Research on SiC‐glass‐Al interfacial microstructure and mechanical properties based on two‐step anodic bonding process

Abstract A two‐step anodic bonding process fabricates SiC‐BF33 glass‐Al joints. Analysis confirms perfect bonding among the three materials. The interface appears smooth and defect‐free. Na + depletion layer can be observed in the glass matrix after corrosion by hydrofluoric acid. This depletion layer widens with increasing bonding parameters. The glass‐Al interface exhibits a slightly narrower Na + depletion layer than the glass‐SiC side, with deeper corrosion. The first bonding step demonstrates a higher peak current and shorter time to peak than the second step. Compared with bonded glass‐Al, bonded glass‐SiC shows a higher peak current and a longer time to peak. GD‐OES confirms Al diffusion, while TEM reveals the lattice structure of the glass‐SiC region. Tensile testing consistently fractures at the secondary bonding interface, achieving maximum strength (13.2 MPa) at 450°C and 1000 V.