Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

High-temperature creep behavior of second-phase particle-strengthened tungsten-rhenium alloys

Thesis/Dissertation ·
OSTI ID:5408941

The creep behavior of W{sup {minus}4}Re{sup {minus}0}.26HfC, W{sup {minus}3}.6Re{sup {minus}1}ThO{sub 2}, W{sup {minus}11}Re{sup {minus}1}ThO{sub 2}, and W{sup {minus}26}Re{sup {minus}1}ThO{sub 2} alloys were evaluated at elevated temperatures (between 1955 and 2500 K) in a custom-built high vacuum creep testing facility. These alloys are promising emitter materials for the Thermionic Energy Converter. The effects of stress and temperature on the creep rate of these alloys were determined and the stress exponents and creep activation energies of these alloys were measured. Results showed that HfC particles have a very high strengthening effect on the W{sup {minus}4}Re matrix up to 2200 K. At temperatures higher than 2200 K the coarsening rate of HfC is so high that they lose their strengthening effect rapidly. Comparing the creep strength of the arc-melted W{sup {minus}4}Re{sup {minus}0}.26HfC with that of the P/M W-Re{sup {minus}1}ThO{sub 2} alloys, it was found that at temperatures less than or equal to 2200 K, W{sup {minus}4}Re{sup {minus}0}.26HfC has the highest creep.

Research Organization:
Arizona State Univ., Tempe, AZ (United States)
OSTI ID:
5408941
Country of Publication:
United States
Language:
English