
                 
                     
                   Si 
                   5.0 to 14.0 
                 
                     
                   Fe 
                   0.1 to 0.7 
                 
                     
                   Mn 
                   0.2 to 1.5 
                 
                     
                   Mg 
                   max. 2.0 
                 
                     
                   Zn 
                   max 1.0, and 
                 
                     
                     
                 
                     
                     
                 
             
                
                
               
               
                
                
                
                
                
                
                
               
            
           
         
         the balance Al and inevitable impurities.  
       
     
     
         24 . An aluminium alloy brazing material according to  claim 1 , further comprising a wetting agent as alloying element of at most 1%.