LAUSR

Abstract Bismuth-based glasses doped with MgO nanoparticles were designed to realize the in situ growth of MgFe2O4 whiskers with the aim of improving the mechanical and magnetic properties of YIG/YIG joints. The microstructure of the joints and the formation mechanism of MgFe2O4 whiskers were systematically investigated, as well as the mechanical and magnetic properties. The MgFe2O4 nuclei grew along the [001] orientation to form MgFe2O4 whiskers. The shear strength of YIG/YIG joints increased with an increase in doping of MgO nanoparticles, reaching a maximum of 67.5 MPa for the joint brazed with Bi25-21MgO. It indicated that MgFe2O4 whiskers play an important role in strengthening the joints. The magnetic force microscopy (MFM) and vibrating sample magnetometer (VSM) results indicated that the magnetic properties of the brazing seam improved with the growth of in situ magnetic MgFe2O4 whiskers. The magnetism of YIG/YIG joints could be intensified by brazing with Bi25-21MgO composite glass.