Thermal Sprayed Nanostructured Hard Coatings

Abstract

Hardcoatings of WC/12Co and Al2O3/13TiO2, produced by High Velocity Oxy-Fuel (HVOF) and High Energy Plasma (HEP) spraying, have been investigated. In HVOF spraying, nanostructured WC/Co coatings experience more extensive decarburization than conventional coatings, whereas in HEP spraying, just the opposite effect occurs. This is explained in terms of the influence of temperature on the decarburization mechanism. In the Al2O3/13TiO2 case, HEP spraying generates a metastable coating, due to rapid quenching of the plasma melted particles on the substrate. The metastable phase has a defect spinel structure and a nanocrystalline grain size. When heated, it decomposes into an equilibrium two-phase structure, consisting of alpha-Al2O3 and beta-Al2O3-TiO2. Both nanostructured cermets and ceramics have potential as wear-resistant coatings.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2000
Accession Number
ADP011809

Entities

People

  • B. H. Kear
  • W. E. Mayo

Organizations

  • Rutgers University–New Brunswick

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Crystal Structure
  • Heat Energy
  • Heat Treatment
  • Liquid Phases
  • Materials
  • Materials Processing
  • Nanocomposites
  • Nanoparticles
  • Particle Size
  • Particles
  • Phase Diagrams
  • Phase Transformations
  • Plasma Spraying
  • Production Engineering
  • Thermal Spraying
  • X Rays
  • X-Ray Diffraction

Fields of Study

  • Materials science

Readers

  • Plasma Physics / Magnetohydrodynamics
  • Powder metallurgy of Titanium alloys.
  • Surface Engineering/Surface Coating Technology.

Technology Areas

  • Microelectronics