TIG Gases

Carbon Steel

MetalGaugeMode of Metal TransferRecommended GasComments
Carbon SteelALLManualArgonBest puddle control, especially for out of position welding
Carbon SteelALLMechanizedHeliStar A-75, A-50High speeds; lower gas flows than with pure helium
Carbon SteelALLMechanizedHeliumHigher speeds than obtained with argon; improved penetration

Stainless Steel

Stainless Steel ALLManual ArgonExcellent puddle control, controlled penetration
Stainless Steel ALLMechanizedArgonExcellent control of penetration on light gauge materials
Stainless Steel ALLMechanizedHeliStar A-75, A-50Higher heat input, higher welding speeds possible
Stainless Steel ALLMechanizedHydroStar H2, H-5Minimizes undercutting; produces desirable weld contour at low current levels, requires lower gas flows, ideal as a back purge gas on 300 series stainless steel

Aluminum

AluminumALLManual ArgonBest arc starting, good cleaning action and weld quality; lower gas consumption
AluminumALLManualHeliStar A-75Higher welding speeds, greater weld penetration than argon
AluminumALLMechanizedHeliStar A-75, A-50Good weld quality, lower gas flow required with straight helium, improved penetration
AluminumALLMechanizedHelium (dcsp)Deepest weld penetration and greatest weld speeds; can provide cleaning action for aluminum and magnesium welding

Nickel and Copper Nickel Alloys

Nickel and Cu/Ni AlloysALLManualArgonExcellent puddle control, penetration and bead contour on thin gauge metal
Nickel and Cu/Ni AlloysALLMechanizedHeliStar A-75, A-50Higher heat input to offset high heat conductivity of heavier gauges, faster travel speeds
Nickel and Cu/Ni AlloysALLMechanizedHeliumHighest heat input for sufficient welding speed on heavy metal sections