GTAW · Stainless steel

ER2209

The matching filler for 22 chromium duplex stainless, deliberately over-alloyed in nickel so the deposit does not solidify with too much ferrite.

What the designation means

ER
Classified as both an electrode and a hand fed filler rod.
22
Nominally 22 percent chromium, the level that gives duplex stainless its corrosion resistance.
09
Nominally 9 percent nickel, deliberately higher than the base metal so the weld holds enough austenite after fast cooling.

At a glance

ProcessGTAW
FamilyStainless steel
PositionsAll positions
PolarityDCEN
ShieldingWelding grade argon at the torch, with argon or an argon-nitrogen blend as backing to protect the root and hold the phase balance
Minimum tensile strength100 ksi

Typical uses

  • Duplex stainless piping and vessels in offshore oil and gas
  • Seawater and desalination process equipment
  • Chemical plant handling chloride bearing fluids

How it runs

  • High strength deposit, well above the standard austenitic stainless fillers
  • Heat input and interpass temperature must be held within a window to keep the ferrite and austenite balanced
  • Nitrogen in the backing gas helps preserve austenite at the root
  • Puddle is sluggish and the bead is duller and more magnetic than an austenitic deposit

Storage and handling

Store in the sealed tube in a clean dry area and keep the rods free of carbon steel dust that would contaminate the deposit.

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