Accession Number:

AD0747357

Title:

A Study of Interfacial Reactions in Titanium/Sapphire (Al2O3) Composites.

Descriptive Note:

Research memo.,

Corporate Author:

GRUMMAN AEROSPACE CORP BETHPAGE N Y RESEARCH DEPT

Personal Author(s):

Report Date:

1972-07-01

Pagination or Media Count:

46.0

Abstract:

The reactions between sapphire filaments and Ti70A and Ti75A matrices were studied over the temperature range 600 to 1000C for various times. The filament decomposed through diffusion of both aluminum and oxygen into the Ti matrix, resulting in a series of TixAly compounds formed adjacent to the filament with aluminum and oxygen diffusion gradients ahead of the zone. Two rate constants were measured for the reaction zone growth an activation energy of 23 Kcalmole was calculated above 800C and a value of 53 Kcalmole below. It was determined from Microhardness measurements in the matrix that oxygen diffusion was primarily occurring. Unless the embrittling effects of the reaction can be controlled, it appears that Tial2O3 composites will not be a viable system as compared to TiB or tiSiC composites. Author

Subject Categories:

  • Laminates and Composite Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE