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Information × Registration Number 0220U103145, 0115U005659 , R & D reports Title Research opportunities for application factorial experiment during ultrasonic testing of physicomechanical characteristics of multiphase powder materials popup.stage_title Head Galagan Roman M., Кандидат технічних наук Registration Date 20-08-2020 Organization National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute" popup.description2  An experimental sample of an ultrasonic system for diagnosing the physicяl and mechanical characteristics of powdered structural materials was created and studied. Ultrasonic system base on the developed methods and devices of measuring the speed of propagation of an ultrasonic wave and processing the measurement results. The use of the developed system during the testing of physical and mechanical characteristics of powder construction materials allows to reduce by an order of magnitude the random error of measuring the speed of ultrasonic wave propagation and the standard deviation of scattering testing results due to the measuring factor. The variable factors that most influence the measurement error of the ultrasonic wave velocity were selected: the force of pressing the transducer to the object of testing, the mismatch of the measurement base of the size of the acoustic path, sampling rate and the number of ADC bits. The estimation of the last two factors is especially relevant in connection with the use of a discrete orthogonal phase method of measuring the time interval. Other factors, as a result of the analysis, were considered insignificant or those whose influence can be compensated in various ways. The a priori ranking method was used to establish the area for determining the input factors. To test the relationship between the speed of propagation of the ultrasonic wave and the selected factors, it was decided to build a linear model of the factorial experiment, with the number of factor levels equal to 2. The least squares method was used to find the coefficients of the objective function. Thus, by conducting numerical experiments, a linear function of the rate of propagation of ultrasound was obtained, which reflects the degree of influence of factors on the error of the measurement result. The proposed ultrasonic method for measuring the physical and mechanical characteristics of powdered structural materials and created a tool that implements it, al Product Description popup.authors Bohdan Halina A. Galagan Roman M. popup.nrat_date 2020-10-01 Close