PURPOSE: The titled casting material wherein an anodic wing is hardly deformed even if a grinding amount is increased during grinding processing of anodic material of magnetron, capable of removing easily embedded materials after processing, obtained by adding a filler and a thermoplastic resin to an epoxy resin containing a curing agent.

CONSTITUTION: Preferably 70W30pts.wt. filler (e.g., calcium carbonate, sawdust, etc.) and preferably 5W20pts.wt. thermoplastic resin (e.g., polyester, etc.) are added to preferably 30W70pts.wt. epoxy resin (e.g., bisphenol A epoxy resin, etc.) containing a curing agent (e.g., aliphatic polyamine, etc.), to give the desired casting material.