Creep-rupture behavior of candidate stirling engine cast iron-base superalloys
- NASA Lewis Research Center, Cleveland, OH (USA)
The Stirling engine is under investigation jointly by the DOE and NASA as an alternate to the automotive internal combustion engine. Present design criteria require cast cylinder heads and regenerator housings to operate 3500 hours from ambient to 775 C while pressurized to 15 MPa with hydrogen. Creep-rupture tests in air and 15 MPa hydrogen were performed on candidate iron-base alloys XF-818, CRM-6D, and SA-F11 at 760, 815, and 870 C in the as cast condition and with a simulated vacuum braze cycle. The time to 1% strain, minimum creep rate and rupture life as a function of stress was statistically analyzed for each temperature. Multiple linear regression analysis of a temperature-compensated Sherby-Dorn type relationship yielded apparent activation energies and stress exponents. The 15 MPa hydrogen test environment did not significantly reduce the 3500 hour rupture life. The creep-rupture properties are compared to current design criteria for the automotive Stirling engine.
- OSTI ID:
- 5250408
- Report Number(s):
- CONF-840909--
- Journal Information:
- TMS (The Metallurgical Society) Paper Selection; (USA), Journal Name: TMS (The Metallurgical Society) Paper Selection; (USA) Vol. 56; ISSN 0197-1689; ISSN TMPSA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Creep-rupture behavior of candidate Stirling engine alloys after long-term aging at 760/sup 0/C in low-pressure hydrogen
Creep-rupture behavior of iron superalloys in high-pressure hydrogen
Related Subjects
330201 -- External Combustion Engines-- Stirling Cycle
36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ACTIVATION ENERGY
AIR
ALLOYS
CARBIDES
CARBON COMPOUNDS
CAST IRON
CREEP
DESIGN
ELEMENTS
ENERGY
ENGINES
FAILURES
FLUIDS
GASES
HEAT ENGINES
HYDROGEN
IRON ALLOYS
IRON BASE ALLOYS
IRON CARBIDES
IRON COMPOUNDS
MATERIALS TESTING
MATHEMATICS
MECHANICAL PROPERTIES
MECHANICAL TESTS
NONMETALS
PRESSURIZING
REGRESSION ANALYSIS
RUPTURES
SERVICE LIFE
STATISTICS
STIRLING ENGINES
STRAINS
STRESS ANALYSIS
TEMPERATURE DEPENDENCE
TESTING
TRANSITION ELEMENT COMPOUNDS