Ceramic-metal joints Selective

The DB-procedure was optimised in respect with the kinetic requirements and the high-temperature mechanical properties of the Ni-superalloy. From the kinetic point of view, the bonding temperature should be over 1000°C when alumina and transition metals are directly bonded [6]. The bonding procedure was always carried out in high vacuum, better than 2-10 mbar (0.2 mPa). The typical thermal and axial compression cycles are presented in Fig.la. It was experimentally found that the ambient bonding temperature is 1100"C or less due to the fast creep of the superalloy beyond this. The compression for the tests was selected as 10 MPa in ceramic-metal joints and 20 MPa in ceramic-ceramic joints [6]. 

Two Nl-based superalloys (Inconel 600 and 625) were studied for braze alloys In ceramic-metal joints for high temperature applications. These alloys were selected based on their high-temperature performance and ductility. 

By definition, a structural bond involves the formation of a load-bearing joint between high-strength materials, typically metal, wood, ceramic, and certain plastics. The first step in the selection of a joining method should be a comparison of the relative merits of the available techniques.In addition to structural adhesives, these include a number of mechanical fastening methods, such as screws, bolts, nails, staples, and rivets, as well as metal fusion processes. Many of these techniques are usually associated with the joining of metal structures. 

Most materials can be bonded with the correct selection of adhesive, surface preparation and joint design. Metals, plastics, composites, wood, glass, paper, leather and ceramics are bonded commonly. 

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