SU1652899A1 - Device for determining temperature dependence of material elasticity modulus - Google Patents

Abstract

The invention relates to the study of the physical properties of a material using ultrasonic vibrations and can be used to determine the temperature dependences of the elastic moduli of solids. The aim of the invention is to increase the measurement languor by reducing errors associated with errors in determining the temperature of material samples. The device contains two magnetostrictive transducers and an acoustic communication line, by means of which the longitudinal acoustic oscillations of the latter are excited in the sample by using automatic tuning. set-up wack. Often, the re of natural oscillations of the sample under study and serve as an informative parameter for determining the elastic modulus of material samples. Simultaneously, n lines of the g line are excited in torsional vibrations and time intervals are measured by the echo signals measured by the sample or 2% with

Description

The invention relates to the study of the physical properties of a material using ultrasonic vibrations and can be used to determine the temperature dependences of the elastic moduli of solids.

The purpose of the invention is to improve the measurement accuracy by reducing errors. associated with errors in determining the temperature of material samples.

FIG. 1 shows a block diagram of an apparatus for determining the temperature dependence of the elastic modulus of materials; in fig. 2 - timing diagrams for the operation of the device.

Device for determining the temperature dependence of the elastic modulus of the material

Riala contains a magnetostrictive transducer connected in series 1. limiting amplifier 2. shaper 3 pulses, inverter 4 and AND element 5. sequentially connected generator 6, second shaper 7 pulses, second inverter 8 and second element 9 AND connected to the second output of generator 6 frequency meter 10, a heater 11, an acoustic line 12 of communication with a reflector 13, connected to the output of the amplifier-limiter 2 serially connected counter 14, read-only memory 15, integrator 16, control circuit 17 tim and digital to analog converter 18, whose output is connected to the input of oscillator 6 connected in series

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the starting pulse generator 19, the second generator 20 and the second magnetostriction converter 21, connected to the output of the latter, are connected in series to the second amplifier-limiter 22, trigger 23 and memory register 24, connected to the second output of trigger 23 successively connected matching circuit 25 and the second counter 26, the output of which is connected to the second input of the memory register 24, the third generator 27 connected in series, the first and second programmable counters 28, 29 and the modulator 30, the output of which is connected to the input first magnetostrictive prooozopa

Т01Я 1 ОД1 ПМ1 | ПТ) J) 1 Г I Mr I M1 32

the output of which is connected to you per hour of 10 and peiistrts 24 l and, dd is muted to the inputs of the first and most programmable counters 28 and 24, tnupon the output of the permanent storage device 15 is connected to the second input / circuit 17 control, third and thursday i in ti, i no one hundred and other memorizing ycipcucrpa 15 are connected respectively to the second y of tripler 23 and to the second inputs in pi ui o and second shapers 3 and 7 UMI / li, the first and second outputs the first .ch, c, pa b are connected to the second p / odlm i,

S UTOPOIO npOlpaMMUpv fn, i;

the counter 29 and the module Jurassic 30, the input of the rotator 31 is connected to the output of the intruder 20, and the output to the second input of the second limiting amplifier 22, the output of the third generator 27 is connected to the second coinciding circuit 25, coinciding, and the output of the PGM is a grammable counter 29 is connected by g cc equaling the inputs of the second i uu h. g shaper 19 imgg / tigip i, h moves of the first and wiry firm) -. and

3 PULSES ARE CONNECTED WITH COOiBc V I .1,1, SECOND INPUT SECOND AND LIEPBOn., E- .JH

And 5, 9, and the first and second MSI ps i-armed transducers 1 and 21 are installed coaxially on one of the acoustic communication lines 12, the second end of which is placed in the heater 11 and npt d is assigned to the acoustic communication with test sample 33 Position 34 denotes a system bus for the number of parts of the device with a recorder, voi-riy, in particular, can be sent to an external data processing device. Control circuit 17 could be implemented in the form of reverse counters.

The device operates as follows.

Sample 33 of the investigated May is pn, in (, and is connected with line VI and HI on which is at distance I; from specimens jc

Reflector 13 is installed. A heater 11 is placed in sample 33 and subjected to heating. A sinusoidal signal from the output of a continuous oscillator 6 is fed to a modulator 30, in which a radio pulse is generated, whose duration is set by a programmable counter 29 This radio pulse is converted into an acoustic signal in a first magnetostrictive converter 1 which, via link 12, enters sample 33 and initiates longitudinal vibrations therein. Synchronously with the beginning of the radio pulse, determined by the front of the signal at the input of the modulator 30, the pulse-forming waveform U 1 fi of the pulses Zgpchtkz triggers the transfer of the lenepaiop 20 to the generation mode, HI.) Excited by the incoming input B) of the magnetostriction transform, triggered; Thus, on line 12, at the same time, longitudinal oscillations in forg, ndioig-dpul st and torsional oscillations in the frame of a single pulse begin

ratlichie in speed of propagation 1M DM | HI i and torsional torsion in the Issue d, (otipaii ,, ibe. Those vozmszh chigt. P, iTHfrrn, and time processing

1i Mr. i 1) pnchto1o ts female ignal fig p O

G i. 4 longitudinal oscillations from the trap nn 13 are insignificant and do not affect the resonant picture / j signal of the signal and the scattering (–rutual oscillations of the u - (ІG-1. Hchpom inertia on the studied / of what happens

The pijna signal is longitudinally co- numfi fi 2 nj t c „igal free (zat chng), sch.1- i. Each sample of sample 33 is output from f i to n ioci pin of the converter 1 through (.. 1 / Pc Hd G LOD amplifier of the limiter

2for-1) n1 and 1, its rectangular pulses from it (Fig. 2e; These pulses are received per circuit and the counter 14 whose diode is connected to the corresponding address. Permanent memory device H 15 (ri3V) Each pulse in the reflected signal Corresponds to the pre-recorded K) Dow combination at outputs 1G, City from the fourth output of ROM 15 (FIG. 2 / m enters the trigger inputs of the formers 7 and 3 pulses that form C (l V – l from the output / power signal) It also has gel 2 and generator signal 6 rectangular pulses equal in dmit / s ms i and a specified number n of periods of input: s. signals. At the beginning of the former, a pulse with a duration pA is formed, and at the output of the former, 3 is a pulse with duration dv (here n is the number of pulse signals, A is the period of the generator signal 6, V - the period of the signal of damped oscillations of the sample 32), These rectangular pulses are fed to the inputs of inverters 8 and 4, and the signal from the output of the pulse former 7 is fed to the input of the AND 5 circuit together with the pulseformer’s inverter 4 inverter 4, and the outgoing signal The driver of the pulse generator 3 is fed to the input of the circuit AND 9 together with the signal of the pulse former 7 inverted by the inverter 8. As a result, short pulses are generated at the outputs of the circuits And 9, 5, the duration of which is the same only when the duration of the rectangular pulses pA and pV equal to each other. The pulses from the output of the circuit AND 9 are fed to a non-inverting circuit and the circuit from AND 5 to the inverting inputs of the integrator 16. The signal from the output of the integrator 16 is fed to the information input of the circuit 17 of the digital-to-analog control Converter 18 responding to a positive or negative value of the output signal of the integrators 1G. Depending on this, with “ohm 17 uppagu or DAC at the moment of its occurrence at the second output of ROM 15 (FIG. 2z), increase or decrease its output code nor: up; So on the DAC 18 input Thus, the voltage variation t l of the control input of the generator dd with the DAC 18 output, OS / ShTEM, and the continuous generator 6 is synchronous with the frequency of continuous damped oscillations sample 32 Frequency of sending probing mi-coups of torsional and longitudinal oscillations oip is tied with the time of passage of pulses along link 12, is set by nepi programmed counter 28 Its input is connected to the output of oscillator 27 of reference frequency At the output of programmable counter 28, by the counting input of a programmable counter 29, the oscillation frequency is equal to the frequency of sending the probe pulses

Conversion of cr / tilting is carried out in a magnetostrictive transducer 21. Its output through the amplifier-limiter 22 is connected to the clock input of the trigger 23 The reset input of the trigger 23 is connected to the third output of the ROM 15 Such a trigger enable circuit allows you to receive a signal on its direct output, duration which is equal to the time Tz between the first and second reflected signal n mm

torsional vibrations (Fig. 2i). A single-oscillator 31 connected between the synchronizing output of the generator 20 and the blocking input of the amplifier-limiter 22 serves to block the latter at the moment of excitation of the generator 20 of a short pulse. The coincidence circuit 25 receives a signal from the output of the trigger 23 and a signal from the output of the generator 27 of continuous oscillations of the reference frequency. At the output of the matching circuit 25 connected to the counting input of the counter 26, a sequence of pulses is obtained (Fig. 2k). Code outputs of the counter 26 are connected to the input

memory register 24 Reset counter 26 is performed by a signal from the output of the programmable counter 29 The input information is recorded in register 24 by a signal from the inverting output of the trigger 23 and the signal propagation delay is sufficient to trigger the comparison and counter circuit 25. trunk 34 by writing control layers to registers of programmable counters 28 and 29 The values of the modulus of elasticity are calculated by the formula

t 4 G /) G, where I is the length of the sample

p is the density of the sample material,

f frequency of oscillation of the oscillator (generator frequency 6)

The temperature is determined by the graduated gradient to pi.

chpi temperature interval Efemechi Znac tenne-time interval is read from memory register 24. The values of the modulus of elasticity and its corresponding temperature point are output via system bus 34 to the recorder 32

The invention makes it possible to step up the measurement accuracy due to better heat exchange between sample 33 and the temperature sensor served by the portion of the communication line 12 immediately adjacent to the sample under study.

Claims (1)

The invention The device for determining the temperature dependence of the modulus of elasticity of materials, containing in series the first magnetostriction transducer, the first amplifier-limiter, the first driver pulses, the first inverter and the first element And serially connected the first generator, the second pulse shaper, the second inverter and the second element And connected to the second output The generator frequency meter and heater, the outputs of the first and second pulse shapers are connected to the second inputs of the second and first elements, respectively, characterized in that, in order to improve measurement accuracy by reducing errors associated with errors in measuring the temperature of material samples, it is equipped with an acoustic line connection with the reflector connected to the output of the first amplifier-limiter connected in series by the first counter, permanent storage device, first integrator, circuits control and a digital-to-analog converter, the output of which is connected to the input of the first generator, connected in series by the starting pulse shaper, the second generator and the second magnetostrictive converter connected to the output of the last in series by the second amplifier, trigger, trigger and memory register connected to the second output trigger sequentially connected by a coincidence circuit and a second counter, the output of which is connected to the second memory register input, edovatelno connected third generator, first and second programmable counters and Rui modulator output which is connected to the input of the first magnetostrictive converter, a single vibrator and a recorder whose output is combined with the outputs of the frequency meter and the memory register and connected to the inputs of the first and second programmable counters, the second output of the permanent memory device is connected to the second input of the control circuit, the third and the fourth outputs of the permanent storage device are connected respectively to the second input of the trigger and to the second inputs of the first and second pulse shapers, the first and second outputs n The first generator is connected to the second inputs of the second programmable counter and modulator, the one-shot input is connected to the output of the second generator, and the output is connected to the second input of the second amplifier - limiter, the third generator is connected to the second input of the coincidence circuit, and the output of the second programmable counter is connected to the second counter and driver for starting impulses, and the first and second mast-contraction transducers are installed coaxially at one end of the acoustic line chi. The second horse of which is placed in the heater and is intended for acoustic communication with the sample under study. 6 b g four ppppppppppppppppp lp spiny FIG. 2