Aluminum alloy welding wire

Abstract

A composition for welding or brazing aluminum comprises silicon (Si) and magnesium (Mg) along with aluminum in an alloy suitable for use in welding and brazing. The Si content may vary between approximately 4.7 and 10.9 wt %, and the Mg content may vary between approximately 0.15 wt % and 0.50 wt %. The alloy is well suited for operations in which little or no dilution from the base metal affects the Si and/or Mg content of the filler metal. The Si content promotes fluidity and avoids stress concentrations and cracking. The Mg content provides enhanced strength. Resulting joints may have a strength at least equal to that of the base metal with little or no dilution (e.g., draw of Mg). The joints may be both heat treated and artificially aged or naturally aged.

1 . A composition for forming weld or braze joints, comprising:
 silicon in a weight percent of between approximately 4.7% inclusive and 10.9% inclusive;   magnesium in a weight percent of between approximately 0.15% inclusive and 0.50% inclusive; and   a remainder of aluminum and trace components.   
     
     
         2 . The composition of  claim 1 , comprising silicon in a weight percent of between approximately 4.7% inclusive and 8.0% inclusive. 
     
     
         3 . The composition of  claim 2 , comprising silicon in a weight percent of between approximately 5.0% inclusive and 6.0% inclusive. 
     
     
         4 . The composition of  claim 1 , comprising magnesium in a weight percent of between approximately 0.15% inclusive and 0.30% inclusive. 
     
     
         5 . The composition of  claim 4 , comprising magnesium in a weight percent of between approximately 0.31% inclusive and 0.50% inclusive. 
     
     
         6 . The composition of  claim 1 , comprising one or more trace components including iron, copper, manganese, zinc, titanium and beryllium. 
     
     
         7 . The composition of  claim 6 , wherein the total weight percent of the trace components does not exceed approximately 0.15 wt % of the composition. 
     
     
         8 . The composition of  claim 1 , wherein the composition comprises a spooled or linear wire or rod. 
     
     
         9 . The composition of  claim 1 , wherein the composition comprises a brazing component. 
     
     
         10 . The composition of  claim 10 , wherein the brazing component comprises such as brazing rings or paste. 
     
     
         11 . The composition of  claim 1 , wherein the composition comprises a cladding alloy for cladding aluminum base alloys for brazing to aluminum or aluminum alloy base metal components. 
     
     
         12 . The composition of  claim 11 , wherein the wire or rod has a nominal diameter of 0.023 inches, 0.030 inches, 0.035 inches, 0.040 inches, 0.047 inches, 0.062 inches, 0.094 inches, 0.125 inches, 0.156 inches, 0.187 inches, or 0.250 inches. 
     
     
         13 . A filler metal product for welding or brazing, comprising:
 a spooled or linear wire or rod comprising an alloy of silicon in a weight percent of between approximately 4.7% inclusive and 10.9% inclusive, magnesium in a weight percent of between approximately 0.15% inclusive and 0.50% inclusive, and a remainder of aluminum and trace components.   
     
     
         14 . The product of  claim 13 , comprising silicon in a weight percent of between approximately 4.7% inclusive and 8.0% inclusive. 
     
     
         15 . The product of  claim 14 , comprising silicon in a weight percent of between approximately 5.0% inclusive and 6.0% inclusive. 
     
     
         16 . The product of  claim 13 , comprising magnesium in a weight percent of between approximately 0.15% inclusive and 0.30% inclusive. 
     
     
         17 . The product of  claim 16 , comprising magnesium in a weight percent of between approximately 0.31% inclusive and 0.50% inclusive. 
     
     
         18 . A method for making a composition for forming weld or braze joints, comprising:
 obtaining an alloy comprising silicon in a weight percent of between approximately 4.7% inclusive and 10.9% inclusive, magnesium in a weight percent of between approximately 0.15% inclusive and 0.50% inclusive, and a remainder of aluminum and trace components; and   forming the alloy into a cast, extruded, drawn, rolled or linear wire or rod suitable for welding or brazing and cladding on braze-clad sheet.   
     
     
         19 . The method of  claim 18 , wherein the wire or rod has a nominal diameter of 0.023 inches, 0.030 inches, 0.035 inches, 0.040 inches, 0.047 inches, 0.062 inches, 0.094 inches, 0.125 inches, 0.156 inches, 0.187 inches, or 0.250 inches. 
     
     
         20 . A method for forming a weld or braze joint, comprising:
 melting or metallurgically bonding at least a portion of a work piece base metal;   adding or bonding to the base metal a filler metal comprising an alloy of silicon in a weight percent of between approximately 4.7% inclusive and 10.9% inclusive, magnesium in a weight percent of between approximately 0.15% inclusive and 0.50% inclusive, and a remainder of aluminum and trace components; and   allowing the resulting weld or braze joint to solidify.   
     
     
         21 . The method of  claim 20 , wherein melting the base metal and adding the filler metal is performed by a welding operation that includes striking an arc between the base metal and a wire or rod comprising the filler metal. 
     
     
         22 . The method of  claim 21 , wherein the welding operation comprises a metal inert gas welding operation. 
     
     
         23 . The method of  claim 22 , wherein the welding operation comprises a pulsed waveform welding process. 
     
     
         24 . The method of  claim 21 , wherein the welding operation comprises a stick welding operation. 
     
     
         25 . The method of  claim 20 , wherein melting the base metal or metallurgical bonding to the base metal and adding the filler metal is performed by an operation that includes heating the base via a heat source and adding the filler metal by hand, preformed shape such as a brazing ring or as cladding on brazing sheet. 
     
     
         26 . The method of  claim 25 , wherein the operation comprises a tungsten inert gas welding process, plasma gas welding process, electron beam welding process, laser beam welding process, furnace brazing process, or torch brazing process. 
     
     
         27 . The method of  claim 20 , comprising heat treating a structure comprising the weld or braze joint. 
     
     
         28 . The method of  claim 20 , comprising aging a structure comprising the weld or braze joint. 
     
     
         29 . The method of  claim 20 , comprising performing a plurality of successive passes in which the base metal and/or preceding passes of the filler metal are melted and additional filler metal is deposited. 
     
     
         30 . The method of  claim 29 , wherein during at least one successive pass substantially all magnesium in the respective pass is provided by the filler metal. 
     
     
         31 . The method of  claim 20 , wherein in a structure comprising the weld or braze joint, the weld or braze joint has a strength at least equal to the base metal. 
     
     
         32 . A welded or brazed structure made by the method of  claim 17 .