The mechanical and microstructural stability of austenitic stainless steels strengthened by MC-forming elements

Conference · Wed Jan 01 00:00:00 EST 1992

OSTI ID:5846369

Swindeman, R W; Maziasz, P J

Creep-resistant austenitic stainless steels have been developed that owe their strengths to the addition of MC-forming techniques. Examples are Esshete 1250, 17-14CuMo, Sumitomo ST3Cu{reg sign}, Nippon Kokan Tempaloy Al{reg sign}, and the HT-UPS steels designed by Maziasz. The HT-UPS steels, basically 14%Cr-16%Ni-2%Mo-Fe with V, Ti, and Nb additions, were found to have higher creep strengths than the other steels due to the formation of an ultrafine precipitate distribution on dislocations produced by warm or cold work prior to service. Under constant-load creep conditions, the microstructure of the HT-UPS steel was found to be stable for long periods of time, and creep rates changed very little over thousands of hours. Studies were made to determine if the strength of the HT-UPS alloys would be degraded by variable temperatures and stresses that could disturb the precipitate-stabilized dislocation microstructure. Experiments included variable stress creep testing, repetitious and combined creep-relaxation testing, and creep-fatigue testing. Temperatures were in the range 600 to 800{degrees}C. Times extended to beyond 20,000 h in some cases. Recovery creep strains were measured and used as an indicator of microstructural changes during creep. 8 figs.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5846369
• Report Number(s): CONF-920505-3; ON: DE91015314
• Resource Relation: Conference: International conference on creep of materials, Orlando, FL (United States), 17-21 May 1992
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
20 FOSSIL-FUELED POWER PLANTS
AUSTENITIC STEELS
CREEP
FOSSIL FUELS
RECRYSTALLIZATION
STRESS RELAXATION
ALLOYS
ENERGY SOURCES
FUELS
IRON ALLOYS
IRON BASE ALLOYS
MECHANICAL PROPERTIES
RELAXATION
STEELS
360103* - Metals & Alloys- Mechanical Properties
200104 - Fossil-Fueled Power Plants- Components