Accession Number:

ADA463681

Title:

Modeling Plasticity of Ni3Al-Based L12 Intermetallic Single Crystals-I. Anomalous Temperature Dependence of the Flow Behavior (Preprint)

Descriptive Note:

Journal article

Corporate Author:

UES INC DAYTON OH

Report Date:

2006-07-01

Pagination or Media Count:

55.0

Abstract:

A comprehensive mechanism-based crystallographic constitutive model has been developed for L 12-structured Ni3Al-based intermetallic single crystals. This model represents the unusual thermo-mechanical behaviors of Ni3Al, such as the anomalous temperature dependence of both the flow stress and strain-hardening rate SHR, the strain dependence of these anomalous behaviors, and an orientation-dependent tension-compression asymmetry. The model framework was based on two major contributions to plastic flow, namely the repeated cross-slip exhaustion and athermal defeat of screw-character dislocations, and the motion of the macro-kinks MKs. The contribution of irreversible obstacle storage was incorporated into the constitutive formulations as a resistance against the glide of MKs. The model was implemented in a finite element method numerical framework, and the simulation results showed qualitative agreement with experimental observations.

Subject Categories:

  • Inorganic Chemistry
  • Operations Research
  • Crystallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE