Accession Number : ADA116121

Title :   Sintered Si3N4 for High Performance Thermomechanical Applications.

Descriptive Note : Final rept. 1 Jan 81-1 Jan 82,

Corporate Author : GENERAL ELECTRIC CORPORATE RESEARCH AND DEVELOPMENT SCHENECTADY NY

Personal Author(s) : Pasco,W D ; Greskovich,C D

PDF Url : ADA116121

Report Date : Apr 1982

Pagination or Media Count : 62

Abstract : The gas pressure sintering (GPS) process for dense ( 99%) Si3N4 containing approx. 7 wt% BeSiN2 and 7 wt% SiO2 as sintering aids was scaled-up to develop a property data base for use in thermomechanical applications at high (approx. 1300 deg C) temperatures. The fracture strength in 3-pt bend for test bars approx. 0.6 cm x 0.6 cm x 4.5 cm long was approx. 440 MNm-2 (63,700 psi) for a span length of 3.8 cm. There was little drop ( 15%) in high temperature strength at 1400 deg C in air. The creep resistance was outstanding at 1300 to 1400 deg C, as evidenced by creep rates of approx. 4 x .00001/h for a stress of 207 MPa (30,000 psi) at 1400 C. (Author)

Descriptors :   *SINTERING, *SILICON NITRIDES, *THERMOMECHANICS, GASES, PRESSURE, CREEP STRENGTH, HIGH STRENGTH, HIGH TEMPERATURE, DATA BASES, FRACTURE(MECHANICS), RATES

Subject Categories : Mfg & Industrial Eng & Control of Product Sys
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE