Welding Cast Iron Using Tig. Tig welding cast iron using DC can be dirty and the cleaning action from alternating current helps maintain a clean puddle. The main reason why youve got to heat up your workpieces is to prop up carbon.
Arc TIG or MIG. However this usually comes with strong cautions. China has a high carbon content which may cause it to become brittle or harden irregularly both of which may cause unexpected breakage during the welding process.
With AC very little mixing of the cast iron occurs in the weld bead.
Another reason for using AC to tig weld cast iron is that less penetration and therefore less dilution of the cast iron base metal occurs. Cast Iron Welding Methods. I have had really good results tig welding cast iron using AC and Aluminum bronze filler rod. Another reason for using AC to tig weld cast iron is that less penetration and therefore less dilution of the cast iron base metal occurs.