Aerostatic linear guide made of high performance ceramics by joining
The aim of the work was the development of a high performance aerostatic guide which combines the advantages of the aerostatic lubrication with the properties of ceramics. It will be shown the possibility to create a precision guide by using advanced techniques of manufacture, for example joining with ceramic foils and glass solders, ultrasonic machining and laserdrill. On account of the clean lubricant air, the stable ceramics and the exact aerostatic guide the ceramic guide can be applied in the chemical and food industry, in measuring stages, ultraprecision machines, cryogenics and high temperature engineering. In the following, the soldering by glass solders and joining by a ceramic foil are presented as alternative to two further joining methods. Using these joining techniques enable the production of ceramics/ceramics-, glass ceramics/glass ceramics- and metal/ceramnics bonds. Basis on this joining techniques it will be shown the possibility to creat a precision aerostatic guide of high performance which units the advantages of the aerostatic guide with the properties of ceramics. The use of the ceramic guide leads to an increased performance because the range of operation tends to higher temperatures. Furthermore ceramics are superior materials for protection against wear and corrosion. Accordingly, the most important requirements for a ceramic guide material to meet are high hardness, good resistance to deformation, high corrosion resistance with sufficient resistance to temperature changes and chemical stability. From the precision mechanical view, the lower weight combined with a lower density and a lower thermal expansion are favourable properties in comparison with metal guide materials. As special feature is the positive inertia moment owing to the low specific gravity.