8
Non-Ferrous Materials
ALUMINUM & ALUMINUM ALLOYS
The principal elements used to produce
aluminum alloy wire electrodes are magnesium, manganese, zinc,
silicon and copper. The primary reason
for adding these elements is to increase the strength of pure
aluminum. However, corrosion resistance
and weldability are also major considerations. Each wire contains
additions of several alloying elements
to improve the weld properties, and is designed to weld a given type
of aluminum. The most popular wires
are the magnesium-containing 5356 and the silicon-containing 4043.
The manner in which elements are combined
to form the various wire electrodes used for mig welding of
aluminum appear in Table
5-4*. This table lists the chemical requirements and designations for
all aluminum wires
covered by the American Welding Society Specification A5.10. There are no mechanical
property requirements
for the weld metal. The
choice of aluminum electrodes is influenced by the same consider- ations previously
listed. Again, experience
of the welding industry has made selection straightforward. Table
5-5* lists the wire electrodes suitable
for welding various base plate materials. Wire-workpiece combinations not appearing
in this table will
usually yield inferior welds.
