Accession Number:

ADA021539

Title:

Effect of Processing Conditions on Microwave Dielectric Properties of Reaction-Sintered Silicon Nitride.

Descriptive Note:

Final rept.,

Corporate Author:

ARMY MATERIALS AND MECHANICS RESEARCH CENTER WATERTOWN MASS

Personal Author(s):

• Messier,Donald R.
• Wong,Philip

Report Date:

1976-02-01

Pagination or Media Count:

8.0

Abstract:

It is shown that unreacted silicon at levels above 0.5 to 0.6 weight percent seriously degrades the dielectric properties of reaction-sintered silicon nitride. The use of fine particle size silicon and various oxide additives were both effective in reducing unreacted silicon. Measurements of dielectric properties by two facilities were in good agreement, and those properties appear adequate for radome applications at temperatures up to the highest temperature of measurement, 1000C.

Descriptors:

• *RADOMES
• *SILICON NITRIDES
• DIELECTRIC PROPERTIES
• ADDITIVES
• ACTIVATED SINTERING

Subject Categories:

• Electrical and Electronic Equipment
• Ceramics, Refractories and Glass

Distribution Statement:

APPROVED FOR PUBLIC RELEASE