MECHANICAL PROPERTIES OF AGE-HARDENED FE-20NI MARTENSITES.
Abstract
Because of an interest in maraging steels for a submarine-hull weldment with a yield strength in the range 180,000 to 210,000 psi (HY-180/210), previous studies to establish the mechanism of age hardening in maraging steels have been extended to include a study of the mechanical properties of these steels. A series of Fe-20Ni maraging steels with single additions of titanium, aluminum, copper, and molybdenum are evaluated to determine the effect of different types of age-hardening reactions and the effect of retained austenite and cobalt additions on the yield-strength--impact-energy relation of these steels. The results indicated that single additions of titanium, aluminum, molybdenum, or copper significantly increased the yield strength of maraging steels when the as-quenched steels were aged, the relative effectiveness of the elements decreasing in the order in which they are mentioned. In the aged condition, an increase in the yield strength was accompanied by a decrease in the notch toughness of the maraging steels. This relation was exhibited by all the maraging steels regardless of the type of age-hardening mechanism-precipitation of Ni3Ti, Cu, or Ni3Mo, or an Al-Ni ordering reaction. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 30, 1963
- Accession Number
- AD0459675
Entities
People
- A. J. Birkle
- G. R. Speich
- Lew F. Porter
Organizations
- U.S. Steel