Welding Cast Iron Vs Cast Steel. Cast iron is brittle and does not like tensile forces. Third remember cast iron has a slightly lower melting temperature than steel.
Bend and not break for the most part. On the other hand Cast steel contains less than 2 carbon. Cast is junk for small parts cheap crap.
Find out which one is best for.
Before welding it needs proper preheating. I worked for a foundry cast iron is not so hot. Cast Steel vs. Cast iron is brittle and does not like tensile forces.