Hp. Xiong et al., DEVELOPMENT OF A NEW CUNITIB BRAZING ALLOY FOR JOINING SI3N4 TO SI3N4, Metallurgical and materials transactions. A, Physical metallurgy andmaterials science, 29(10), 1998, pp. 2591-2596
Joining Si3N4 to S3N4 was carried out initially with a Cu34Ni27Ti39 br
azing alloy prepared by double melting under a vacuum condition. Howev
er, the strength of the joints was not as high as expected. The causes
were studied. Based on the results of the analysis, a CuNiTiB brazing
filler metal was designed. The Si3N4/Si3N4 joints were then brazed wi
th this new brazing alloy in the paste form, and joints with a three-p
oint bend strength of 338.8 MPa at room temperature were obtained. The
interfacial reactions of the joint are also discussed. With the rapid
ly solidified foils of the brazing alloy, the bend strength of the Si3
N4/Si3N4 joints under the same brazing conditions is raised to 402 MPa
at room temperature. The Si3N4/Si3N4 joints brazed with this newly de
veloped brazing alloy exhibit a rather high and steady bend strength (
about 406 MPa) at 723 K.