Creep of Nextel 720/Alumina Ceramic Matrix Composite with Diamond-Drilled Effusion Holes at 1200 deg C in Air and in Steam

Abstract

This effort evaluated the tensile creep behavior of Nextel720/alumina with diamond-drilled (DD) effusion holes at 1200C. Tensile properties at 1200C in laboratory air were unaffected by the presence of an array of 17 DD holes. Notably, examination of the composite microstructure did not reveal any damage caused by the drilling process. The DD specimens exhibited similar degradation to creep lifetimes as laser-drilled (LD) specimens for creep tests between 46-150 MPa in air, but contrary to unnotched and LD specimens, saw minimal degradation due to steam. These results were attributed to a change in dominant damage mechanism that caused minimum creep rates in air to exceed those in steam.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Mar 21, 2019
Accession Number
AD1076360

Entities

People

  • Megan L Harkins

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Ceramic Matrix Composites
  • Composite Materials
  • Creep
  • Creep Tests
  • Failure Mode And Effect Analysis
  • Materials
  • Materials Laboratories
  • Materials Processing
  • Materials Science
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Microscopy
  • Modulus Of Elasticity
  • Notch Sensitivity
  • Physical Properties
  • Technical Ceramics
  • Tensile Properties
  • Tensile Strength
  • X-Ray Computed Tomography

Fields of Study

  • Materials science

Readers

  • Geotechnical Engineering.
  • Materials Science and Engineering.
  • Reinforced Composite Materials

Technology Areas

  • Directed Energy