LAUSR

Abstract A new method of pre-cladding amorphous glass and glass-ceramic brazing was invented to obtain a high-reliability bonding of yttrium iron garnet ferrite (YIG) and magnesium titanate ceramic (MTC) at a relatively low temperature of 725oC. The amorphous glass cladding could alleviate the stress generated by thermal expansion difference between the glass ceramic and base materials. The microstructure shows that micron-scale and nanoscale CoFe2O4 phases were dispersed in the glass seam. The joint shear strength reached 117 ± 6.6 MPa due to the enhancement of CoFe2O4 phases, which was twice as that of the joint directly brazed by amorphous bismuth glass. Correspondingly, the joint weak area was transferred from the glass matrix to the vicinity of the interface and the base material, providing a direct evidence that the glass seam was strengthened by the glass ceramic. It is significant for improving high reliability of the microwave devices for long-term service.