CN114813921A - Cold-rolled steel sheet yield strength detection method based on multi-frequency eddy current technology - Google Patents
Cold-rolled steel sheet yield strength detection method based on multi-frequency eddy current technology Download PDFInfo
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Abstract
本发明提供了一种基于多频涡流技术的冷轧钢板屈服强度检测方法，在移动中的带钢一侧安装涡流探头，利用检测板对涡流探头进行多组不同频率的激励，并定时返回检测到的涡流探头实部和虚部的特征值变化，将涡流探头实部和虚部的特征值分别记为电磁激励特征值；将多组在线检测的电磁激励特征值作为输入值带入BP神经网络模型得到当前带钢的屈服强度。本发明考虑了对影响涡流检测信号的提离参数进行修正，并考虑了带钢厚度的影响，不依赖机组的工艺实时参数，实现在线精确测量带钢屈服延伸率的目的。
The invention provides a method for detecting the yield strength of cold-rolled steel plates based on multi-frequency eddy current technology. An eddy current probe is installed on one side of the moving strip, and the eddy current probe is excited by multiple groups of different frequencies by means of the detection plate, and the detection is returned periodically. The eigenvalue changes of the real part and imaginary part of the eddy current probe are obtained, and the eigenvalues of the real part and imaginary part of the eddy current probe are recorded as electromagnetic excitation eigenvalues respectively; the electromagnetic excitation eigenvalues of multiple groups of online detection are taken as input values. The network model obtains the yield strength of the current strip. The invention takes into account the correction of the lift-off parameter affecting the eddy current detection signal, and the influence of the thickness of the strip, and does not depend on the real-time process parameters of the unit, so as to achieve the purpose of accurately measuring the yield elongation of the strip on-line.
Description
技术领域technical field
本发明涉及无损检测技术领域，具体是一种基于多频涡流技术的冷轧钢板屈服强度检测方法。The invention relates to the technical field of non-destructive testing, in particular to a method for detecting the yield strength of a cold-rolled steel plate based on a multi-frequency eddy current technology.
背景技术Background technique
带钢的屈服延伸率，是指呈现明显屈服的金属材料，屈服开始至均匀加工硬化开始之间引伸计标距的延伸与引伸计标距之比的百分率。The yield elongation of the strip refers to the percentage of the ratio of the extension of the extensometer gauge length to the extensometer gauge length between the onset of yielding and the onset of uniform work hardening for metallic materials that exhibit significant yielding.
当前国内钢铁企业对冷轧薄带钢的屈服延伸率(Ae)的检测主要是切样离线试验法，是目前广泛采用的方法。即在一卷带钢的某个部位，如头、尾切样，然后送到实验室进行离线测试，获取试样的屈服延伸率，由此来推断一卷带钢的屈服延伸率。At present, the detection of yield elongation (Ae) of cold-rolled thin strip steel by domestic iron and steel enterprises is mainly the offline test method of cutting samples, which is a widely used method at present. That is, a certain part of a roll of strip steel, such as the head and tail, is cut, and then sent to the laboratory for offline testing to obtain the yield elongation of the sample, thereby inferring the yield elongation of a roll of strip steel.
屈服延伸率的试样离线拉伸测试法，测试原理如图1所示，说明如下：对于不连续屈服的材料，从力-延伸图上均匀加工硬化开始点的延伸减去上屈服强度ReL对应的延伸得到屈服延伸率Ae。均匀加工硬化开始点的延伸通过在曲线图上，经过不连续屈服阶段最后的最小值作一条水平线或经过均匀加工硬化前屈服范围的回归线，与均匀加工硬化开始处曲线的最高斜率线相交点确定。屈服点延伸除以引伸计标距Le得到屈服延伸率。The off-line tensile test method for specimens of elongation at yield, the test principle is shown in Figure 1, and the description is as follows: For discontinuously yielded materials, the extension of the starting point of uniform work hardening on the force-extension diagram is subtracted from the upper yield strength ReL corresponding to The elongation at yield Ae is obtained. The extension of the onset point of uniform work hardening is determined by drawing a horizontal line on the graph through the last minimum value of the discontinuous yield stage or the regression line of the yield range before uniform work hardening, and the point of intersection with the line of the highest slope of the curve at the onset of uniform work hardening . The yield point extension is divided by the extensometer gauge length Le to obtain the yield elongation.
切样离线试验法的优点是简单，结果直接，且精度高。但这种方法存在如下弊端：其一，数据时滞大，对生产过程的帮助有限，在线控制更无从谈起。其二，数据不完整，仅能反应一卷带钢头、尾的值。其三，剪切浪费。机组在生产时，由于某种原因停机或者低速生产，为了维持“头、尾合格，则中间也合格”的经验判断，此时通常要切除一段“疑似不合格”的带钢。切多少没有判断标准，只能尽量多切，显然造成了浪费。其四，需要全天候有人在机旁作业，劳动强度高，人工成本高。The advantages of the cut sample offline test method are simplicity, direct results, and high precision. But this method has the following drawbacks: First, the data time lag is large, the help to the production process is limited, and online control is impossible. Second, the data is incomplete, and can only reflect the value of the head and tail of a coil of steel. Third, cutting waste. When the unit is in production, for some reason, it stops or produces at a low speed. In order to maintain the empirical judgment of "the head and the tail are qualified, the middle is also qualified". At this time, a section of "suspected unqualified" strip is usually cut off. There is no standard for judging how much to cut, so we can only cut as much as possible, which is obviously a waste. Fourth, it is necessary to have people working by the machine around the clock, which is labor-intensive and labor-intensive.
发明内容SUMMARY OF THE INVENTION
本发明为了解决现有技术的问题，提供了一种基于多频涡流技术的冷轧钢板屈服强度检测方法，考虑了对影响涡流检测信号的提离参数进行修正，并考虑了带钢厚度的影响，不依赖机组的工艺实时参数，实现在线精确测量带钢屈服延伸率的目的。In order to solve the problems of the prior art, the present invention provides a method for detecting the yield strength of a cold-rolled steel plate based on a multi-frequency eddy current technology, which takes into account the correction of the lift-off parameter affecting the eddy current detection signal and the influence of the thickness of the strip steel. , does not depend on the real-time process parameters of the unit, and realizes the purpose of accurately measuring the yield elongation of strip steel online.
本发明在移动中的带钢一侧安装涡流探头，利用检测板对涡流探头进行多组不同频率的激励，并定时返回检测到的涡流探头实部和虚部的特征值变化，将涡流探头实部和虚部的特征值分别记为电磁激励特征值；将多组在线检测的电磁激励特征值作为输入值带入BP神经网络模型得到当前带钢的屈服强度。The invention installs the eddy current probe on one side of the moving strip, uses the detection plate to excite the eddy current probe with multiple groups of different frequencies, and returns the detected eigenvalue changes of the real part and the imaginary part of the eddy current probe at regular intervals. The eigenvalues of the part and the imaginary part are respectively recorded as the eigenvalues of the electromagnetic excitation; the eigenvalues of the electromagnetic excitation detected by multiple groups of online detection are taken as input values and brought into the BP neural network model to obtain the yield strength of the current strip.
进一步改进，所述的BP神经网络模型将冷轧薄带钢屈服延伸率与多个检测频率的涡流检测特征值对应，通过输入当前带钢厚度参数来控制变量，建立BP神经网络数学模型。Further improvement, the BP neural network model corresponds the yield elongation of cold-rolled thin strip steel to the eddy current detection characteristic values of multiple detection frequencies, and the BP neural network mathematical model is established by inputting the current strip thickness parameters to control the variables.
进一步改进，所述的电磁激励特征值选择4个频率作为多频涡流的检测频率，使用四个频率点下所检测到的4个实部特征值和4个虚部特征值作为电磁激励特征值，每个频率的每个特征值输出为一个曲线信号，每一个曲线信号通过定义来转换为一个特征值参数。Further improvement, the electromagnetic excitation eigenvalue selects 4 frequencies as the detection frequency of the multi-frequency eddy current, and uses the 4 real part eigenvalues and 4 imaginary part eigenvalues detected under the four frequency points as the electromagnetic excitation eigenvalues , each eigenvalue of each frequency is output as a curve signal, and each curve signal is converted into an eigenvalue parameter by definition.
进一步改进，所述的电磁激励特征值包括15Khz激励频率下测得的涡流实部和虚部特征值，30Khz频率下测得的涡流实部和虚部特征值，60Khz频率下测得的涡流实部和虚部特征值，95Khz频率下测得的涡流实部和虚部特征值。Further improvement, the electromagnetic excitation eigenvalues include the real and imaginary eigenvalues of the eddy current measured at an excitation frequency of 15Khz, the real and imaginary eigenvalues of the eddy current measured at a frequency of 30Khz, and the real and imaginary eigenvalues of the eddy current measured at a frequency of 60Khz. Part and imaginary eigenvalues, real and imaginary part eigenvalues of the eddy current measured at 95Khz frequency.
进一步改进，在带钢屈服强度检测的过程中，涡流探头与带钢之间的距离，即提离，随时间无序变化，通过多个特征值中对屈服强度不敏感而对提离较为敏感的特征值，来对当前提离值进行预测，并反馈到系统中来对预测结果进行补偿。Further improvement, in the process of testing the yield strength of the strip, the distance between the eddy current probe and the strip, that is, the lift-off, changes disorderly with time, and is not sensitive to the yield strength but more sensitive to the lift-off through multiple eigenvalues. , to predict the current lift-off value, and feed it back to the system to compensate the prediction result.
本发明有益效果在于：The beneficial effects of the present invention are:
1、通过对运行的带钢进行多频涡流无损检测，实时获取多个频率下涡流检测的特征值，同时对涡流检测信号进行了扩展，考虑了对影响涡流检测信号的提离参数进行修正，并考虑了带钢厚度的影响，所开发的方法不依赖机组的工艺实时参数，实现在线精确测量带钢屈服延伸率的目的。1. By performing multi-frequency eddy current nondestructive testing on the running strip, the eigenvalues of eddy current testing at multiple frequencies are obtained in real time, and the eddy current testing signal is expanded at the same time, and the lift-off parameters that affect the eddy current testing signal are considered. Considering the influence of strip thickness, the developed method does not depend on the real-time process parameters of the unit, and achieves the purpose of accurately measuring the yield elongation of strip on-line.
2、在10％的相对误差精度范围内，样本合格率为90％以上。2. Within the relative error accuracy range of 10%, the sample pass rate is over 90%.
3、应用在冷轧带钢机械性能质量在线检测系统中，对冷轧带钢屈服延伸率等指标进行实时在线检测，实现钢板生产质量的连续检测、分类和记录，对于提高生产效率、产品质量以及产品竟争力将起到非常积极的作用。3. Applied in the online testing system for mechanical properties and quality of cold-rolled strip steel, it can conduct real-time online detection of the yield elongation and other indicators of cold-rolled strip steel, so as to realize the continuous detection, classification and recording of steel plate production quality, which is helpful for improving production efficiency and product quality. And product competitiveness will play a very positive role.
附图说明Description of drawings
为了更清楚地说明本发明实施例中的技术方案，下面将对实施例中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其它的附图。In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.
图1为屈服延伸率测试原理图。Figure 1 is a schematic diagram of the yield elongation test.
图2为涡流检测原理图。Figure 2 is a schematic diagram of the eddy current detection.
具体实施方式Detailed ways
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其它实施例，都属于本发明保护的范围。The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.
本发明在移动中的带钢一侧安装涡流探头，利用检测板对涡流探头进行多组不同频率的激励，并定时返回检测到的涡流探头实部和虚部的特征值变化，将涡流探头实部和虚部的特征值分别记为电磁激励特征值；将多组在线检测的电磁激励特征值作为输入值带入BP神经网络模型得到当前带钢的屈服强度。The invention installs the eddy current probe on one side of the moving strip, uses the detection plate to excite the eddy current probe with multiple groups of different frequencies, and returns the detected eigenvalue changes of the real part and the imaginary part of the eddy current probe at regular intervals. The eigenvalues of the part and the imaginary part are respectively recorded as the eigenvalues of the electromagnetic excitation; the eigenvalues of the electromagnetic excitation detected by multiple groups of online detection are taken as input values and brought into the BP neural network model to obtain the yield strength of the current strip.
进一步改进，所述的BP神经网络模型将冷轧薄带钢屈服延伸率与多个检测频率的涡流检测特征值对应，通过输入当前带钢厚度参数来控制变量，建立BP神经网络数学模型。Further improvement, the BP neural network model corresponds the yield elongation of cold-rolled thin strip steel to the eddy current detection characteristic values of multiple detection frequencies, and the BP neural network mathematical model is established by inputting the current strip thickness parameters to control the variables.
进一步改进，所述的电磁激励特征值选择4个频率作为多频涡流的检测频率，使用四个频率点下所检测到的4个实部特征值和4个虚部特征值作为电磁激励特征值，每个频率的每个特征值输出为一个曲线信号，每一个曲线信号通过定义来转换为一个特征值参数。Further improvement, the electromagnetic excitation eigenvalue selects 4 frequencies as the detection frequency of the multi-frequency eddy current, and uses the 4 real part eigenvalues and 4 imaginary part eigenvalues detected under the four frequency points as the electromagnetic excitation eigenvalues , each eigenvalue of each frequency is output as a curve signal, and each curve signal is converted into an eigenvalue parameter by definition.
进一步改进，所述的电磁激励特征值包括15Khz激励频率下测得的涡流实部和虚部特征值，30Khz频率下测得的涡流实部和虚部特征值，60Khz频率下测得的涡流实部和虚部特征值，95Khz频率下测得的涡流实部和虚部特征值。Further improvement, the electromagnetic excitation eigenvalues include the real and imaginary eigenvalues of the eddy current measured at an excitation frequency of 15Khz, the real and imaginary eigenvalues of the eddy current measured at a frequency of 30Khz, and the real and imaginary eigenvalues of the eddy current measured at a frequency of 60Khz. Part and imaginary eigenvalues, real and imaginary part eigenvalues of the eddy current measured at 95Khz frequency.
进一步改进，在带钢屈服强度检测的过程中，涡流探头与带钢之间的距离，即提离，随时间无序变化，通过多个特征值中对屈服强度不敏感而对提离较为敏感的特征值，来对当前提离值进行预测，并反馈到系统中来对预测结果进行补偿。本发明在移动中的带钢一侧安装涡流探头，利用检测板对涡流探头进行多组不同频率的激励，并定时返回检测到的涡流探头实部和虚部的特征值变化，将涡流探头实部和虚部的特征值分别记为电磁激励特征值；将多组在线检测的电磁激励特征值作为输入值带入BP神经网络模型得到当前带钢的屈服强度。Further improvement, in the process of testing the yield strength of the strip, the distance between the eddy current probe and the strip, that is, the lift-off, changes disorderly with time, and is not sensitive to the yield strength but more sensitive to the lift-off through multiple eigenvalues. , to predict the current lift-off value, and feed it back to the system to compensate the prediction result. The invention installs the eddy current probe on one side of the moving strip, uses the detection plate to excite the eddy current probe with multiple groups of different frequencies, and returns the detected eigenvalue changes of the real part and the imaginary part of the eddy current probe at regular intervals. The eigenvalues of the part and the imaginary part are respectively recorded as the eigenvalues of the electromagnetic excitation; the eigenvalues of the electromagnetic excitation detected by multiple groups of online detection are taken as input values and brought into the BP neural network model to obtain the yield strength of the current strip.
进一步改进，所述的BP神经网络模型将冷轧薄带钢屈服延伸率与多个检测频率的涡流检测特征值对应，通过输入当前带钢厚度参数来控制变量，建立BP神经网络数学模型。Further improvement, the BP neural network model corresponds the yield elongation of cold-rolled thin strip steel to the eddy current detection characteristic values of multiple detection frequencies, and the BP neural network mathematical model is established by inputting the current strip thickness parameters to control the variables.
进一步改进，所述的电磁激励特征值选择4个频率作为多频涡流的检测频率，使用四个频率点下所检测到的4个实部特征值和4个虚部特征值作为电磁激励特征值，每个频率的每个特征值输出为一个曲线信号，每一个曲线信号通过定义来转换为一个特征值参数。Further improvement, the electromagnetic excitation eigenvalue selects 4 frequencies as the detection frequency of the multi-frequency eddy current, and uses the 4 real part eigenvalues and 4 imaginary part eigenvalues detected under the four frequency points as the electromagnetic excitation eigenvalues , each eigenvalue of each frequency is output as a curve signal, and each curve signal is converted into an eigenvalue parameter by definition.
进一步改进，所述的电磁激励特征值包括15Khz激励频率下测得的涡流实部和虚部特征值，30Khz频率下测得的涡流实部和虚部特征值，60Khz频率下测得的涡流实部和虚部特征值，95Khz频率下测得的涡流实部和虚部特征值。Further improvement, the electromagnetic excitation eigenvalues include the real and imaginary eigenvalues of the eddy current measured at an excitation frequency of 15Khz, the real and imaginary eigenvalues of the eddy current measured at a frequency of 30Khz, and the real and imaginary eigenvalues of the eddy current measured at a frequency of 60Khz. Part and imaginary eigenvalues, real and imaginary part eigenvalues of the eddy current measured at 95Khz frequency.
进一步改进，在带钢屈服强度检测的过程中，涡流探头与带钢之间的距离，即提离，随时间无序变化，通过多个特征值中对屈服强度不敏感而对提离较为敏感的特征值，来对当前提离值进行预测，并反馈到系统中来对预测结果进行补偿。Further improvement, in the process of testing the yield strength of the strip, the distance between the eddy current probe and the strip, that is, the lift-off, changes disorderly with time, and is not sensitive to the yield strength but more sensitive to the lift-off through multiple eigenvalues. , to predict the current lift-off value, and feed it back to the system to compensate the prediction result.
工作原理working principle
涡流检测原理如图2所示。变化着的磁场会在导体中感应出电动势和电流，即电磁感应现象。由楞次定律可知，当穿过线圈的磁通量发生变化时，线圈中的感应电流总是企图使它自身所产生的磁场去阻碍线圈磁通的变化。线圈中感应电动势ε的大小与穿过线圈的磁通量Φ随时间t的变化率成正比，表达式为：The principle of eddy current testing is shown in Figure 2. The changing magnetic field induces electromotive force and current in the conductor, that is, the phenomenon of electromagnetic induction. According to Lenz's law, when the magnetic flux passing through the coil changes, the induced current in the coil always tries to make the magnetic field generated by itself to hinder the change of the magnetic flux of the coil. The magnitude of the induced electromotive force ε in the coil is proportional to the rate of change of the magnetic flux Φ passing through the coil with time t, and the expression is:
式中，ε为感应电动势，单位是V；N为线圈匝数；Φ为穿过线圈的磁通量，单位是Wb；t为时间，单位是s。In the formula, ε is the induced electromotive force, the unit is V; N is the number of turns of the coil; Φ is the magnetic flux passing through the coil, the unit is Wb; t is the time, the unit is s.
涡流检测(EC)以电磁感应理论为基础，主要适用于各种金属材料的检测。涡流检测基本原理如图2所示，当通有交变电流的激励线圈靠近被测物体时，因外部磁场的激励，被测金属试件中感应出涡电流。涡流的幅值、相位等参数均受被测物体影响，而由被测物体中的涡流产生的磁场也将在激励线圈中感应出电压。因此，通过观测检测线圈上感应电压的变化，就得到被测物体上的相关状态信息。Eddy current testing (EC) is based on the theory of electromagnetic induction and is mainly applicable to the testing of various metal materials. The basic principle of eddy current detection is shown in Figure 2. When the excitation coil with alternating current is close to the object to be measured, due to the excitation of the external magnetic field, eddy current is induced in the metal test piece to be tested. The parameters such as the amplitude and phase of the eddy current are affected by the measured object, and the magnetic field generated by the eddy current in the measured object will also induce a voltage in the excitation coil. Therefore, by observing the change of the induced voltage on the detection coil, the relevant state information on the measured object can be obtained.
在涡流检测的过程中，采用线圈作为探头，在与电阻分压的情况下，被测物体中的信息可以通过不同大小的线圈的输出电压变化反映出来，输出的电压值与激励大小，激励频率，线圈参数，提离值与所测物体的状态信息等诸多因素相关In the process of eddy current testing, the coil is used as the probe. In the case of dividing the voltage with the resistance, the information in the measured object can be reflected by the output voltage changes of the coils of different sizes. The output voltage value is related to the excitation size and excitation frequency. , coil parameters, lift-off value are related to the state information of the measured object and many other factors
常规涡流检测采用单个频率的激励信号激励涡流探头来进行检测，由于只有一个激励频率的原因，往往会受到一些与其频率参数相关的难以消除的外在的干扰信号的干扰。多频涡流检测则是使用两个及两个以上的激励频率，对同个或不同个线圈进行激励，通过调节信号幅度、相位和波形等方法，消去一些仅影响单一频率的干扰信号，使检测结果更加准确。Conventional eddy current testing uses a single frequency excitation signal to excite the eddy current probe for detection. Because there is only one excitation frequency, it is often interfered by some external interference signals related to its frequency parameters that are difficult to eliminate. Multi-frequency eddy current detection uses two or more excitation frequencies to excite the same or different coils. By adjusting the signal amplitude, phase and waveform, some interference signals that only affect a single frequency are eliminated, so that the detection The results are more accurate.
在经过了多次实验后，本专利选择了上述4个频率作为多频涡流的检测频率，使用四个频率点下所检测到的4个实部特征值和4个虚部特征值，来对带钢的屈服强度来进行预测。After many experiments, this patent selects the above-mentioned 4 frequencies as the detection frequency of multi-frequency eddy current, and uses 4 real part eigenvalues and 4 imaginary part eigenvalues detected at the four frequency points to detect The yield strength of the strip is predicted.
在多次实验积累实验数据后，使用BP神经网络进行建模。使用matlab中的神经网络工具箱，使用其中的BP神经网络，对积累的实验数据进行建模，以得到神经网络模型用来进行屈服强度的预测。After accumulating experimental data for many experiments, the BP neural network is used for modeling. Using the neural network toolbox in matlab and using the BP neural network in it, the accumulated experimental data are modeled to obtain the neural network model for prediction of yield strength.
在一条生产线上应用了本专利技术，应用到一卷带钢的在线检测。厚度为0.7mm，宽度为1600mm，带钢全长为942m；该检测系统有2453个输出，也即平均0.38米一个测量结果。在检测效果满足上述检测要求的同时，比之现有技术的只能剪切试样来测试，数据量和实时性均大大提升。The patented technology is applied to a production line and applied to the online inspection of a coil of strip steel. The thickness is 0.7mm, the width is 1600mm, and the total length of the strip is 942m; the detection system has 2453 outputs, that is, an average measurement result of 0.38 meters. While the detection effect meets the above detection requirements, compared with the prior art that can only test by cutting the sample, the data volume and real-time performance are greatly improved.
上述方法用于某生产线10卷带钢的屈服延伸率的在线测量，并头尾各取样一样，采用离线拉伸测试的方法获得数值，所得到的结果和在线测量的对应的位置的断后伸长率值比较。在10％的相对误差精度范围内，样本合格率为90％以上。The above method is used for the online measurement of the yield elongation of 10 coils of strip steel in a production line, and the sampling is the same at the head and tail, and the value is obtained by the offline tensile test method. rate comparison. Within 10% relative error accuracy, the sample pass rate is over 90%.
本说明书中的各个实施例均采用递进的方式描述，各个实施例之间相同相似的部分互相参见即可，每个实施例重点说明的都是与其他实施例的不同之处。尤其，对于设备实施例而言，以上所述仅是本发明的优选实施方式，由于其基本相似于方法实施例，所以描述得比较简单，相关之处参见方法实施例的部分说明即可。以上所述，仅为本发明的具体实施方式，但本发明的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本发明揭露的技术范围内，对于本技术领域的普通技术人员来说，可轻易想到的变化或替换，在不脱离本发明原理的前提下，都应涵盖在本发明的保护范围之内。因此，本发明的保护范围应该以权利要求的保护范围为准。Each embodiment in this specification is described in a progressive manner, and the same and similar parts between the various embodiments may be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiments, the above descriptions are only preferred implementations of the present invention. Since they are basically similar to the method embodiments, the description is relatively simple. For relevant details, please refer to the partial descriptions of the method embodiments. The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. In other words, any easily conceivable changes or substitutions should be included within the protection scope of the present invention without departing from the principles of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.
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| CN107520257A (en) * | 2016-06-22 | 2017-12-29 | 上海宝钢工业技术服务有限公司 | Strip mechanical performance on-line detecting system |
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| CN113672867A (en) * | 2021-07-29 | 2021-11-19 | 南京航空航天大学 | Cold-rolled sheet yield and tensile strength on-line detection method based on dimension reduction technology |
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| CN101975543A (en) * | 2010-08-31 | 2011-02-16 | 电子科技大学 | Eddy displacement detection method and device thereof for eliminating electronic shimmy |
| CN107520257A (en) * | 2016-06-22 | 2017-12-29 | 上海宝钢工业技术服务有限公司 | Strip mechanical performance on-line detecting system |
| CN109991308A (en) * | 2019-03-18 | 2019-07-09 | 北京工业大学 | Micromagnetic non-destructive online testing system for comprehensive mechanical properties of thin strip steel |
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