Modified flux system

Abstract

A method of manufacturing a flux cored electrode is described that includes a titanium oxide based flux system having a low water content, which resists moisture absorption, and which reduces the amount of impurities transferred to a weld metal comprising: providing titanium dioxide, the titanium dioxide including purified titanium dioxide; providing a solution of colloidal metal oxide, the colloidal metal oxide having an average particle size of less than about 800 nm; mixing together the titanium dioxide and solution of colloidal metal oxide; and, drying the mixture at a temperature of at least about 400° C. for at least about 30 minutes until a moisture content of the mixture is less than about 1%; and, forming a metal electrode sheath so as to include the mixture in a core of the metal electrode sheath. The purified titanium oxide includes little or no impurities that can act as nucleation sites for carbide formation in a weld metal.

What is claimed is: 
     
         1 . A method of manufacturing a flux cored electrode that includes a titanium oxide based flux system having a low water content, which resists moisture absorption, and which reduces the amount of impurities transferred to a weld metal comprising:
 providing titanium dioxide, said titanium dioxide including purified titanium dioxide;   providing a solution of colloidal metal oxide, said colloidal metal oxide having an average particle size of less than about 800 nm;   mixing together said titanium dioxide and solution of colloidal metal oxide; and,   drying said mixture at a temperature of at least about 400° C. for at least about 30 minutes until a moisture content of said mixture is less than about 1%; and,   forming a metal electrode sheath so as to include said mixture in a core of said metal electrode sheath.   
     
     
         2 . The method as defined in  claim 1 , wherein
 said metal electrode sheath includes a majority of iron.   
     
     
         3 . The method as defined in  claim 1 , wherein
 said mixture comprising about 10-40 weight percent of the total weigh of said flux cored electrode.   
     
     
         4 . The method as defined in  claim 2 , wherein
 said mixture comprising about 10-40 weight percent of the total weigh of said flux cored electrode.   
     
     
         5 . The method as defined in  claim 1 , including the step of
 grinding said dried mixture to an average particle size of about 40-200 mesh.   
     
     
         6 . The method as defined in  claim 4 , including the step of
 grinding said dried mixture to an average particle size of about 40-200 mesh.   
     
     
         7 . The method as defined in  claim 1 , wherein
 said colloidal metal oxide includes silica.   
     
     
         8 . The method as defined in  claim 6 , wherein
 said colloidal metal oxide includes silica.   
     
     
         9 . The method as defined in  claim 1 , including the step of
 providing metal agent and mixing said metal agent with said titanium dioxide and solution of colloidal metal oxide.   
     
     
         10 . The method as defined in  claim 8 , including the step of
 providing metal agent and mixing said metal agent with said titanium dioxide and solution of colloidal metal oxide.   
     
     
         11 . The method as defined in  claim 1 , including the step of
 providing binder and mixing said binder with said titanium dioxide and solution of colloidal metal oxide, said binder including metal silicate.   
     
     
         12 . The method as defined in  claim 10 , including the step of
 providing binder and mixing said binder with said titanium dioxide and solution of colloidal metal oxide, said binder including metal silicate.   
     
     
         13 . The process of  claim 1  wherein said titanium oxide based flux system comprises: 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   TiO 2  (at least 5% purified) 
                   2-70%, 
                 
                     
                   colloidal metal oxide 
                   1-40%, 
                 
                     
                   slag forming agent 
                   1-60%, and 
                 
                     
                   metal alloying agent 
                   0-80%. 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
                
               
            
           
         
       
     
     
         14 . The process of  claim 13  wherein said titanium oxide based flux system comprises: 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   TiO 2  (at least 20% purified) 
                   3-60%, 
                 
                     
                   colloidal metal oxide 
                   1-30%, 
                 
                     
                   slag forming agent 
                   0-50%, and 
                 
                     
                   metal alloying agent 
                   0-70%. 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
                
               
            
           
         
       
     
     
         15 . The process of  claim 14  wherein said titanium oxide based flux system comprises: 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   TiO 2  (at least 50% purified) 
                   5-40%, 
                 
                     
                   colloidal metal oxide 
                   1-25%, 
                 
                     
                   slag forming agent 
                   5-45%, and 
                 
                     
                   metal alloying agent 
                   0-50%. 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
                
               
            
           
         
       
     
     
         16 . The process of  claim 15  wherein said titanium oxide based flux system comprises: 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   TiO 2  (at least 90% purified) 
                   10-40%, 
                 
                     
                   colloidal metal oxide 
                    1-20%, 
                 
                     
                   slag forming agent 
                   10-40%, and 
                 
                     
                   metal alloying agent 
                    0-40%. 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
                
               
            
           
         
       
     
     
         17 . A method of manufacturing a flux cored electrode that includes a titanium oxide based flux system having a low water content, which resists moisture absorption, and which reduces the amount of impurities transferred to a weld metal comprising:
 providing titanium dioxide, said titanium dioxide including purified titanium dioxide;   providing a solution of colloidal metal oxide, said colloidal metal oxide having an average particle size of less than about 800 nm, said colloidal metal oxide includes silica;   mixing together said titanium dioxide and solution of colloidal metal oxide; and,   drying said mixture at a temperature of at least about 400° C. for at least about 30 minutes until a moisture content of said mixture is less than about 1%; and,   forming a metal electrode sheath so as to include said mixture in a core of said metal electrode sheath, wherein said sheath includes a majority of iron; and   said mixture comprising about 10-40 weight percent of the total weigh of said flux cored electrode, and   providing a binder and mixing said binder with said titanium dioxide and solution of colloidal metal oxide, said binder including metal silicate.   
     
     
         18 . The method as defined in  claim 17 , including the step of
 grinding said dried mixture to an average particle size of about 40-200 mesh.   
     
     
         19 . The process of  claim 18  wherein said titanium oxide based flux system comprises: 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   TiO 2  (at least 50% purified) 
                   5-40%, 
                 
                     
                   colloidal metal oxide 
                   1-25%, 
                 
                     
                   slag forming agent 
                   5-45%, and 
                 
                     
                   metal alloying agent 
                   0-50%. 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
                
               
            
           
         
       
     
     
         20 . The process of  claim 19  wherein said titanium oxide based flux system comprises: 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   TiO 2  (at least 90% purified) 
                   10-40%, 
                 
                     
                   colloidal metal oxide 
                    1-20%, 
                 
                     
                   slag forming agent 
                   10-40%, and 
                 
                     
                   metal alloying agent 
                    0-40%.