Grain Boundary Curvature in a Model Ni-Based Superalloy (Preprint)

Abstract

The local grain boundary curvature in a model Ni-based superalloy was measured experimentally using Dehoff's tangent count method. The results show that, in materials containing significant amounts of second-phase particles, the curvature parameter kappa, which relates the mean local curvature to the grain size, can adopt far lower values than have been reported previously. It is also shown that the value of kappa, is not a constant, as is usually assumed, but instead varies both with the volume fraction of second-phase particles and with the holding time during high-temperature annealing. The lowest values for kappa, were obtained for high particle volume fractions and long annealing times. Since the local boundary curvature constitutes the driving force for grain growth, these observations could help to explain grain growth phenomena in heavily pinned systems.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 2006
Accession Number
ADA463754

Entities

People

  • Kai Song
  • Mark Aindow

Organizations

  • University of Connecticut

Tags

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Alloys
  • Annealing
  • Boundaries
  • Chemical Compounds
  • Crystal Structure
  • Curvature
  • Grain Boundaries
  • Grain Growth
  • Grain Size
  • Heat Treatment
  • Materials
  • Materials Engineering
  • Materials Science
  • Particles
  • Powder Metallurgy

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Structural Health Monitoring of Composite Structures.
  • Thin Film Deposition Science.