Inorganic foundry binder systems and their uses
AssigneeAshland Inc.
InventorsRuth A. Bambauer, Heimo J. Langer, Steven C. Akey
Life of this patent
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Abstract
This invention relates to inorganic no-bake foundry binder systems and their uses. The binder systems comprise as separate components: (A) mono-aluminum phosphate in an aqueous solution containing specified phosphoric acids, and (B) magnesium oxide; and certain specified zinc compounds in either the Component A, Component B or both. The components of the binder system react when they are mixed with a foundry aggregate to prepare foundry mixes which are used to prepare foundry molds and cores. The foundry molds and cores are used to cast metals.
Claims7
A no-bake process for preparing a foundry mold or core comprising:
- (1) mixing at about ambient temperature a foundry aggregate with an effective bonding amount of up to about 10% by weight, based upon the weight of the aggregate, of a binder composition comprising as separate components:
- A. an acid phosphate in an aqueous acid solution of a phosphoric add selected from the group consisting of orthophosphoric add, pyrophosphoric acid, trimetaphosphoric acid, tetrametaphosphoric acid, polyphosphoric acid, and mixtures thereof, and
- B. magnesium oxide;
- and
- wherein a zinc compound in is added to either component A, component B, or both, and components A and B are added sequentially to the aggregate without regard to the order of addition;
- (2) introducing the foundry mix obtained from step (1) into a pattern;
- (3) allowing the foundry mix to harden in the pattern until it becomes self supporting;
- and
- (4) thereafter removing the shaped foundry mix of step from the pattern and allowing it to further cure, thereby obtaining a hard, solid, cured mold.
Dependencies are inferred from the claim text.