Бышов Николай Владимирович Byshov Nikolay Vladimirovich д.т.н., профессор dr.tech.sci., professor РИНЦ SPIN-код=1630-3916 RSCI SPIN-code=1630-3916 Борычев Сергей Николаевич Borychev Sergey Nikolaevich д.т.н., профессор dr.tech.sci., professor РИНЦ SPIN-код=9426-9897 RSCI SPIN-code=9426-9897 Кокорев Геннадий Дмитриевич Kokorev Gennady Dmitrievich д.т.н., доцент dr.tech.sci., assistant professor РИНЦ SPIN-код=9173-7360 RSCI SPIN-code=9173-7360 Колотов Антон Сергеевич Kolotov Anton Sergeevich к.т.н. cand.tech.sci. РИНЦ SPIN-код=7869-6590 RSCI SPIN-code=7869-6590 Колупаев Сергей Васильевич Kolupaev Sergey Vasilevich к.т.н. cand.tech.sci.

We focus on the origin and sources of surface contamination and defects causing the failure of MEMS electrostatic switches. The morphology, and elemental and chemical compositions of the contacting surfaces, conducting paths, and other parts of switches have been characterized by means of SEM, EDXA, and XPS in order to understand the difference between the data collected for the devices that had passed the electrical conductivity test and those found to be defective. C, O, Al, Ca, Ti, Cu, and some other impurities were detected on the details of defective switches. Contrariwise, the working switches were found to be clean, at least on the level of EDXA and XPS sensitivity. The main sources of surface contamination and defects were incompletely deleted sacrificial layers, substrate materials, and electrolytes employed for Rh plating of the contacts. The negative influence of foreign microparticles, especially alumina and copper oxides, on the conductivity and porosity of contacts was highlighted.

The purpose of the study is to increase the reliability of the steering system. The article reflects scientifically based recommendations for improving the design of steering. The research method is theoretical studies performed on the basis of the provisions, laws and methods of theoretical mechanics, hydraulics, heat engineering, power flow theory and mathematical analysis. The article presents the results of theoretical studies on the temperature regimes of a hydraulic power steering (HPS), the results of which establish the analytical relation between the temperature pressure of the working fluid and the efficiency coefficient of the HPS. As a result, knowing the temperature of the working fluid, it is possible to determine the efficiency of the HPS in any of its operating modes. The analysis shows that in order to increase the efficiency of the HPS it is necessary to lower the temperature of the HPS working fluid. To this end, a device is developed aimed at improving the efficiency of the cooling fluid in the power steering and allowing increasing the efficiency of the HPS.