abstract |
Phenolic resin binder systems for sand molds, used in metal casting, which improve the quality of thermally reclaimed sand, are described. The substantial or complete elimination of calcium compounds (e.g., calcium stearate and calcium hydroxide, conventionally employed as a mold lubricant and a resin curing catalyst, respectively) allows the thermally reclaimed sand to be reused over multiple thermal reclamation cycles without the adverse effects previously encountered. |