| Summary: | Recent years have seen extensive development of new types of electro-mechanical devices, intended for use as sensors rotations and angular rates. They all tend to comprise any type of mechanical resonators which are sensitive to fluctuations in the rotational motion. Achievement of stable characteristics and high performance of these devices requires maintaining of the vacuum inside them at the level of 1…10-4 Pa. In the technology of assembly of such devices different adhesives and sealants are often used. They allow to connect easily and safely parts of different materials and eliminate the risk of thermal or mechanical damage, but at the same time adhesive joints have significant outgassing worsening vacuum inside the device. Although today's global industry produces a large number of different types of adhesives with low outgassing (see, for example, the NASA database [1]), the problem of providing vacuum in devices with internal adhesive joints remains unresolved until the end. The literature contains data describing the outgassing of some heat-resistant adhesives [2-7], which show that even small residual outgassing significantly worsens vacuum inside the device. The diagram (Fig. 1) evaluated according to the data presented in [6, 7] shows the composition and the partial pressure of gas components at ambient temperature inside the device comprising the adhesive joints (adhesive EPO-TEK H74UNF), after 10 years of its operation. In computations, the area of adhesive joints was S=1 мм 2 , the inner volume was V=100 см3 , relative outgassing rates were equal to [3]: ν(H2O)=6.9∙10-6 Pa∙m/s; ν(СО2)=8.9∙10-8 Pa∙m/s; ν(СO)=1.7∙10-7 Pa∙m/s; ν(СxHy)=10-6 Pa∙m/s; ν(H2)=1.2∙10-6 Pa∙m/s; ν(O2)=1.3∙10-10 Pa∙m/s; ν(HF)=1.4∙10-8 Pa∙m/s. As can be seen from the diagram, within 10 years after manufacture the total pressure inside the device increases to about 30 Pa, which inevitably leads to the loss of its functionality
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