Fatigue Mechanisms in Metallic Matrix Composites.

Abstract

Fatigue crack growth in alumina particulate reinforced Ni3Al alloy composites, IC-50/Al2O3, fabricated using a spray deposition and co-injection process was examined and compared with that in a conventional nickel-based superalloy, Inconel 718. Single edge-notched fatigue crack growth specimens were tested under constant dK conditions using a custom fully automated servo-hydraulic test system. The results indicate that the threshold value of dK is at least as high as that for monolithic IC-5O, regardless of whether the composite is in the as-sprayed or HIPed condition. However, the HIPed microstructure exhibits a higher fatigue crack growth resistance in the Paris law regime compared to the as-sprayed material. Both composites exhibit a lower crack growth resistance compared to that for unreinforced IC-5O. Compared with Inconel 718, the present IC-5O MMCs consistently exhibit substantially better fatigue crack growth resistance properties.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1996
Accession Number
ADA319912

Entities

People

  • Enrique J. Lavernia
  • James C. Earthman

Organizations

  • University of California, Irvine

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Advanced Materials
  • Air Force
  • Alloys
  • Biochemical Engineering
  • Composite Materials
  • Fatigue Life
  • Materials
  • Materials Science
  • Mechanical Properties
  • Mechanics
  • Microstructure
  • Modulus Of Elasticity
  • Oxidation Resistance
  • Resistance
  • Scientific Research
  • Superalloys
  • Transitions

Fields of Study

  • Materials science

Readers

  • Materials Science (Mechanical Engineering).
  • Powder metallurgy of Titanium alloys.
  • Reinforced Composite Materials