CHEMICAL STRENGTHENING OF CERAMIC MATERIALS.

Abstract

An investigation of the effect of compressive surface layers on the strength of polycrystalline ceramic bodies is described. Low expansion surface layers were formed on conventional ceramics by chemical reactions at high temperatures. Failure, by shearing of the surface layers, was prevented by establishing gradual variations in composition within the body. Chemical strengthening was attempted with alumina, titania, spinel, magnesia, forsterite, steatite, nickel oxide, silica and cordierite bodies and was achieved with several of these materials. Glazing and quenching also resulted in improved flexural strength. Combined processes involving chemical strengthening, atmospheric treatments, glazing and quenching were investigated. In some cases strength increases of more than 90% were observed. The thermal shock resistance of some of the samples was improved. Abrasion of the surfaces of some of the treated samples did not result in loss of strength. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 07, 1967
Accession Number
AD0652399

Entities

People

  • Dennis R. Platts
  • Henry P. Kirchner
  • Ralph E. Walker
  • Robert M. Gruver

Tags

DTIC Thesaurus Topics

  • Bodies
  • Ceramic Bodies
  • Ceramic Materials
  • Chemical Reactions
  • Flexural Strength
  • High Temperature
  • Materials
  • Quenching
  • Resistance
  • Shock
  • Shock Resistance
  • Thermal Shock

Fields of Study

  • Materials science

Readers

  • Materials Science (Mechanical Engineering).
  • Materials Science and Engineering.
  • Surface Coatings Technology.