Characterization of Hot-Pressed Al2O3 with a Mo-Dispersed Phase.

Abstract

Compositions of alumina with a molybdenum-dispersed phase were investigated in the 0 to 5 volume percent Mo range. These compositions were also prepared with a 0.5 weight percent MgO addition. All specimens were fabricated by hot pressing and near theoretical densities were achieved. Specimens were characterized by metallographic and X-ray diffraction analyses, and the microhardness, elastic moduli, tensile strength, and fracture energy were determined. Results revealed that Mo additions did not affect grain growth while in contrast, MgO additions significantly inhibited grain growth. However, Mo additions did reduce the elastic moduli and microhardness, but did not measureably affect the tensile strength. A 50% increase in fracture energy was found in the Al2O3 + 5% Mo composition compared with Al2O3. In addition, specimens were successfully hot pressed with a microstructure graded from Al2O3 to the 5% Mo composition. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1970
Accession Number
AD0722239

Entities

People

  • D. R. Petrak
  • David T. Rankin
  • Jacob J. Stiglich Jr.
  • Robert Ruh

Organizations

  • United States Army Research Laboratory

Tags

DTIC Thesaurus Topics

  • Contrast
  • Diffraction
  • Diffraction Analysis
  • Grain Growth
  • Hot Pressing
  • Mechanical Properties
  • Mechanical Working
  • Microhardness
  • Microstructure
  • Molybdenum
  • Tensile Strength
  • X Rays
  • X-Ray Diffraction

Fields of Study

  • Materials science

Readers

  • Materials Science (Mechanical Engineering).
  • Materials Science and Engineering.
  • Surface Engineering/Surface Coating Technology.