Carburization of metal articles
AssigneeKeystone Investment Corporation
InventorsPeter G. Imbrogno, John C. Kosco
Life of this patent
Estimating the term…
Abstract
The present invention relates to a process for carburizing a metal article comprising: (1) heating the metal article to an elevated temperature, (2) coating the heated metal article with a graphite suspension to produce a graphite coated metal article, wherein the graphite suspension is comprised of graphite and an organic or inorganic liquid having a boiling point of at least 50° F. (28° C.) less than the elevated temperature to which the metal article is heated, (3) heat treating the graphite coated metal article under a non-oxidizing environment at a temperature which is sufficient to promote the diffusion of carbon into the metal structure of the article to produce a carburized metal article, and (4) cooling the carburized metal article to ambient temperature.
Claims20
A process for carburizing a metal article comprising:
- (1) heating the metal article to an elevated temperature, wherein the metal article is a green powder metal article, (2) coating the heated metal article with a graphite suspension to produce a graphite coated metal article, wherein the graphite suspension is comprised of graphite and an organic or inorganic liquid having a boiling point of at least 50° F. less than the elevated temperature to which the metal article is heated, (3) heat treating the graphite coated metal article under a non-oxidizing environment at a temperature which is sufficient to promote the diffusion of carbon into the metal structure of the article to produce a carburized metal article, and wherein the temperature is sufficient to sinter the powder metal article, and (4) cooling the carburized metal article to ambient temperature;
- wherein the metal article is heated in step (1) to a temperature which is 50° F. to 200° F. higher than the boiling point of the organic or inorganic liquid.
A process for carburizing a metal article comprising:
- (1) heating the metal article to an elevated temperature, (2) coating the heated metal article with a graphite suspension to produce a graphite coated metal article, wherein the graphite suspension consists of graphite and at least one organic or inorganic liquid having a boiling point of at least 50° F. less than the elevated temperature to which the metal article is heated, (3) heat treating the graphite coated metal article under a non-oxidizing environment at a temperature which is sufficient to promote the diffusion of carbon into the metal structure of the article to produce a carburized metal article, and (4) cooling the carburized metal article to ambient temperature;
- wherein the metal article is heated in step (1) to a temperature which is 50° F. to 200° F. higher than the boiling point of the organic or inorganic liquid.
Dependencies are inferred from the claim text.