The effect of TiO2 additions on CaO–MgO–Al2O3–SiO2 (CMAS) crystallization behavior from the melt

Abstract

Titania (TiO2) was introduced into a model calcium‐magnesium aluminosilicate (CMAS) glass in additions of 5‐20 wt%. The crystallization behavior of the mixtures was characterized over a series of temperature profiles and compared to that of CMAS alone. X‐ray diffraction, differential scanning calorimetry, light and scanning electron microscopy, and energy dispersive spectroscopy were used to characterize glass and crystalline products. Titania additions in the amount of approximately 12.5‐20 wt% aided in the formation of CaTiO3 from melts equilibrated at either 1300 or 1500°C and cooled at 10°C/min. Holding CMAS + TiO2 (TiO2 ≥ 10 wt%) at 900°C after cooling from 1300/1500°C resulted in the formation of additional crystalline phases including melilite, paqueite, and diopside. Implications for CMAS interactions with thermal and environmental barrier coatings are discussed.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 19, 2018
Source ID
10.1111/jace.16180

Entities

People

  • Elizabeth J. Opila
  • Rebekah I. Webster

Organizations

  • Office of Naval Research
  • University of Virginia

Tags

Fields of Study

  • Materials science

Readers

  • Marine Ecological Systems Migration
  • Powder metallurgy of Titanium alloys.
  • Quantum Chemistry

Technology Areas

  • Microelectronics