Modified 9Cr-1Mo steel for advanced steam generator applications

Conference · Mon Jan 01 04:00:00 EST 1990

OSTI ID:6670028

Brinkman, C R; Alexander, D J; Maziasz, P J

Results are reported from several types of mechanical property tests conducted on a number of commercial heats of modified 9Cr-1Mo steel. Data from long term creep-rupture tests conducted on base and weldment material were compared with an analytical model which has been shown to give good agreement between measured and predicted values. Weldment material had somewhat inferior creep-rupture strength in comparison to base material due to a soft zone at the edge of the HAZ. Data are presented from elevated temperature tensile and creep-rupture tests conducted n material thermally aged for periods of up to 75,000 h (8.6 years). Some reduction in strength was shown to occur in comparison to unaged material. Models were developed for predicting the reduction in short term elevated temperature tensile and yield strength for material thermally aged in the temperature range of 482 to 704{degree}C. Results from Charpy impact tests conducted on material thermally aged at 538{degree}C for periods of up to 75,000 h showed an increase in the ductile-brittle transition temperature. Finally, results from transmission electron microscopy studies were presented to explain changes in mechanical properties due to thermal aging. These observations showed that Laves phase precipitation and recovery occurs on prolonged exposure of this alloy in this temperature range. 9 refs.

• Research Organization: Oak Ridge National Lab., TN (USA)
• Sponsoring Organization: DOE/NE
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6670028
• Report Number(s): CONF-901026-1; ON: DE90010497
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
200104 -- Fossil-Fueled Power Plants-- Components
36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
360103* -- Metals & Alloys-- Mechanical Properties
BOILERS
CHARPY TEST
CHEMICAL COMPOSITION
CHROMIUM-MOLYBDENUM STEELS
CREEP
CRYSTAL STRUCTURE
DESTRUCTIVE TESTING
DUCTILITY
HARDNESS
HEAT AFFECTED ZONE
HEAT TREATMENTS
IMPACT TESTS
JOINTS
MATERIALS TESTING
MECHANICAL PROPERTIES
MECHANICAL TESTS
MICROSTRUCTURE
STEAM GENERATORS
TENSILE PROPERTIES
TESTING
VAPOR GENERATORS
WELDED JOINTS
ZONES