Accession Number:

ADA281470

Title:

Electromagnetic Processing of Refractory Metal Silicide/Oxide Composites

Descriptive Note:

Final rept. 1 Aug 1990-31 Jan 1994

Corporate Author:

TEXAS UNIV AT EL PASO

Personal Author(s):

Report Date:

1994-03-28

Pagination or Media Count:

22.0

Abstract:

The electromagnetic processing of refractory metal ceramic materials within -the hot zone of an induction furnace was investigated by modeling the electromagnetic field at high temperatures i,e., 1800 deg C and by characterizing the microstructure after annealing zirconium disilicide powder which sustained the field. The finite element analysis FEA of the electromagnetic field within the furnace determined that the magnetic vector potential was significant just outside the center axis. The analysis also determined that the magnetic vector potential can substantially generate a temperature rise within the zirconium disilicide phase because of its conductivity at 1800 deg C. With ceramic powders averaging in size of 3-l0 microns, a reaction couple of ZrSiSiO2 was prepared in-situ and annealed at temperatures greater than 1900 deg C. The reaction couple developed an interdiffusion zone near the SiO2air interface and an inner core. Within the interdiffusion zone, reaction products consisting ZrO2 and SiO2 precipitates resulted from the diffusion of oxygen through a silica layer. During the annealing process, the couples inner core consisted of ZrSi and liquid silicide, which upon solidification resulted in ZrSi, ZrSi2 and a SiZrSi2 eutectic structure.

Subject Categories:

  • Laminates and Composite Materials
  • Electromagnetic Pulses

Distribution Statement:

APPROVED FOR PUBLIC RELEASE