Creep of Tantalum T-222 Alloy in Ultrahigh Vacuum for Times Up to 10 000 Hours
Abstract
The long-time creep behavior of fine-grained (0. 016-mm) Ta-9.11W-1. 91Hf-0. was determined over the temperature range of 2000 degrees to 2600 degrees F (1093 degrees to 1426 degrees in a vacuum of 10(exp -8) torr (1.33x10(exp -6 N/m squared). Creep stresses ranged fro 2500 to 20,000 psi (17.5x10(exp 6) to 138x10(exp 6) N/m squared) for test times up to 10,000 hours. At temperatures ranging from 2000 degrees to 2600 degrees F (1093 degrees to 1426 degrees C), stress levels to limit creep to 1 percent in 10,000 hours are 28,000 and 800 psi (193x10(exp 6) and 6x10(exp 6) N/m squared), respectively. The stress dependence of the steady creep rate was 3, and the temperature dependence of steady creep was equivalent to an apparent activation energy of 150 kcal/g-mole (627 450 J/g-mole).
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1968
- Accession Number
- ADA452636
Entities
People
- Robert H. Titran
Organizations
- National Aeronautics and Space Administration