DOCERAM uses different connection technologies to integrate the ceramic components in the technical system, which is in most cases made from steel or other metals. Depending on the ambient parameters (temperature, load) connections are form fit, force fit or bonded. DOCERAM application technicians will support you here in your design task. Thanks to a joint design appropriate for ceramics and the selection of a suitable connection technology, costs are reduced, since high performance ceramic materials are usually only in the component with the highest wear.
DOCERAM has for years employed adhesive connection technologies, like bonding, in the high tensile ceramic-metal joints of positioning pins for automotive technology. Apart from adhesives on epoxy resin or silicone basis, which are temperature-resistant up to about 150° C, ceramic-based adhesives are used too, which in the case of reduced strengths withstand temperatures up to 1400 ° C.
Other adhesive force fit joints, like active soldering, are used if the joint is exposed to high temperatures. Active brazing (Figure 3) can be performed with all DOCERAM high performance materials. In this respect oxide ceramics like Al2O3 or ZrO2 are more suitable on account of the high expansion coefficients in the brazing contact than non-oxide ceramics such as Si3N4 or SSiC.
Force-fit connections, which are usually made by shrinkage, are widespread in ceramic-metal connection technology, since they are easy to produce and the necessarily internal ceramics are exposed to pressure. To design the critical compression-tension transition in the case of protruding ceramic shafts the ceramic specialists of DOCERAM possess special joint geometries enabling the performance potential of the ceramic to be fully exploited. Thanks to programmes developed in-house, the shrink joint is adjusted by the DOCERAM engineers depending on the ambient conditions.