KappAloy™ Tin-Zinc Solders for Aluminum to Aluminum and Copper

KappAloy™ Tin-Zinc solder is designed specifically for Aluminum-to-Aluminum and Aluminum-to-Copper soldering. It has good corrosion resistance and tensile strength. Melting range begins at 390F (199C) and lies between soft solder and silver brazing alloys, thereby avoiding damage to critical electronics and substrate deformation and segregation. Forms are available for dip and furnace soldering, torch and iron, spray guns and rub tinning.

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Benefits and Uses

Used to join electrical/electronic wires and Copper fittings, heating panels, high voltage components & sound equipment. Used in spray wire form to spray molds, patterns, capacitors, trophies, and for ultrasonic soldering.

KappAloy9™ - 91%Sn - 9%Zn - 390F (199C) eutectic alloy is the best solder for Aluminum wire to Copper busses or Copper wire to Aluminum busses or contacts. Its low eutectic melting point minimizes heating of critical electrical/electronic parts.

KappAloy15™ - 85%Sn - 15%Zn has a wider plastic range of 390F - 500F (199C - 260C). This makes it ideal for hand soldering Aluminum plates and parts, allowing manipulation of the parts as the solder cools.

Other Tin Zinc alloys - 80%Sn - 20%Zn, 70%Sn - 30%Zn and 60%Sn - 40%Zn are used extensively in spray wire form for capacitors and other electronic parts. Benefits include higher tensile strength and higher temperature tolerances than KappAloy9tm.

The following chart represents Kapp Alloys standard Tin-Zinc alloys. Many factors, such as materials, temperature, and method of application determine the solder joint strength and characteristics. Call Kapp for engineering assistance to discuss your specific needs. We recommend testing appropriate alloys in your specific application to ensure suitability. Samples of Kapp alloys are always available upon request.

Dont forget to look at Cadmium/Zinc Solders and Alumite™ for Aluminum Soldering Needs.

Composition Temperature
Sn Zn Pb Cd Ag Cu Sb RFQ Wire Ribbon 1/4" x14" 1/8" x18" Handy Vials
100             232 449 950 X X X X X
91 9           199-199 390-390 121 X X X    
85 15           199-260 390-500 124 X X X X X
80 20           199-288 390-550 125 X X X X X
70 30           199-316 390-600 128 X X X X X
60 40           199-343 390-650 129 X   X X  
Sn=Tin, Zn=Zinc, Pb=Lead, Cd=Cadmium, Ag=Silver, Cu=Copper, Sb=Antimony


  • Diameters from .031" (1/32" and .8mm) to .187" (3/16" and 4.75mm).
  • Spool sizes: 1 lb., 5 lbs., and 25 lbs. Also available in convenient 18" X 1/8" rods.
  • spray wire Pay-out Paks: 250 lbs. or 500 lbs* of reverse wound continuous wire

*Kapp does not recommend 500 lbs. payout paks for wire sizes smaller than 1/8" (.125) due to wire deformation in transit


  • RegBar nominally 1 lb. each - Molds are 13.5" L x 0.75" W x 0.5" D with oval ends.
  • 2 Lb. Bar - 2+ lbs. each - Molds are 10.5" L x 1" D, 1.5" W tapering to 1".
  • Notch Bar - 6+ lbs. each - Molds are 11" L x 2.25" W x 1.25" D with 4 notches, 5 sections per bar.