ABSTRACT
Diffusion bonding is a process of joining two similar or dissimilar materials through facilitating an interface cross-diffusion of elemental species at elevated temperature and pressure, hence forming a permanent bond of mating surfaces. The quality of the joint is controlled by the cross-diffusion of interfacial elements. It has been accepted that diffusion bonding is not dominated by only one physical mechanism. The process of diffusion bonding can be divided into three steps those are: physical contact of the surfaces; the activation of the contacting surfaces; and diffusion of the interfacial elements and formation of the joint. In diffusion bonding, the surfaces to be joined must have well-controlled cleanliness and specified flatness. Bonding pressure is an important parameter for the diffusion bonding, especially for bonding of dissimilar materials. Bonding temperature is the most important parameter in a diffusion bonding because this is a thermally activated diffusion and reaction process. Diffusion bonding is a high-temperature/high-pressure diffusion controlled method of joining metals and ceramics.
