MIG
SHIELDING GAS SELECTION GUIDE |
Metal |
Thickness in.
(mm) |
Recommended
Shielding Gas |
Advantages |
MIG SHORT
ARC |
Carbon Steel |
Up to 14 gauge
(0.1) |
92% Argon / 8%
CO2 |
Good burnthrough
and distortion control. Used also for spray arc welding |
|
14 gauge - 1/8
(3.2) |
75% Argon / 25%
CO2 88% Argon / 12% CO2 |
High welding
speeds without burnthrough. Minimum distortion and spatter. Best puddle control for out of
position welding. Provides best mechanical properties for any given wire |
|
Over 1/8 (3.2) |
75% Argon / 25%
CO2 88% Argon / 12% CO2 |
High welding
speeds without burnthrough. Minimum distortion and spatter. Best puddle control for out of
position welding. Provides best mechanical properties for any given wire |
|
|
50% Argon / 50%
CO2 |
Deep penetration;
spatter |
|
|
CO2 |
Deep penetration;
faster welding speeds; high spatter |
Stainless Steel |
Up to 14 gauge
(0.1) |
92% Argon / 8%
CO2 |
Good burnthrough
and distortion control. For use where corrosion resistance is not mandatory |
|
Over 14 gauge
(0.1) |
92% Argon / 8%
CO2 |
Good burnthrough
and distortion control. For use where corrosion resistance is not mandatory |
|
|
90% He 7.5% Ar
2.5% CO2 |
No effect of
corrosion resistance. Small heat-affected zone. No undercutting, minimum distortion. Good
bead shape and mechanical properties |
High Yield
Strength Steels |
Up to 14 gauge
(0.1) |
92% Argon / 8%
CO2 |
Good burnthrough
and distortion control. Used also for spray arc welding |
|
Over 14 gauge
(0.1) |
Argon - Hydrogen |
Excellent arc
stability, welding characteristics bead contour, little spatter, high impacts |
MIG SPRAY
ARC |
Carbon Steel |
All thicknesses |
95% Argon / 5%
O2 |
Improves droplet
rate and arc stability |
|
|
92% Argon / 8%
CO2 |
Produces a more
fluid and controllable weld puddle; good coalescence and bead contour. Minimizes
undercutting; permits high speeds |
Aluminum |
Up to 3/8 (12.7) |
Argon |
Best metal
transfer, arc stability and plate cleaning. Little or no spatter. |
|
Over 3/8 (12.7) |
Argon - Helium |
Higher heat input.
Produces more fluid puddle and flatter bead. Minimizes porosity. |
| |
|
Helium |
Highest heat input. Good for
mechanized welding. |
Low Alloy Steel |
Up to 3/32 (2.4) |
98% Argon / 2%
O2 |
Reduces
undercutting. Improves coalescence and bead contour. Good mechanical properties. |
|
Over 3/32 (2.4) |
92% Argon / 8%
CO2 |
Excellent arc and
weld characteristics. |
Stainless Steel |
All thicknesses |
99% Argon / 1%
O2 |
Good arc
stability. Produces a fluid and controllable weld puddle; good coalescence and bead
contour. Minimizes undercutting. |
|
|
98% Argon / 2%
O2 |
Can be used on
more sluggish alloys to improve puddle fluidity, coalescence and bead contour. |
Copper, Nickel &
Copper-Nickel alloys |
Up to 1/8 (3.2) |
Argon |
Good arc stability. |
|
Over 1/8 (3.2) |
Argon - Helium |
Higher heat input
of helium mixture offsets high heat conductivity of heavier gauges. |
| |
|
Helium |
Higher heat input and improved
penetration. |
Magnesium Titanium |
-- |
Argon |
Excellent cleaning
action. Provides more stable arc than helium-rich mixtures |
MIG CORED
WIRE |
| Carbon Steel |
All thicknesses |
CO2 |
Deep penetration. |
|
|
75% Argon / 25%
CO2 |
Low smoke and
spatter. Good puddle control. Bridges gaps |
Stainless Steel |
All thicknesses |
CO2 |
Deep penetration. |
|
|
75% Argon / 25%
CO2 |
Low smoke and
spatter. Good puddle control. Bridges gaps |
