WO2020200555A1 - Procédé pour contrôler des composants, notamment des corps de retenue d'injecteurs - Google Patents

Procédé pour contrôler des composants, notamment des corps de retenue d'injecteurs Download PDF

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Publication number
WO2020200555A1
WO2020200555A1 PCT/EP2020/053124 EP2020053124W WO2020200555A1 WO 2020200555 A1 WO2020200555 A1 WO 2020200555A1 EP 2020053124 W EP2020053124 W EP 2020053124W WO 2020200555 A1 WO2020200555 A1 WO 2020200555A1
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WO
WIPO (PCT)
Prior art keywords
component
magnetic field
measurements
tested
barkhausen noise
Prior art date
Application number
PCT/EP2020/053124
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German (de)
English (en)
Inventor
Jonas Scherer
Original Assignee
Robert Bosch Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch Gmbh filed Critical Robert Bosch Gmbh
Priority to EP20706632.5A priority Critical patent/EP3948252A1/fr
Priority to CN202080027468.3A priority patent/CN113661390A/zh
Publication of WO2020200555A1 publication Critical patent/WO2020200555A1/fr

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
    • G01N27/725—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables by using magneto-acoustical effects or the Barkhausen effect

Definitions

  • the invention relates to a method for testing components, in particular injector holding bodies, and also to a device which is used in particular to implement such a method.
  • Barkhausen noise is based on the fact that in a slowly changing magnetic field there is a change in the magnetization of a ferromagnetic material, this change occurring in Barkhausen jumps due to the shifts of so-called domains in the material's microstructure, which can be detected as electrical noise signals.
  • a method for testing a component based on Barkhausen noise in which a large number of Barkhausen noise signals are processed, which were or are detected at measurement positions along the surface of the component with a measuring device, with means of a Computer unit from the measurement positions and the associated Barkhausen noise signals, a measurement matrix is formed which contains the recorded Barkhausen noise signals as entries. Furthermore, a plurality of characteristics are specified, each of which represents at least one cause of manufacturing errors in the component, each characteristic being assigned a processing of the measurement matrix, the processing being specific for the respective characteristic, and finally the measurement matrix of the associated with each characteristic is subjected to orderly processing, whereby a severity of the respective characteristic is determined.
  • the The surface of the component to be tested can be scanned in a time-consuming manner at many measuring positions with a measuring device in a locally resolved manner in order to form a measuring matrix which enables a meaningful evaluation.
  • the method according to the invention comprises the method steps of a) performing measurements on the component to be tested, the individual measurements differing from one another by changing at least one input variable, with Barkhausen noise signals of the component to be tested depending on an external magnetic field than Response behavior are recorded, b) determining a respective course of the Barkhausen noise signals in the respective measurements, c) evaluating the respectively determined courses of the Barkhausen noise signals in the individual measurements of the measurement series using at least one predetermined evaluation criterion to determine characteristic values for the component to determine the d) comparing the characteristic values determined on the basis of the at least one pre-determined evaluation criterion for the component to be tested with reference values of reference components v corresponding thereto with regard to the at least one evaluation criterion on at least two different quality classes, with the reference values being or being determined in a learning phase analogous to steps a) to c), and
  • the basic idea of the invention is that the component is magnetized as a function of an external magnetic field and the Barkhausen noise is recorded in each individual measurement of a series of measurements, the successive Change of a magnetic input variable from measurement to measurement of a series of measurements leads to different output signals of the Barkhausen roughness in the respective measurements.
  • the measurements in a series of measurements therefore differ from one another in terms of the different output signals, which - based on empirical studies on components of different quality levels - represent a measure for assessing the material quality of a component.
  • the respective course of the Barkhausen noise signals is determined in each measurement, whereupon the courses are standardized by means of the at least serving to detect distinctive sections or features in the courses Evaluation criteria are analyzed in order to gain characteristic values of the component, which are then compared with characteristic reference values of reference components which belong to a previously known quality class. To obtain the reference values, the reference components were or will be subjected to the same process steps a) to c) as for the test item.
  • the classification is based on the level of the statistically determined degree of correspondence between the characteristic values of the component and the reference values of those reference components that belong to a certain quality class.
  • An advantageous embodiment of the invention can consist in that, as the at least one input variable, the maximum magnetic field strength of the external magnetic field is changed from measurement to measurement within the measurement series, with the respective maximum magnetic field strength causing a reversal point in a hysteresis loop for magnetizing the to test component is set.
  • the turning point in the hysteresis loop marks the so-called saturation and the input variable therefore represents the dynamic range of the magnetic field strength that extends from negative to positive saturation.
  • the maximum magnetic field strength is expediently increased in stages from measurement to measurement as the input variable, the incremental increase taking place evenly spaced apart.
  • An embodiment of the invention that is expedient from an evaluation point of view can consist in the fact that in the measurements the respective profile of the bar house noise signals is formed by an envelope which follows the signal peaks of the bar house noise signals.
  • a large number of evaluation criteria are used, since the reliability of a classification prognosis for a component to be tested increases with the number of evaluation criteria used.
  • Empirical studies show that a reliable classification of test objects is possible if the amplitude difference between a minimum and a maximum in the respective course of the envelope of a measurement is recorded with one of the evaluation criteria, if one with another evaluation criterion from the multitude of evaluation criteria magnetic field strength of the external magnetic field is detected, in which the envelope of a respective course of a measurement has a minimum, and if with yet another evaluation criterion from the multitude of evaluation criteria, an amplitude difference between respective envelopes of measurements within the measurement series with a magnetic field strength of the outer Magnetic field is detected where the envelope of one of the measurements has a minimum.
  • a further evaluation criterion can detect the steepness of edge sections of a maximum in the respective course.
  • a preferred embodiment of the invention is that rolled components are selected as reference components, which define a quality class of high-quality components, since such components have undergone significantly quality-increasing treatment during the manufacturing process due to the defined introduction of residual stresses.
  • the non-roller-burnished components are selected as reference components, which define a quality class of low-quality components, since such components do not undergo a quality-increasing roller burnishing treatment during the manufacturing process.
  • a device which is used in particular to carry out such a method comprises means for changing at least one input variable and means for carrying out measurements on a component to be tested in order to detect bar house noise signals as a function of an external magnetic field, and also means for determining of a respective course of the Barkhausen noise signals in the respective measurements, for evaluating the respectively determined courses of the Barkhausen noise signals of the individual measurements using at least one predetermined evaluation criterion in order to determine characteristic values for the component, for comparing the based on the at least one predetermined evaluation criterion for the component to be tested determined characteristic values with regard to the at least one evaluation criterion corresponding reference values of reference components of at least two different quality classes, and to classify the test component n component based on the comparison, with a data storage device being provided in order to provide the reference values for comparison and classification.
  • the device is suitable, for example, as a test stand for use in a production line.
  • 1A shows a measurement diagram in which a solid measurement curve reproduces Barkhausen noise signals of a component detected by means of a measurement coil as a function of time, the time t being plotted along the abscissa while the Barkhausen voltage U BH is shown along the ordinate, and a dashed measurement curve shows the current curve in an reproduces the coil of an electromagnet as a function of time t, with this current curve impressing the component with the magnetic field that generates the Barkhausen noise,
  • FIG. 1B shows a highly schematic block diagram of a measuring device which is used to record and evaluate measuring diagrams
  • FIG. 2 shows a diagram which has the measurement curve with the Barkhausen noise signals from FIG. 1 and also a curve which, as an envelope, hugs the positive signal peaks of the Barkhausen noise signals of the measurement curve, the time t being plotted along the abscissa, while along the Ordinate shows the Barkhausen noise voltage UBN,
  • FIG. 3 shows a diagram with the envelope of FIG. 2, the magnetic field strength H being plotted along the abs vitesa, while the Barkhausen noise voltage U BN is shown in arbitrary units along the ordina,
  • 4A is a measurement diagram with hysteresis curves which are used to magnetize a respective component and, according to the respective maximum magnetic field strength H max , have control ranges of different sizes, which extend between the reversal points of the respective hysteresis loop, with the ones used to control an electromagnet along the abscissa Current strength I (in ampere units) is plotted as a measure of the magnetic field strength H, while the magnetic flux density B is shown along the ordinate,
  • Fig. 4B is a diagram with the current control according to FIG BN is represented in arbitrary units
  • Fig. 4C is a diagram with the current control according to Fig. 4A korrespondie generating curves of the envelope at different maximum field strength ken for an injector holding body that is not rolled, the magnetic field strength H being plotted in arbitrary units along the abscissa, while the Barkhausen noise voltage U BN is shown in arbitrary units along the ordinate,
  • 5A is a diagram with two curves of an envelope with different maximum field strengths for a rolled injector holder body as a test object to illustrate a first evaluation criterion for detecting one of several characteristics, with the magnetic field strength H in arbitrary units along the abscissa is plotted while the Barkhausen noise voltage UBN is shown in arbitrary units along the ordinate,
  • Fig. 5B is a diagram similar to Fig. 5A, but for a non-rolled Injektorhal tek stresses as the test object to clarify the first evaluation criterion,
  • 6A is a diagram with two curves of an envelope with different maximum field strengths for a rolled injector holding body as a test object to illustrate a second evaluation criterion for detecting one of several characteristics, the magnetic field strength H in arbitrary units along the abscissa is plotted while the Barkhausen noise voltage UBN is shown in arbitrary units along the ordinate,
  • FIG. 6B shows a diagram analogous to FIG. 6A, but for a non-rolled injector holder as the test object, in order to illustrate the second evaluation criterion
  • FIG. 7 shows a flow chart with essential method steps of the method according to the invention.
  • FIG. 1A shows an example of a measurement diagram which uses a measurement curve 1 to reproduce the magnetic response behavior of an injector holding body as a typical component as a function of time t, with the time along the abscissa t is plotted, while the Barkhausen noise voltage UBH of the component is shown along the ordinate;
  • Fig. 1B shows a diagram of a measuring device 10, which is used to record a measurement diagram shown in FIG. 1A and essentially a magnet 11 with an excitation coil 11 ' serving for its current control, a Hall probe 12 arranged on an outer surface of the magnet 11 for Measuring the magnetic field strength H, a sensor coil 13 and an evaluation and control device 15, which is designed in the mecanicsbei game as a processor device or computer device.
  • an injector holding body 14 is received as a test object, which can be magnetized via its key surfaces, while inside the injector holding body 14 the sensor coil 13 is used to measure the Barkhausen noise voltage.
  • the evaluation and control device 15 controls the excitation coil 11 ' via an electrical connection line 15 ' and records measured values of the Hall probe 12 via an electrical connection line 15 " and of the sensor coil 13 via a further connection line 15 "'to output the recorded measured values to evaluate, reference data records stored in an internal reference database 15-1 being retrievable and processable.
  • FIG. 2 shows a diagram with the measurement curve 1 from FIG. 1 and a curve 3 which, as an envelope, follows the positive signal peaks of the Barkhausen noise signals of measurement curve 1 and thereby records the course of the positive signal maxima.
  • the envelope 3 is calculated on the basis of the intensity maxima of the noise signals and their smoothing by means of the evaluation and control device 15 and is used as the basis for the further evaluation, which will be explained below.
  • the envelope 3 has as characteristics successively a rising edge 20, a local maximum 21, a first minimum 22, a second maximum 23, a second local minimum 24, a third maximum 25, and a flank 26 falling from there.
  • FIG. 4B shows a diagram with curve progressions of the envelope 3 at different maximum field strengths H max (as the respective input variable) for a rolled injector holding body, which is classified as a qualitatively good reference component due to the rolling treatment and the internal stresses introduced in a defined manner
  • FIG. 4C shows a diagram with curves of the course of the envelope 3 at different maximum field strengths H max (as the respective input variable) for an injector holding body in which the manufacturing process took place without quality-increasing roller burnishing treatment.
  • the maximum 30 on the right-hand side of the individual curves remains at approximately the same intensity level, but the position of the maximum 30 shifts on the abscissa with a successively higher hysteresis reversal point of the maximum magnetic field strength H max - corresponding to the in 4A shows hysteresis loops - towards higher magnetic field strengths H; for injector holding bodies without rolling treatment, on the other hand, the intensity level of the right-hand maximum 30 'increases successively with increasing magnetic field strength, although its position on the abscissa remains approximately invariant and only the falling flank of the maximum 30 ' shifts towards higher magnetic field strengths H.
  • FIGS. 4B and 4C - as also in the diagrams according to FIGS. 5A and 5B as well as FIGS. 6A and 6B - are based on measurements which differ from one another from a technical measurement point of view, that the input variable, ie the maximum magnetic field strength H max , which defines the positive reversal point of the respective hysteresis loop, is changed in each case in accordance with the hysteresis loops shown in FIG. 4A, which differ by borrowed large modulation ranges differ from each other with regard to their reversal points.
  • H max maximum magnetic field strength
  • the first evaluation criterion one of several characteristics of a respective envelope is determined; This is exemplified by the curve 41 or 41 'of the Einhül ends in Fig. 5A and 5B, with the evaluation criterion denoted by the reference AK1 amplitude difference between a Mi minimum 41-1 or 41 ' -1 and one on the abscissa on the right side to the immediately adjacent peak is detected 41-2, 41 '-2 of the respective envelope.
  • 6A and 6B serve to illustrate two further Ausensekrite rien, which are manifested by the reference numerals AK2 and AK3, and each show a diagram with two curves 50, 51 and 50 ' , 51 ' of an envelope on the one hand for a rolled one Injector holding body (according to FIG. 6A) and on the other hand for a non-rolled injector holding body (according to FIG.
  • the two envelopes in the respective diagrams differing only in that in the respective curve profile 50 and 50 ' one
  • the second evaluation criterion is used to determine another of several characteristics of a respective envelope; by way of example, this is at hand of the curve 50 or 50 'of the envelope in FIGS.
  • the reference numeral AK2 the position of the minimum 50-1 and 50 -l of each envelope along the abscissa, that is, the is magnetic field strength detected or determined, at which the minimum 50-1 and 50 'occurs -l.
  • Such distinctive sections or features can include, for example, the steepness of flanks in the curves.
  • a flow diagram 100 with the essential method steps of the test method according to the invention shows a flow diagram 100 with the essential method steps of the test method according to the invention.
  • a first step 110 a plurality of Barkhausen measurements are carried out on the component to be tested, which differ from one another by changing the input variable;
  • the excitation current in the excitation coil 11 'of the electromagnet 11 and thus the magnetic field strength H is varied in a standardized, graduated manner with each measurement (FIG. 4A), so that in the embodiment - as shown in FIG. 4A It can be seen - six measurements result for each test object, the maximum magnetic field strength H max , ie the control range of the respective underlying hysteresis loop, being increased from 0.5 to 0.9 in 0.1 steps.
  • the signal maxima of the Barkhausen noise signals are recorded for each measurement.
  • the respective course of the signal maxima is calculated for each measurement by, according to a preferred exemplary embodiment, the envelope of the signal maxima of each measurement using measurement curve smoothing. direction is determined.
  • several evaluation criteria - which are manifested in the exemplary embodiment using the reference symbols AK1, AK2 and AK3 - are applied to the courses of the respective measurements in order to determine characteristic values from the courses of the respective measurements.
  • the characteristic values determined on the basis of the evaluation criteria for the courses of the measurements are stored as test data records for the component to be tested.
  • the values determined and stored for the component to be tested are compared with the corresponding reference values of reference components, of which the reference values are determined or have already been determined in accordance with the predetermined evaluation criteria in a training phase in an analogous application of method steps 110 to 140 and in the latter case are stored as reference data sets in the reference database 15-1 of the control and evaluation device 15.
  • the reference components are divided into two quality classes, namely, on the one hand, the quality class of the "good” components, into which those components are classified that have undergone a significantly higher quality burnishing treatment during the manufacturing process for the defined introduction of residual stresses, and on the other hand Quality class of the "bad” components, in which those components are classified that were not subjected to roller burnishing during production.
  • step 150 If the comparison in step 150 shows that the characteristic values determined for the component to be tested are in the range of the reference values of the rolled reference components, the component to be tested is classified as qualitatively “good” in a step 160 that follows immediately; However, if the characteristic values for the component to be tested are outside this classified range and in the range of the reference values for the non-roller-burnished reference components, the component to be tested is classified as qualitatively “poor” in a step 160 ' immediately following.
  • the device 10 shown in Fig. 1B is used to carry out the method 100 and comprises an evaluation and control device 15 interacting with the excitation coil 11 and the magnet 11 ' for changing at least one input variable and for performing measurements on a component 14 to be tested by means of the Hall probe 12 and the sensor coil 13, in order to to detect house noise signals as a function of an external magnetic field, as well as to determine a respective course 3 of signal maxima in the respective measurements, to evaluate the respectively determined courses 3 of the signal maxima of the individual measurements by means of predetermined evaluation criteria in order to determine characteristic values for the component 14 to compare the characteristic values determined on the basis of the predetermined evaluation criteria for the component to be tested 14 with reference values of reference components corresponding to the evaluation criteria, which belong to at least two different quality classes, and to classify the component to be tested 14 on the basis of the comparison, wherein a Database 15-1 in the
  • Evaluation and control device 15 of the device 10 is provided in order to provide the reference values for comparison and classification.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
  • Measuring Magnetic Variables (AREA)

Abstract

L'invention concerne un procédé (100) pour contrôler un composant au moyen du bruit Barkhausen. Le procédé comprend les étapes suivantes : a) la réalisation (110) de mesures sur le composant (14) à contrôler, qui se différencient les unes des autres par la modification d'au moins une grandeur d'entrée, les signaux de bruit Barkhausen du composant (14) à contrôler étant détectés en fonction d'un champ magnétique extérieur, b) la détermination (120) d'une variation respective de maxima des signaux de bruit Barkhausen dans les mesures, c) l'évaluation (130) des variations respectivement déterminées des maxima des signaux des mesures au moyen de critères d'évaluation prédéfinis, afin de déterminer des valeurs caractéristiques, d) la comparaison (150) des valeurs déterminées pour le composant (14) sur la base des critères d'évaluation prédéfinis à des valeurs de référence, correspondant à celles-ci, de composants de référence de différentes catégories de qualité, les valeurs de référence ayant été ou étant déterminées au cours d'une phase d'apprentissage analogue aux étapes a) à c), et e) la classification (160) du composant (14) sur la base de la comparaison dans une des catégories de qualité.
PCT/EP2020/053124 2019-04-05 2020-02-07 Procédé pour contrôler des composants, notamment des corps de retenue d'injecteurs WO2020200555A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP20706632.5A EP3948252A1 (fr) 2019-04-05 2020-02-07 Procédé pour contrôler des composants, notamment des corps de retenue d'injecteurs
CN202080027468.3A CN113661390A (zh) 2019-04-05 2020-02-07 用于对构件、尤其对喷射器保持体进行检验的方法

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102019204902.8 2019-04-05
DE102019204902.8A DE102019204902A1 (de) 2019-04-05 2019-04-05 Verfahren zum Prüfen von Bauteilen, insbesondere von Injektorhaltekörpern

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CN (1) CN113661390A (fr)
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EP2834630B1 (fr) 2012-04-05 2016-01-06 ZF Friedrichshafen AG Procédé d'inspection d'une pièce basé sur le bruit barkhausen

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GB2495292A (en) * 2011-10-04 2013-04-10 Maxim Morozov Calibrating barkhausen noise signals for evaluation of thickness of surface hardened layers of steels
EP2834630B1 (fr) 2012-04-05 2016-01-06 ZF Friedrichshafen AG Procédé d'inspection d'une pièce basé sur le bruit barkhausen

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CN113661390A (zh) 2021-11-16
DE102019204902A1 (de) 2020-10-08

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