Effect of porosity and microstructure on the microwave dielectric properties of rutile

Wei Luo, Jing Guo, Clive Randall

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The dielectic properties of rutile were strongly affected by porosity and microstructure. The relative permittivity, loss tangent, and temperature coefficient of resonant frequency of titanium oxide in microwave frequency were explored over a broad density range which was controlled through sintering temperature. Permittivity values range between 15 and 115 as the sintering temperature increased from 500 to 1550 °C. The measured permittivity were compared with several types of mixing rules which assumed titania and pores as the constituents. A coherent potential formula was modified to produce the best fit over the largest porosity range. General constitutive formulas were also developed to describe tanδ and TCF and these models work well for intermediate porosity ranges (0.08 < Pore fraction < 0.4); however there were significant deviations at the high and low porosity ranges (Pore fraction < 0.08 and > 0.4). The deviations were attributed to local reduction of the rutile grains and grain boundaries.

Original languageEnglish (US)
Pages (from-to)101-104
Number of pages4
JournalMaterials Letters
Volume200
DOIs
StatePublished - Aug 1 2017

Fingerprint

rutile
Dielectric properties
dielectric properties
Permittivity
Porosity
Microwaves
porosity
microwaves
microstructure
Microstructure
Sintering
permittivity
sintering
Titanium oxides
Microwave frequencies
Temperature
Natural frequencies
Grain boundaries
Titanium
microwave frequencies

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

@article{473a1bd644864a0a97a59641d2680ab2,
title = "Effect of porosity and microstructure on the microwave dielectric properties of rutile",
abstract = "The dielectic properties of rutile were strongly affected by porosity and microstructure. The relative permittivity, loss tangent, and temperature coefficient of resonant frequency of titanium oxide in microwave frequency were explored over a broad density range which was controlled through sintering temperature. Permittivity values range between 15 and 115 as the sintering temperature increased from 500 to 1550 °C. The measured permittivity were compared with several types of mixing rules which assumed titania and pores as the constituents. A coherent potential formula was modified to produce the best fit over the largest porosity range. General constitutive formulas were also developed to describe tanδ and TCF and these models work well for intermediate porosity ranges (0.08 < Pore fraction < 0.4); however there were significant deviations at the high and low porosity ranges (Pore fraction < 0.08 and > 0.4). The deviations were attributed to local reduction of the rutile grains and grain boundaries.",
author = "Wei Luo and Jing Guo and Clive Randall",
year = "2017",
month = "8",
day = "1",
doi = "10.1016/j.matlet.2017.04.113",
language = "English (US)",
volume = "200",
pages = "101--104",
journal = "Materials Letters",
issn = "0167-577X",
publisher = "Elsevier",

}

Effect of porosity and microstructure on the microwave dielectric properties of rutile. / Luo, Wei; Guo, Jing; Randall, Clive.

In: Materials Letters, Vol. 200, 01.08.2017, p. 101-104.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Effect of porosity and microstructure on the microwave dielectric properties of rutile

AU - Luo, Wei

AU - Guo, Jing

AU - Randall, Clive

PY - 2017/8/1

Y1 - 2017/8/1

N2 - The dielectic properties of rutile were strongly affected by porosity and microstructure. The relative permittivity, loss tangent, and temperature coefficient of resonant frequency of titanium oxide in microwave frequency were explored over a broad density range which was controlled through sintering temperature. Permittivity values range between 15 and 115 as the sintering temperature increased from 500 to 1550 °C. The measured permittivity were compared with several types of mixing rules which assumed titania and pores as the constituents. A coherent potential formula was modified to produce the best fit over the largest porosity range. General constitutive formulas were also developed to describe tanδ and TCF and these models work well for intermediate porosity ranges (0.08 < Pore fraction < 0.4); however there were significant deviations at the high and low porosity ranges (Pore fraction < 0.08 and > 0.4). The deviations were attributed to local reduction of the rutile grains and grain boundaries.

AB - The dielectic properties of rutile were strongly affected by porosity and microstructure. The relative permittivity, loss tangent, and temperature coefficient of resonant frequency of titanium oxide in microwave frequency were explored over a broad density range which was controlled through sintering temperature. Permittivity values range between 15 and 115 as the sintering temperature increased from 500 to 1550 °C. The measured permittivity were compared with several types of mixing rules which assumed titania and pores as the constituents. A coherent potential formula was modified to produce the best fit over the largest porosity range. General constitutive formulas were also developed to describe tanδ and TCF and these models work well for intermediate porosity ranges (0.08 < Pore fraction < 0.4); however there were significant deviations at the high and low porosity ranges (Pore fraction < 0.08 and > 0.4). The deviations were attributed to local reduction of the rutile grains and grain boundaries.

UR - http://www.scopus.com/inward/record.url?scp=85018271793&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85018271793&partnerID=8YFLogxK

U2 - 10.1016/j.matlet.2017.04.113

DO - 10.1016/j.matlet.2017.04.113

M3 - Article

AN - SCOPUS:85018271793

VL - 200

SP - 101

EP - 104

JO - Materials Letters

JF - Materials Letters

SN - 0167-577X

ER -