Foundry processes for the improvement of sand structure surfaces

摘要

1,132,612. Mould-lining and core-coating materials. ARCHER-DANIELS-MIDLAND CO. 8 Oct., 1965 [29 Oct., 1964], No. 42800/65. Heading B3F. [Also in Division C3] Sand-cores and -moulds are given a coating, 1-20 mils thick, of finely-divided zircon, silica, talc, graphite, mica or clay or mixtures of these refractories, applied in a gaseous suspension, e.g. in a bed fluidized by air or inert gas or in a spray. Melted particles of a resin, such as an epoxy resin, wood rosin or pitch, may first be sprayed on to the core &c. or it may be heated and dipped in a fluidized bed of resin particles. The hot core &c. may be dipped in a fluidized bed of resin-coated refractory particles, or one of resin particles, and then one of (different) refractory particles. The process may be repeated. The core &c. may be dipped in a fluidized bed of mixed resin and refractory particles. Opposite electric charges may be applied to the core &c. and the particles. Resincoated particles may comprise resin in an amount 2-100%, or more, by weight of the refractory.