Accession Number : AD0779901

Title :   Self-Diffusion in Silicon Nitride.

Descriptive Note : Interim rept. 1 Jan-31 Dec 73,

Corporate Author : AVCO SYSTEMS DIV WILMINGTON MASS

Personal Author(s) : Wuensch,Bernhardt J. ; Vasilos,Thomas

Report Date : APR 1974

Pagination or Media Count : 38

Abstract : Progress is described in the first year of a program designed to obtain simultaneous measurement of Si and N self-diffusion coefficients in silicon nitride. Comparative measurements will be made at a given temperature in a variety of materials. Measurements will also be made as a function of temperature for one well characterized material. Neither Si nor N has an isotope suitable for use as a radiotracer. The stable isotopes Si29 and N15 are therefore being used as tracers. Mass spectrometry applied to sections removed serially from a sample will be used to establish isotope distributions. Determination of N15/N14 is being obtained from N2 using gas spectrometry; measurement of Si29/Si30 is being determined from BaSiF6 with hot filament analysis. (Modified author abstract)

Descriptors :   *Silicon nitrides, Silicon, Nitrogen, Mass spectrometry, Refractory materials, Tracer studies

Subject Categories : Ceramics, Refractories and Glass
      Isotopes
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE