NOTES ON THE STUDY AND EVALUATION OF POSITION DETERMINATION SUB-SYSTEMS

Abstract

DESCRIPTORS: (Soli state physics, Electrical properties, Piezoelectric effect, Crystals, *Barium comp un s, *Titanates, *Crystal struc ture.) (Particles, Heat treatment, Processing, Chemical analysis Spectrographic analysis, Phase studies.) (T ESTS, *Thermal expansion, Density, Physical properties.) The electrical properties, especially t e piezoelectric, are epen ent n t only upon the chemical composition of BaTiO3 but also upon the BaTiO3 compounds and unreacted materials present. Some of these properties persisted even after ceramic firing of the test pieces fabricated from the powders. The piezoelectric couplings ere measure . There was n direct correlation between t e coupling and t e density of the material over a wide temperature range. The effects of grain size and grain-size distribution on various parameters of fired BaTiO3 samples are c pared graphically with the as-received or the as-prepared materials. Thermal expansion tests showed that expansion characteristics of BaTiO3 from different rces did not nece arily differ rom eac ot er any m re t an i different lots from the same source. T HE COE FICIENT OF EXPANSION ECREASED ABRUPTLY AT THE Curie Point and t en increased rapi ly. (Author)

Document Details

Document Type
Technical Report
Publication Date
Feb 24, 1961
Accession Number
AD0270220

Entities

People

  • Robert E. Kester

Tags

DTIC Thesaurus Topics

  • Chemical Analysis
  • Chemical Composition
  • Couplings
  • Curie Temperature
  • Electrical Properties
  • Grain Size
  • Heat Treatment
  • Magnetic Properties
  • Materials
  • Phase Studies
  • Physical Properties
  • Piezoelectric Effect
  • Thermal Expansion

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Powder metallurgy of Titanium alloys.
  • Snow Cover Descriptors for Reptiles and Their Illustrations.