Strengthening of NiAl Matrix Composites.

Abstract

The significant result is that the observed strengthening due to various types reinforcements (Al203 and TiB2) with same size is almost identical. The smaller size reinforcement 5 micrometers vs 150 micrometers produces greater strengthening. Also, the strengthening due to Al2O3 whiskers, which have long l/d (length to diameter) ratios of 10 to 100 is no greater than particulate Al203 and TiB2 of approximately the same size, which is a further indication that a load transfer mechanism is not applicable for these composites. A detailed examination of the data still suggests that the thermally-activated-rate controlling mechanism is the stress assisted motion of jogged screw dislocations. The specific details of the process are now be worked out to be able to obtain the proper stress and temperature dependence of the activation parameters. The strengthening observed in the composites at both high and low temperatures is due to an increase in the internal stress. This internal stress is independent of test temperature and stress,

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Document Details

Document Type
Technical Report
Publication Date
Nov 30, 1994
Accession Number
ADA288923

Entities

People

  • R. J. Arsenault

Organizations

  • University of Maryland

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Chemical Analysis
  • Composite Materials
  • Crystal Structure
  • Crystallography
  • Electron Microscopes
  • Failure Mode And Effect Analysis
  • Finite Element Analysis
  • Materials
  • Materials Engineering
  • Materials Laboratories
  • Materials Science
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Modulus Of Elasticity
  • Physics Laboratories
  • Stress Strain Relations

Readers

  • Materials Science and Engineering.
  • Powder metallurgy of Titanium alloys.