Accession Number:

AD0423805

Title:

AN ELECTRON-METALLOGRAPHIC STUDY OF EMBRITTLEMENT IN AN 18NI-8CO-MO MARAGING STEEL.

Descriptive Note:

Progress rept.,

Corporate Author:

UNITED STATES STEEL CORP PITTSBURGH PA

Personal Author(s):

• Birkle ,A. J.
• Dabkowski ,D. S.
• Porter ,L. F.
• Speich,G. R.

Report Date:

1963-09-27

Pagination or Media Count:

20.0

Abstract:

Recent information has indicated that 18Ni-8Co-Mo type maraging steels can be embrittled by holding at 1400 F during the solution annealing treatment. Thus, heavy maraging-steel plates 2 in. thick and over may be embrittled during solution annealing because they would cool slowly at temperatures in the vicinity of 1400 F. Because steel plates up to 4 in. thick are required for submarine-hull weldments, this embrittling tendency might severely limit the use of maraging steels in this application. Therefore, a metallographic study was initiated to determine the cause of the embrittlement in specimens of a 250ksi maraging steel submitted by INCO. Lightmicroscopy, electron-microscopy, X-ray-diffraction, electron-diffraction, and microprobe techniques were used in the investigation. Author

Descriptors:

• STEEL
• MARTENSITE
• SUBMARINE HULLS
• MICROSCOPY
• X RAY DIFFRACTION
• CARBIDES
• NITRIDES
• COBALT ALLOYS

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE