New Techniques in Measuring Plastic Strain in a Memory Material

Abstract

A Nickel-Titanium memory material was studied for the purpose of characterizing its stress-strain behavior, energy absorption capacity, and cyclic response. Instrumentation problems encountered in the testing of this unique material are discussed from the standpoint of thermal recovery effects on strain readings from strain gages and LVDT-type extensometers. Nickel foil type temperature sensors were used to measure surface temperatures from heat generated in the course of plastically straining the material. In addition, the sensors also monitored the heat applied to the specimen to effect thermal recovery from the plastic strain. Temperature-time curves using a strip chart recorder exhibited possible phase changes occurring in the material during thermal recovery after the half cycle of straining.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1973
Accession Number
AD0768497

Entities

People

  • R. V. Milligan

Tags

Communities of Interest

  • Sensors
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Adhesives
  • Alloys
  • Cells
  • Determinants (Mathematics)
  • Dissipation
  • Extensometers
  • Gages
  • Heat Treatment
  • Heating
  • Instrumentation
  • Load Cells
  • Materials
  • Measurement
  • Ordnance Laboratories
  • Recording Systems
  • Strain Gages
  • Surface Temperature

Readers

  • Mechanical Engineering/Mechanics of Materials.
  • Thermal Physics or Thermal Science.