Spray arc, short-circuiting and pulsed arc transfers are the three options of transfers for MIG welding on stainless steel.  The characteristics of the material to be welded will determine which transfer option is best suited for that particular project.  

• When MIG welding on stainless, you usually have three choices of transfer depending on your equipment: spray-arc, short-circuiting, or pulsed-arc transfer.
• Spray-Arc Transfer: Electrode diameters as great as 1/16-in., but usually 0.045", 0.035", and 0.030", are used with relatively high currents to create the spray-arc transfer.
• DCEP (Direct Current Electrode Positive) is used for most stainless-steel welding. A 1or 2% argon-oxygen mixture is recommended for most stainless steel spray arc welding.
• Short-Circuiting Transfer: Power supply units with slope, voltage, and inductance controls are recommended for the welding of stainless steel with short-circuiting transfer. Inductance, in particular, plays an important part in obtaining proper puddle fluidity. 
• Pulsed-Arc Transfer: The pulsed arc process is normally a process wherein one small drop of molten metal is transferred across the arc for each high current pulse of weld current.
• The high current pulse must be of sufficient magnitude and duration to cause at least one small drop of molten metal to form and be propelled by the pinch effect from the end of the wire to the weld puddle.
• Gases for pulsed arc welding are argon plus 1% oxygen, the same as used for spray arc welding.
• The shielding gas recommended for short-circuiting welding of stainless-steel contains 90% helium, 7.5% argon, and 2.5% carbon dioxide.

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