Abstract: Additives useful in producing foundry mold and core washes comprise either: a mixture of 66.75% to 80.05% of an organophilic clay and 19.95% to 33.25% of an alcohol soluble, hexane insoluble thermoplastic resin skin-forming agent; or 7.15% to 15.25% of an organophilic clay, 2.85% to 4.75% of the skin forming agent, and 80% to 90% of a refractory material having a particle size fo 200 mesh or finer.

Abstract: A method of insulating a shell mould for investment casting by adhering a particulate or fibrous insulator such as perlite, vermiculite or ceramic fibres to a shell mould by an adherent coating. In a preferred process the shell mould is first dipped into the adherent coating and the particulate insulator is applied to the mould through a stuccoing process. Multiple layers of insulation can be applied to the mould to vary the thickness of insulation as required.

Abstract: Disclosed is a foundry core wash made of a hydrocarbon solvent, fumaric acid resin, particulated calcium aluminate and a suspending agent. The core wash has particular utility for sand cores made with an inorganic binder used in pressurized die casting.

Abstract: A method for manufacturing a foundry core comprising mixing sand and a binder system containing a saccharide-containing material, glyoxal and an alkali halide.

Abstract: Disclosed is a method for reducing the amount of atmospheric moisture absorbed by foundry sand cores and molds. A wash coating composition is applied to the surfaces of foundry sand cores and molds. The coating comprises an organic liquid which can be chlorinated hydrocarbon, a suspending agent which can be clay, a vegetable gum or an amine-treated bentonite, a refractory powder which can be graphite, coke, mica, silica, alumina, magnesia, talc or zircon flour, and an organic polymer or copolymer, vinyl toluene/acrylate copolymer, styrene/acetylene copolymer, acrylate homopolymers and styrene/butadiene copolymers.

Abstract: An investment shell mold inhibited against reaction with molten titanium, zirconium and other reactive and refractory metals cast therein is made by investing a pattern with successive dip coats and stucco coats. The first dip coat includes a tungsten and/or molybdenum compound inhibitor-former which is reducible by hydrogen to metallic tungsten or molybdenum. After removal of the pattern, the green mold is dried and then pyrolyzed in an atmosphere of hydrogen under conditions predetermined to convert the inhibitor-former to metallic condition. This creates on the mold interface a coating of metallic molybdenum or tungsten which serves as a physical barrier, inhibiting reaction of a molten reactive or refractory metal subsequently cast in the mold, with the mold material and binder particles of the latter.

Abstract: An improved foundry facing sand is disclosed. The foundry facing sand comprises silica sand admixed therewith, in percent by weight of the silica sand, from about 0.8 to about 2 percent of a cellulose binder, from about 2 to about 6 percent of foundry clay, from about 3.5 to about 7 percent water, from about 1 to about 2.2 percent core oil, from about 0.3 to about 0.5 percent of a release agent-lubricant, and from about 0 to about 20 percent silica flour. The use of such foundry facing sand in green sand molds improves the quality and finish of finished castings and also does not detrimentally affect the permeability of system sand.