Accession Number:

AD0694511

Title:

THE CARBURIZATION OF FOUR AUSTENITIC STAINLESS STEELS.

Descriptive Note:

Rept. for Jun-Dec 68,

Corporate Author:

AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Personal Author(s):

Report Date:

1969-09-15

Pagination or Media Count:

40.0

Abstract:

Four austenitic stainless steels AISI Types 304 18Cr-8Ni, 316 18Cr-8Ni Mo, 321 18Cr-8Ni Ti, and 347 18Cr-8Ni Cb were carburized in a mixture of methane-hydrogen 1-12 vol methane up to 25 hr in a temperature range of 730C 1350F to 1040C 1900F. Carburization occurrence diagrams, i.e., time and temperature at which carburization is observed, for each of the steels are given. Typical carburized structures at 100x and 500x are given. For this work, the carburized layer was considered to comprise both zones. Photographs at 500x show the complexity of the carbide-austenite zone. The carbide formed in all cases was Cr7C3. The rate of carburization, case depth versus time, is given for each of the steels at temperatures from 870C 1600F to 1040C 1900F. The general form of the curves is parabolic. The carburization rate for titanium-bearing Type 321 is slightly different from that of the other materials. Microhardness Knoop traverses were made on several of the steels, and hardness gradients for each of the steels were established. Author

Subject Categories:

  • Properties of Metals and Alloys
  • Rocket Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE