NODULARIZING CATALYST FOR CAST IRON AND METHOD OF MAKING SAME

摘要

NODULARIZING CATALYST FOR CAST IRON AND METHOD OF MAKING SAME An improved catalyst is disclosed for making spheroidal graphitic cast iron, the catalyst being in the form of a solid impervious and brittle block but severed from a sheet stock having a predetermined grid pattern of perforations or notches along at least one surface of said sheet stock. The block is substantially devoid of segregation and oxide interiorally thereof; the thickness of said block is increased over that capable of being produced by the prior art in the as-cast condition and yet devoid of segregation. The method of making such block comprises casting the molten catalyst into shallow closed pans, the cover for said pans carrying a pattern of ribs or projections, the cover and pan cooperating to define a selected configuration for an as-cast sheet stock. The resulting cast product can be manually or automatically broken along any desired module, defined by said grid pattern, to suit a variety of in plant casting applications particularly utilizing in-the-mold nodularizing treatment. The latter method places a nodularizing catalyst in a recess or reaction chamber defined within the gating system of a mold, whether constructed of bonded sand or pre-cast refractory.