Back to results
US 5,211,768 AGranted
Method of nitriding work pieces of steel under pressure
AssigneeDegussa AG
InventorsFriedrich Preisser, Rudolf Seif
Life of this patent
Estimating the term…
Abstract
Very low-pore, thick nitride cases may be obtained in a short time during a gas nitriding process in accordance with the invention. This process includes nitriding in a gaseous mixture containing about 5 to 95% by volume ammonia and about 95 to 5% by volume nitrogen. The nitriding process is most preferably carried out at essentially a constant pressure above about 0.2 MPa.
Claims25
A method for nitriding steel work pieces, comprising:
- nitriding said work pieces by subjecting the work pieces to a temperature above 425.degree. C. and an essentially constant pressure above 0.2 MPa and for a sufficient period of time in a gaseous atmosphere which includes about 5 to 95% by volume ammonia and about 95 to 5% by volume molecular nitrogen, said pressure being sufficient to thereby provide the desired nitride case.
Dependencies are inferred from the claim text.