17
*Deoxidized
Copper—Bare Filler Wire Tungsten
Inert Gas or Carbon Arc Application General
Characteristics A
bare filler material used for TIG and carbon arc brazing and welding.
Typical Applications
High purity weld deposits when fabricating
deoxidized copper or limited use on electrolytic tough pitch copper. lt
can also be used to join copper to
steel or overlay them. Welds with this alloy have high electrical conductivity
and excellent
corrosion resistance. Beryllium copper is not recommended for welding because
of toxicity. Qualities
Tensile strength
—35,000 psi (24.61 kgs/mm2)
Elongation in 2"
—40-50% Hardness
—25 to 40 Rockwell F
Color Match
—excellent on copper
Meets Specification AWS A5.7 (ER-Cu)
Procedures Base
metal must be free of oxides and clean. Preheating is very important. The proper
temperatures must be maintained
while welding if dense, porosity free welds are desired. TIG welds are made with
direct current straight polarity
and either 75% Helium—25% Argon, 100% Argon, or 100% Helium gases. Copper
base metal should be preheated
to 400°-1000°F (204°-538°C). Due to heat dissipation, the
root width and groove angles are larger than for
steel. Peening is not necessary, but will help reduce stresses and distortion.
