For stainless steel, a welding apparatus of Argonoduga welding on direct current is perfect. For an experienced welder, this is the simplest job that should not cause any difficulties.
The same applies to the process of connecting products made of ordinary steel. With one difference: it is necessary to extremely carefully clean the edge of the joints. Also, to strengthen the resulting seam, it is better to use the filler wire.
The process of connecting copper and titanium parts is a little more complicated, in both cases only the most reliable protection of the molten bathtub from the formation of oxides is necessary.
In products made of cast iron, argon -drunk welding is used only to restore or repair worn spare parts. It is only necessary to use special filler materials that contain nickel.
The most difficult process is considered to be welded using argon -armed welding of aluminum elements. This metal has increased combustibility and instability to high temperatures. Also, this metal and its alloys require different stresses of the arc in the connection process. It will require maximum experience and rather big dexterity to maintain the desired temperature and do not burn the metal.