Effects of Thermal-Mechanical Processing on the Microyield Strength of Invar

Abstract

Microyield strengths (MYS) were determined for 20- and 40-mil Invar sheet, 0.5-in.-diam rod, and 0.5-in.-diam (1/32 wall thickness) tube using resistance strain gages. The various shapes were also characterized in terms of metallography and mechanical properties. Several heat treatments were studied for each shape. The MYS ranged from 9 to 31 ksi (62 to 214 MPa). Stretched sheet had the highest MYS. Slow furnace cooling increased the MYS of rod and tube. Stress versus plastic strain curves were characterized by the logarithmic relationship sigma = K Epsilon (N)(P). Two sets of K and n (below and above the MYS) were determined for sheet with 2% stretching.

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Document Details

Document Type
Technical Report
Publication Date
Aug 12, 1976
Accession Number
ADA029980

Entities

People

  • C. S. Susskind
  • D. L. Dull
  • E. G. Wolff

Organizations

  • The Aerospace Corporation

Tags

Communities of Interest

  • Air Platforms
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Chemical Composition
  • Coefficients
  • Cold Working
  • Corporations
  • Heat Treatment
  • Materials
  • Materials Science
  • Mechanical Properties
  • Mechanical Working
  • Metal Matrix Composites
  • Residual Stress
  • Statistical Analysis
  • Strain Gages
  • Tensile Strength
  • Thermal Expansion
  • Yield Strength

Fields of Study

  • Materials science

Readers

  • Cellular and Molecular Pathways of Apoptosis.
  • Materials Science (Mechanical Engineering).
  • Materials Science and Engineering.