Interface nanostructure of brazed silicon nitride

Nanomorphologies and cristallographic orientations of the brazed interface of silicon nitride (Si ₃N ₄) were analyzed via high-resolution transmission electron microscopy. When Si ₃N ₄ was brazed using an Ag-Cu-Ti alloy, titanium nitride (TiN) nanoparticles were formed adjacent to the ceramic as reaction products, and these nanoparticles were commonly accompanied by C-phase material. The structure of Si ₃N ₄/TiN interface was wavy on an atomic scale, which was considered to provide anchoring points that offered high mechanical strength. The TiN nanoparticles extended along the [0001] axis of Si ₃N ₄. The orientation relationship between TiN and β-Si ₃N ₄ was, as determined from the observed lattice images, that the [110] direction of TiN was parallel to the [0001] direction of Si ₃N ₄. The nature of the crystallographic relationships and interface nanomorphologies were also discussed.