Ceramic - metal adhesive joining and their performances

The aim of this work was to produce a layer of ceramic on to the metal surface like macro-coatings with using thick ceramic plates in order to increase the life of the metal?s parts. Low carbon steel was used for substrate material. The macro-coatings were firstly carried out using building ceramics (betebe) for the optimising of the adhesive joints before using silicon nitride (Si3N4) plates. The ceramic plates were produced in the form of a thick hexagonal shape and laid down on top of the relatively thicker metal sheet like a honeycomb structure. Adherence was achieved with the cold resin type adhesives. Bonding behaviour of the joints and their strength were measured using three point bending tests. Series of tests were carried out in order to optimise the joints performance. The factors affecting the adherence of the parts, like a type of the adhesive used, surface topography and geometrical features of the bond surfaces were studied. After optimising the type of the adhesive, the other most important factors were the surface topography and roughness, both of which played important roles on the strength of the joints.