Direct laser fusion bonding process of borosilicate glass and Kovar alloy

Direct laser fusion bonding process of borosilicate glass and Kovar alloy was investigated to obtain the optimum parameters. Surface texturing of Kovar alloy through fiber laser was performed for achieving the reliable joining quality. The microstructure of joint interface and fracture morphology were observed by Scanning Electron Microscope (SEM), the distribution of elements was analyzed by Energy Dispersive System (EDS), and the compressive shear strength of joint were tested. The results indicated that the higher laser power, the more Fe₂SiO₄ in the reaction products when the laser scanning rate is fixed. The maximum compressive shear strength of joint reached 5.8 MPa when the laser power was 650 W and scanning rate was 15mm/s. While the maximum compressive shear strength of glass-textured metal joint was 12.9 MPa under the same laser process parameters, which increased by 122.4% compared with the glass-non-textured metal joint.