Superior
corrosion
resistance
than a 316.
Good Resistance
to stress
corrosion
cracking in
a chloride
environment.
Duplex
materials
have improved
over the last
decade; further
additions
of Nitrogen
have been
made improving
weldability.
Because
of the complex
nature of
this material
it is important
that it is
sourced from
good quality
steel mills
and is properly
solution annealed.
Castings and
possibly thick
sections may
not cool fast
when annealed
causing sigma
and other
deleterious
phases to
form.
The
material work
hardens if
cold formed;
even the strain
produced from
welding can
work harden
the material
particularly
in multi pass
welding. Therefore
a full solution
anneal is
advantageous,
particularly
if low service
temperatures
are foreseen.
The
high strength
of this material
can make joint
fit up difficult.
Usable
temperature
range restricted
to, -50 to
280°C
Used
in Oil &
Natural Gas
production,
chemical plants
etc
