Claims
- 1. A method of heat treating fabricated metal parts comprising the steps of:
- (A) heating the parts to a temperature above a metallurgical transformation range;
- (B) placing the parts in a heated, agitated quench bath comprising an aqueous solution of about .[.10%.]. .Iadd.1.75% .Iaddend.to 25% by volume of polyvinylpyrrolidone having a molecular weight in the range of between .[.900,000 and 3,000,000.]. .Iadd.1,270,000 and 2,240,000.Iaddend.;
- (C) removing the parts from the quench bath; and
- (D) water washing the parts to substantially remove any polymeric film formed on the parts in the quench bath.
- 2. A method as defined in claim 1 wherein the concentration of the polyvinylpyrrolidone is approximately .[.25% by volume.]. .Iadd.5% by weight.Iaddend.. .[.3. A method as defined in claim 1 wherein the polyvinylpyrrolidone has a molecular weight in the range of between about
- 1,270,000 and 2,240,000..]. 4. A method as defined in claim 1 further including the step of recovering the polyvinylpyrrolidone from the wash
- water. 5. A method as defined in claim 1 wherein the washing step is performed by a power spray at a pressure in the range of about 20 to 45
- psi. 6. A method as defined in claim 1, wherein the bath temperature is
- about 130.degree. F. 7. A method of heat treating fabricated metal parts comprising the steps of:
- (A) heating the parts to a temperature above a metallurgical transformation temperature range;
- (B) placing the parts in a heated, agitated quench bath consisting essentially, by weight, of:
- (i) about .[.7%.]. .Iadd.1.75% to 5% .Iaddend.of polyvinylpyrrolidone having a molecular weight in the range of between .[.900,000 and 3,000,000.]. .Iadd.1,270,000 and 2,240,000.Iaddend.;
- (ii) about 7% of an amine-neutralized, carboxylic acid;
- (iii) about 7% of triethanolamine; and
- (iv) the balance water;
- (C) removing the parts from the quench bath; and
- (D) water washing the parts to substantially remove any polymeric film
- formed on the parts in the quench bath. .[.8. A method as defined in claim 7 wherein the polyvinylpyrrolidone has a molecular weight in the
- range of between about 1,270,000 and 2,240,000..]. 9. A method as defined in claim 7 further including the step of recovering the polyvinylpyrrolidone, amine neutralized carboxylic acid and
- triethanolamine from the wash water. 10. A method of heating treating fabricated metal parts comprising the steps of:
- (A) heating the parts to a temperature above a metallurgical transformation temperature range;
- (B) placing the parts in a heated, agitated quench bath consisting essentially, by weight .[.,.]. of:
- (i) about .[.20%.]. .Iadd.1.75% to 5% .Iaddend.of polyvinylpyrrolidone having a molecular weight in the range between .[.900,000 and 3,000,000.]. .Iadd.1,270,000 and 2,240,000.Iaddend.;
- (ii) about 0.8% borax;
- (iii) about 0.2% sodium nitrite; and
- (iv) the balance water;
- (C) removing the parts from the quench bath; and
- (D) water washing the parts to substantially remove any polymeric film
- formed on the parts in the quench bath. 11. A method as defined in claim 10 wherein said quench bath also includes about 0.5%, by weight, of a bacteriocidal agent. .[.12. A method as defined in claim 10 wherein the polyvinylpyrrolidone has a molecular weight in the range of between about
- 1,270,000 and 2,240,000..]. 13. A method as defined in claim 10 further including the step of recovering the polyvinylpyrrolidone, borax and
- sodium nitrite from the wash water. 14. A method for controlling the microstructure of carbon steel objects by immersing said objects, after preheating in a water based polymeric bath wherein the improvement comprises constituting said bath as an aqueous solution comprising about .[.7-20%.]. .Iadd.1.75% to 5% .Iaddend.by weight polyvinylpyrrolidone having a molecular weight between about .[.900,000 and 3,000,000.].
- .Iadd.1,270,000 and 2,240,000 .Iaddend.and the balance water. 15. The method of claim 14 wherein the quenchant is constituted of said polyvinylpyrrolidone and water and, in addition, at least about 7% weight of each triethanolamine and an amine neutralized, carboxylic acid rust
- inhibitor. 16. The method of claim 15 including the later step of water washing the objects using a power spray at a pressure in the range of about 20 to 40 psi to remove residual polyvinylpyrrolidone from the objects.
RELATED APPLICATION
This application is a continuation-in-part of Ser. No. 819,204 filed Jan. 15, 1986 now abandoned which is a continuation-in-part of Ser. No. 766,598 filed Aug. 19, 1985, now abandoned.
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Continuation in Parts (2)
|
Number |
Date |
Country |
Parent |
819204 |
Jan 1986 |
|
Parent |
766598 |
Aug 1985 |
|
Reissues (1)
|
Number |
Date |
Country |
Parent |
915427 |
Oct 1986 |
|