SU998939A1 - Electromagnetic acoustic method of non-destructive ferromagnetic material article thermal tempering quality control - Google Patents

Description

(54) ELECTROMAGNETIC-ACOUSTIC METHOD FOR NON-DESTRUCTIVE QUALITY CONTROL OF THE THERMAL IMPRESSION OF PRODUCTS FROM FERROMAGNETIC MATERIALS

one

The invention relates to acoustic methods. -And means of non-destructive testing and can be used in mechanical engineering to increase the reliability of quality control of thermal processing and strength properties of products made of ferromagnetic steels.

Electromagnetic-acoustic acupuncture; The cue (EMA) method for controlling the quality of the heat shrinkage of ferromagnetic products, d steels, which consists in the fact that an ultrasonic wave is excited by the magnetostricdion interaction at the resonant frequency of this waves in the product and the amplitude of the EMA signal are judged on the quality of the heat output of products C

The disadvantage of this method is the low sensitivity of the control, caused by the weak dependence of the amplitude of the EMA signal on changes in heat setting temperature.

The closest in technical essence to the invention is an electromagnetic-acoustic method of non-destructive testing of the quality of heat-shaking products made of ferromagnetic materials, which implies that the product is subjected to a constant magnetic field, excites ultrasonic vibrations in it, record the acoustic signal at the oscillation resonance frequency in product, determine the phase shift between this signal and the reference and take it into account when monitoring.

The disadvantage of this method is the low reliability of the control in a wide range of heat shrink temperatures, due to the dependence of the control results on the size variations of the same type of controlled products.

The purpose of the invention is to increase the reliability of control in a wide range of heat-shrinking temperatures.

Claims (2)

This del is achieved by the method of non-destructive quality control of heat-shaking products made of ferromagnetic materials according to the electromagnetic-acoustic method, which consists in the fact that the product is affected by a constant magnetic field, excites ultrasonic vibrations in it, register an acoustic signal at the oscillation resonance frequency in the product, the phase shift between this signal and the reference one is determined and taken into account in the course of control; the value of the constant magnetic field is chosen; within 30-3, 5% of the field size corresponding to the maximum amplitude of the acoustic signal on the sample that has passed the heat output at the maximum temperature, and the quality of the heat output determines the vi3 ratio where A is. - the value characterizing the temperature temp; C) - the ratio of the phase shift of the acoustic signal to its value obtained on the sample with the minimum, the temperature of heat; - the ratio of the amplitude of the acoustic signal to its value obtained on the sample with the maximum temperature of the thermal release. The drawing shows a block diagram of a device that implements the proposed method. The device contains a series-connected generator 1 and an emitting EMA converter 2, receiving EMA. converter 3, converter 4 amplitudes of an EMA signal to a constant to a voltage, the input of which is connected to the output of the receiving EMA converter. 3, a phase-shift converter of the EMA signal to a constant voltage, the input of which is connected to the output of the receiving EMA converter 3, an adder 6, whose inputs are connected to the outputs of the converters 4-5, and a source of a constant magnetic field, and the input of the converter 5 connected to the output of the generator 1. The essence of the method lies in the following. From the reference batch of product samples to be monitored for the quality of the heat output, a sample with a maximum heat output temperature is selected and the dependence of the amplitude of the EMA signal on the magnitude of the magnetizing field is removed, the value of the constant magnetic field corresponding to the maximum amplitude of the acoustic signal is determined from this dependence which set the working value of a constant magnetic field p within 30-35% determined from this dependence of the magnitude. When the working magnetic field is set, the phase shift of the EMA signal and the amplitude of the EMA signal at the reference lot are measured, and the measurement results are attributed to the value of the phase shift of the EMA signal received on. the sample with the minimum heat outlet temperature and the amplitude of the acoustic signal obtained on the sample with the maximum tempering temperature in the tempering temperature range of the samples to be monitored, and determine the dependence of the parameter A – H on the tempering temperature. After that, products with unknown tempering modes are monitored and, according to the value of the parameter A, the quality of heat output is measured. To perform these operations, the output of the generator 1 tuned to the oscillation resonance frequency in the controlled product 8, a high-frequency electrical signal which, interacting with the field of the source 7 of a constant magnetic field; excites in the product 8 ultrasonic vibrations. The output signal from the receive EMA converter 3 simultaneously enters the converter 4 amplitudes of the EMA signal into a constant voltage and the converter 5 of the phase shift of the EMA signal into a constant voltage. The signals from the outputs of the converters 4-5, proportional to the values respectively. and H, go to the adder 6. On weekends. The adder 6 signal is judged on the quality of the heat output of the products. Thus, due to the chosen magnetic field and taking into account the dependence of the difference in the ratio of the phase shift of the acoustic signal to its value obtained on the sample with the minimum thermal tempering temperature, and the ratio of the amplitude of the acoustic signal to its value obtained on the sample with the maximum thermal tempering temperature The reliability of the control is enhanced over a wide range of heat shaking temperatures. The invention Electromagnetic-acoustic method of destructive quality control of thermo-release of products made of ferromagnetic materials, concluded that the output is impacted by a constant magnetic field, excites ultrasonic vibrations in it, the acoustic signal is recorded at the resonance frequency of oscillators, with this signal and the reference signal, it is taken into account in the control, which means that, in order to increase the reliability of control in a wide range of heat-shrink temperatures, In a constant magnetic field, the selection is within 30–35% of the pop value corresponding to the maximum amplitude — j de acoustic signal on the sample that has passed the heat output at the maximum temperature, and the quality of the heat output is determined from the ratio A.M-b, & 6639 where 5 10 п № № (п i А - the value characterizing thermal tempering; C) is the ratio of the phase shift of the acoustic signal to its value, obtained by m sample with the minimum temperature of thermal tempering; е, - the ratio of the amplitude of the acoustic signal to its value obtained on the sample with the maximum temperature of the heat release. Sources of information that are considered in the examination 1. Authors certificate of the USSR 785751, cl. Q 01 K 29 / GS, 1978; 2. Authors certificate of the USSR 552553, cl. GOlN 29 / GS, 1975 type)