PL112319B2 - Method for measurement of elasticity constants - Google Patents

Description

The subject of the invention is a method of measuring constant resonance using the acoustic resonance method. It is known from the patent description of the Polish People's Republic No. 62032 a method of measuring constant resistances, according to which the tested sample supported at four points lying on the knot lines of the vibrating surface is stimulated to the own vibrations of the first and second order and the magnitude of the constant bones the resonance is determined by the ratio of the frequency of the second resonance of natural vibrations to the frequency of the first resonance of these vibrations. The essence of the method according to the invention consists in the fact that the tested sample in the form of a circular plate supported in three vibration nodes stimulates the contactless capacitive method to vibration of the second natural row and these vibrations are perceived by a contactless pickup transducer. The magnitude of the constant resonance is directly determined by the ratio of the frequency of the second resonance to the frequency of the third resonance of these vibrations. The method according to the invention ensures a stable position of the sample even in the case of its deformation caused by large changes in temperature. The method of measuring constant resonance will be closer to the frequency of the third resonance of these vibrations. Fig. 1 shows the image of the second resonance node lines on the test circular sample, in Fig. 2 the image of the third resonance node lines of the same sample, and Fig. 3 the arrangement of the plate support points. The test circular sample is supported by through steel needles at three points W lying on the knot lines of the vibrating surface of the sample. In this sample, the resonance of bending waves of the second order fi is induced, i.e. one in which the knot lines have the form of a circle, and then in the sample the resonance of bending waves of the third order f3tj is induced. one in which the node lines have the form of three intersecting diameters. The fixing points of the sample W are located at the intersection of the node lines of the resonances f2 and d. Then the vibration frequency is measured with the resonance U and f3 and the vibration frequency ratio of the second resonance to the vibration frequency the third resonance is the Poisson constant function. Knowing the geometrical dimensions of the test sample and the density of the tested material, after measuring the Poisson constant, the modulus of elasticity E is determined. Patent disclaimer The method of measuring the constant elasticity of materials consisting in stimulating the sample to its own vibration and determining the constant elasticity on the basis of resonance frequencies, characterized by the fact that the tested the sample is attached to three points (W) located on the nodal lines of the resonances (f2 and f3 stimulate high resonance vibrations of the second order (f2 and third order (f 3) and the frequency of these vibrations is measured, with the elasticity constant being determined by designation of the ratio of these frequencies. \\ 2 M9 Fig4 Bg.2 Fig. 5 Printed work of the Polish People's Republic of Poland. Circulation 120 copies Price PLN 45 PL

Claims (2)

1. Patent claim A method of measuring the constant elasticity of materials consisting in stimulating the sample to its own vibrations and determining the constant elasticities on the basis of resonance frequencies, characterized by the fact that the tested sample is mounted at three points (W) located on the knot lines of resonances ( f2 and f3 are excited to high resonance vibrations of the second order (f2 and third order (f 3) and the frequencies of these vibrations are measured, the constant of the resilience is determined by the ratio of these frequencies. \\ 2 M9 Fig4 Bg. 2. Fig.5 Work. Typographer. UP PRL. Mintage 120 copies Price PLN 45 PL