Successful 3-dimensional laser welding of ceramics

In order to use the important properties of ceramics it is sometimes necessary to construct special geometrical forms that cannot be manufactured by conventional methods of shaping. Techniques to join parts of ceramics are often accompanied with a decrease in the material properties. We will describe an absolutely new method of a laser welding technology developed in the Laser Application Centre of Mithweida. Based on an additive- free procedure it allows us to join parts of alumina without any changes of their thermal and mechanical strengths. Two laser beams are used to avoid thermally induced stresses. Furthermore it is possible to join without furnaces and in natural atmosphere. Highly refined laser welded Al2O3- ceramic parts of various shapes will be presented and the thermal influence on the grain structure will be discussed. This new method of laser welding of ceramics opens up a wide field of new applications. A lot of branches of industry have already shown their interest in this promising technique. Most applications are expected with respect to sensor elements generally, for ceramical parts of lamps, in dental technology, and in the protection of electronic elements against high temperatures, abrasion or chemical attacks.