Iron welding

Iron is used in various forms. Thus, the welding of iron is one of the typical application areas. What has to be considered when welding iron, we have summarized in the following article for you.

Iron in its uses

Iron is the most abundant element on Earth after oxygen, silicon and aluminum. Due to its properties it is used in different form:

  • as pig iron
  • as cast iron
  • as alloy (high or low alloyed steel)

Welding process for welding iron

The iron workpieces to be processed are mostly steel alloys, followed by cast iron. In the home improvement sector, the following welding processes are suitable for welding iron:

  • Arc welding
  • Inert gas welding (MIG / MAG and TIG)
  • Autogenous welding

Electric and inert gas welding

Inert gas welding and arc welding are again the most commonly used. Electric welding ensures high mobility, but inert gas welding is cleaner. In constrained situations, both methods can be used equally, but more and more frequently welding companies use protective gas methods such as TIG welding (tungsten electrode with an inert shielding gas).

Weld iron with other metals and alloys

However, the joining of two pure iron parts is rarely made in the artisan sector. Rather we iron with an alloy, so steel, welded. A special feature is the welding of galvanized iron. The welding of stainless steel can be done not only with stainless steel, but of course with iron. Likewise, you can weld low-alloyed steels such as structural steel with iron.

The welding filler

When welding filler but you should then make sure that it has similar properties as the nobler metal or alloy to be welded. So use a welding filler that would be equivalent to steel alloy steel when welding iron.

Weldability of the different iron forms

Statements about the basic weldability of iron can also be made. In particular, iron with a low carbon content can be welded very well. Conversely, carbon-rich iron workpieces can be welded correspondingly poorer. Also impurities in the iron affect the weldability.

Not every iron can be welded

Low carbon would be, for example, wrought iron (ductile iron), rich in carbon stainless steels. Raw and cast iron liquefies when heated. Such iron can not be welded at all.

Tips & Tricks

Industry and craft use another welding process for iron - thermite welding. A fireclay mold is placed around the spot to be welded and filled with iron oxide and aluminum powder. An igniter of barium peroxide and magnesium for a violent exothermic reaction in which temperatures of about 2,400 degrees Celsius arise. The products resulting from the reaction are aluminum oxide and pure iron, which welds the two workpieces. Railway tracks are welded according to this principle. The process is known to last as long as most welding processes (since 1920).

Video Board: Cast Iron Welding Repair using Flux Core Wire