Accession Number : ADA311711

Title :   Silicon Nitride Joining Using a Sr-Celsian-Based Glass Interlayer,

Descriptive Note : Thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Quillen, Brian G.

PDF Url : ADA311711

Report Date : JUL 1996

Pagination or Media Count : 88

Abstract : Si3N4 was successfully joined to itself using a SiO2-SrO-Al2O3 glass composition. Two compositions were evaluated as joining agents, designated SAS-5 and SAS-10 with compositions of 51:44:5 and 49:41:10 weight % SiO2:SrO:Al2O3, respectively. Microstructure of the joint region was examined by electron microprobe and X-ray diffraction. Contact angle measurements and glass characterization, including differential thermal analysis (DTA), dilatometer thermal expansion measurements and crystallization experiments, were used to evaluate each glass composition. Si3N4 plates were joined using interlayers of SAS-5 and SAS-10 glass powder ground to 75 micrometers particle size. Joining was carried out at 1450 deg C in a flowing N2 atmosphere with an applied load of only 0.01 MPa for each glass. Maximum room temperature strengths of 470 and 378 MPa were achieved in four-point bending tests for the SAS-5 and SAS-10 bonded joints, respectively.

Descriptors :   *GLASS, *BONDED JOINTS, *JOINING, *STRONTIUM, *SILICON NITRIDES, MEASUREMENT, MICROSTRUCTURE, LAYERS, SILICON DIOXIDE, X RAY DIFFRACTION, TEST METHODS, THESES, CRYSTALLIZATION, BENDING, ROOM TEMPERATURE, CHEMICAL COMPOSITION, OXIDES, ALUMINUM OXIDES, STRENGTH(GENERAL), MICROPROBES, DIFFERENTIAL THERMAL ANALYSIS, ELECTRON PROBES, DILATOMETERS.

Subject Categories : Inorganic Chemistry
      Physical Chemistry
      Ceramics, Refractories and Glass
      Crystallography
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE