CAST IRON MEMBER HAVING RESISTANCE TO CORROSION BY FORMIC ACID

摘要

PURPOSE:To provide improved resistance to corrosion by formic acid necessary for a methanol-fueled engine to a cast iron base material by forming an Fe-Si alloyed layer having a prescribed concn. of Si on the surface of the base material. CONSTITUTION:An Si coating layer is formed on the surface of a cast iron base material by thermally spraying Si powder on the surface. The coating layer and a part of the base material are then melted by projecting high density energy such as laser beams or electron beams to alloy a part of the cast iron with the coating component. The average concn. of Si in the resulting alloyed layer is regulated to 10-20wt%.