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All-State®
No. 31 and 31FC (Flux Cored) Alloy
for Brazing Thin Sheet Aluminum Torch
Application General
Characteristics All-State®
No. 31 and 31FC (flux cored) are special brazing alloys basically developed for
joining light gauge aluminum.
This alloy is very fluid and has a capillary action similar to silver brazing
alloys. Typical
Applications Recommended
for brazing thin sheets, extruded shapes and corner joints. Used extensively in
production and maintenance
brazing of aluminum furniture, truck and trailer bodies, window frames and aircraft
instruments. This alloy
is not recommended for the following grades of aluminum: 2011, 2014, 2017, 2024
and 7075. Qualities
Tensile strength
—up
to 30,000 psi (21.10 kgs/mm2) Working
temperature —1075°F
(579°C) Color
match
—-excellent
(will darken if anodized) Electrical
conductivity —good
Corrosion resistance
—good Procedures
Clean joint area. Recommended joint
clearance is .006" to .010" . All-State®
No. 31 Flux should be used with 31 bare,
either as a powder or mixed with water or alcohol to form a paste. No additional
flux is needed with 31FC as
it is flux cored. Heat with a carburizing torch flame, keeping torch in constant
motion until flux turns to a clear liquid.
Apply alloy. Continue to completely fill the joint. Use ample amounts of flux
to insure a strong, sound joint. Allow
the alloy to solidify and then remove flux by quenching and washing in hot water.
