Ultrahigh-Vacuum Creep Behavior of Columbium and Tantalum Alloys at 2000 degs and 2200 degs F for Times Greater Than 1000 Hours

Abstract

Creep tests of 1000 hours and greater were conducted at 2000 degrees and 2200 degrees F on six commercially available refractory alloys at pressures of 10 (exp -8) to 10 (exp -9) torr. The creep behavior of three columbium alloys, FS-85 (Cb + 28Ta + 10W + 1Zr), D-43, (Ch + 10W + 1Zr +0.1C), and Cb-752 (Cb +10W + 2.5Zr), and three tantalum alloys, T-222 (Ta + 9.6W + 2.4Hf + 0.01C), T-111 (Ta + 8W + 2Hf), and Ta-10W (90Ta + 10W) was determined stress-to-density ratios of 2.6x10(exp 4) and 1.3x10(exp 4) inches, respectively, at 2000 degrees and 2200 degrees F. Comparison of creep behavior on the density-compensated basis shows that the tantalum alloy T-222 was the most creep resistant material evaluated. A total creep strain of only 0.1 percent resulted from testing this alloy for 5000 hours. The relative order of creep resistance, on a density-compensated basis, was the same for the materials evaluated at 2000 degrees and 2200 degrees F; T-222, Ta-10W, D43, FS-85, T-111, and Cb-752.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1966
Accession Number
ADA454218

Entities

People

  • Robert H. Titran
  • Robert W. Hall

Organizations

  • National Aeronautics and Space Administration

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Alkali Metals
  • Alloys
  • Corrosion Resistance
  • Creep Strength
  • Creep Tests
  • Grain Size
  • Heat Energy
  • Heat Treatment
  • High Temperature
  • Materials
  • Measurement
  • Metals
  • Refractory Materials
  • Resistance
  • Tantalum Alloys
  • Temperature Gradients
  • Ultrahigh Vacuum

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Thermal Physics or Thermal Science.
  • Thin Film Deposition Science.