Modified 9Cr-1Mo steel shows excellent potential for steam generator applications
A 9Cr-1Mo steel with properties improved over other ferritics in the ranges from 9 to 12% Cr and 1 to 2% Mo and over the widely used 2 1/2 Cr-1Mo steel has recently been developed. The main changes in the modified alloy, compared with the standard alloy, include: addition of niobium and vanadium, to improve the alloy's elevated-temperature strength properties; a specified range for each element; and a specification for nitrogen, which is not listed for the standard 9Cr-1Mo. Microstructural work has indicated that the improved strength of the modified alloy comes from two factors: (1) fine M/sub 23/C/sub 6/ precipitate particles nucleate on Nb/C, N, which comes out first during the heat treatment; and (2) the vanadium enters M/sub 23/C/sub 6/ and retards its growth at the service temperature. Mechanical properties discussed were Charpy-impact, tensile, and creep properties. Other properties included were: thermal expansion coefficient, fatigue tests, steam and air oxidation, and welding. 3 figures, 2 tables. (DP)
- Research Organization:
- Oak Ridge National Lab., TN
- OSTI ID:
- 6204219
- Journal Information:
- Mater. Compon. Fossil Energy Appl.; (United States), Vol. 41
- Country of Publication:
- United States
- Language:
- English
Similar Records
Modified 9Cr-1Mo steel for advanced steam generator applications
Microstructure characterization of heat affected zone after welding in Mod.9Cr–1Mo steel
Related Subjects
CHROMIUM-MOLYBDENUM STEELS
CREEP
FATIGUE
IMPACT STRENGTH
TENSILE PROPERTIES
THERMAL EXPANSION
STEAM GENERATORS
MATERIALS
USES
WELDING
ALLOYS
BOILERS
CHROMIUM ALLOYS
CHROMIUM STEELS
EXPANSION
FABRICATION
IRON ALLOYS
IRON BASE ALLOYS
JOINING
MECHANICAL PROPERTIES
STEELS
VAPOR GENERATORS
360103* - Metals & Alloys- Mechanical Properties
360104 - Metals & Alloys- Physical Properties
360101 - Metals & Alloys- Preparation & Fabrication