Kinetics of Cristobalite Formation in Sintered Silica

Abstract

The kinetics of the cristobalite transformation are reported for sintered silica glass from 1200°C to 1650°C and plotted as a time–temperature–transformation diagram. The 1200°C–1350°C transformation data were fit to the Johnson–Mehl–Avrami–Kolmogorov expression with an time exponent of 3.0 ± 0.6 and an apparent activation energy of 555 ± 24 kJ/mol for the kinetic constant. The temperature of maximum transformation rate was found to fall between 1500°C and 1600°C. Seeding amorphous silica powder with cristobalite resulted in accelerated transformation kinetics. Silica glass powder containing residual quartz had faster transformation kinetics than fully amorphous powder seeded with cristobalite.

Document Details

Document Type
Pub Defense Publication
Publication Date
Mar 26, 2014
Source ID
10.1111/jace.12889

Entities

People

  • John W. Halloran
  • Ryan C. Breneman

Organizations

  • Georgia Tech
  • Office of Naval Research
  • University of Michigan

Tags

Fields of Study

  • Materials science

Readers

  • Combustion science or combustion engineering.
  • Materials Science and Engineering.