FOUNDRY MIXES CONTAINING AN ORGANIC ACID SALT AND THEIR USES
Disclosed is a foundry mix containing an organic salt and its use to make foundry shapes by the warm-box, hot-box, no-bake, and cold-box process, the use of these foundry shapes to make metal castings, and the metal castings prepared by the process.
1 . A foundry mix comprising:
(a) foundry aggregate; and
(b) an organic salt in an amount effective to reduce the veining of a metal casting prepared with the foundry mix.
2 . The foundry mix of claim 1 which further comprises an iron oxide selected from the group consisting of red iron oxide, black iron oxide, and mixtures thereof.
3 . The foundry mix of claim 2 wherein the iron oxide is red iron oxide.
4 . The foundry mix of claim 3 wherein the foundry aggregate comprises silica sand.
5 . The foundry mix of claim 4 wherein the organic acid salt is selected from the group consisting of citrate salts, acetate salts, tartrate salts and mixtures thereof.
6 . The foundry mix of claim 5 wherein the salt is sodium citrate.
7 . The foundry mix of claim 4 or 5 wherein the weight ratio of an organic acid salt to red iron oxide is from 1:1 to 4:1.
8 . The foundry mix of claim 7 wherein the weight ratio of organic acid salt to red iron oxide is from 1:1 to 2:1.
9 . The foundry mix of claim 9 wherein the foundry mix contains an organic binder.
10 . The foundry mix of claim 9 wherein the binder is a phenolic urethane binder or an epoxy acrylate binder.
11 . The foundry mix of claim 10 wherein the foundry mix contains a catalyst.
12 . The foundry mix of claim 9 wherein the amount of organic acid salt in the foundry mix is from 0.5 percent by weight to 4.0 percent by weight based upon the weight of the foundry aggregate.
13 . The foundry mix of claim 11 wherein the amount of organic acid salt in the foundry mix is from 0.5 percent by weight to 4.0 percent by weight based upon the weight of the foundry aggregate.
14 . The foundry mix of claim 12 wherein the amount of organic acid salt in the foundry mix is from 0.5 percent by weight to 2.5 percent by weight based upon the weight of the foundry aggregate.
15 . The foundry mix of claim 13 wherein the amount of organic acid salt in the foundry mix is from 0.5 percent by weight to 2.5 percent by weight based upon the weight of the foundry aggregate.
16 . A cold-box process for preparing a foundry shape comprising:
(a) introducing the foundry mix of claim 9 into pattern to form a foundry shape;
(b) contacting the foundry shape of (A) with a vaporous curing catalyst capable of curing the shape;
(c) allowing said shape resulting from (B) to cure until said shape becomes handleable; and
(d) removing said shape from the pattern.
17 . A process for casting a metal part which comprises:
(a) inserting a foundry shape prepared by the process of claim 16 into a mold assembly;
(b) pouring metal, while in the liquid state, into said mold assembly;
(c) allowing said metal to cool and solidify; and
(d) then separating the cast metal part from the mold assembly.
18 . A metal part prepared in accordance with claim 17 .
19 . A no-bake process for preparing a foundry shape comprising:
(a) introducing a foundry mix of claim 11 into a pattern to form a foundry shape:
(b) allowing said shape of (A) to cure until said shape becomes handleable; and
(c) removing said shape from the pattern.
20 . A process for casting a metal part which comprises:
(a) inserting a foundry shape prepared by the process of claim 19 into a mold assembly;
(b) pouring metal, while in the liquid state, into said mold assembly;
(c) allowing said metal to cool and solidify; and
(d) then separating the cast metal part from the mold assembly
21 . A metal part prepared in accordance with claim 20 .
22 . A warm-box process for preparing a foundry shape comprising:
(a) introducing a foundry mix of claim 11 into a pattern to form a foundry shape:
(b) heating said shape to a temperature from 150° C. to 260° C.;
(c) allowing said shape of (A) to cure until said shape becomes handleable; and
(d) removing said shape from the pattern.
23 . A process for casting a metal part which comprises:
(a) inserting a foundry shape prepared by the process of claim 22 into a mold assembly;
(b) pouring metal, while in the liquid state, into said mold assembly;
(c) allowing said metal to cool and solidify; and
(d) then separating the cast metal part from the mold assembly
24 . A metal part prepared in accordance with claim 23 .