Strain Energy Criterion of Martensitic Transformation.

Abstract

A new theory of martensitic transformation based on the minimization of total strain energy has been developed, where the plastic relaxation strain (PRS) concept is introduced in order to relieve the high internal stress due to martensitic transformation in Ti, Ti-Mn, -Cr, -Ta, and -Zr alloys. For the analysis of Ti martensite, a total of 84 glide and twin systems were evaluated as PRS. For oblate spheroids with aspect ratio less than 0.01, (1,0,-1,1) <-1,0,1,2> twin, (1,0,-1,1) <-1,-1,2,3> glide and (1,1,-2,2) <-1,-1,2,3> glide or twin systems produced strain energy minima at shear strain less than 2%, although crystal plasticity data of Paton and Backofen rules out the latter twin system. Theoretical predictions on habit plane in Ti, Ti-Ta and -Zr alloys turned out to be close to (334) sub B. In Ti-Mn and -Cr alloys, both (334) sub B and (344) sub B habit planes were predicted depending on the variant of (1,0,-1,1) <-1,0,1,2> twin. These and other predictions are in excellent agreement with experimental observations.

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1976
Accession Number
ADA023781

Entities

People

  • Kanji Ono
  • M. Shibata

Organizations

  • University of California, Los Angeles

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Agreements
  • Alloys
  • Aspect Ratio
  • Martensite
  • Observation
  • Plastic Properties

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Materials Science (Mechanical Engineering).
  • Powder metallurgy of Titanium alloys.