CN113866261B - Steel plate defect measuring device and method - Google Patents
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- 230000007547 defect Effects 0.000 title claims abstract description 69
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Abstract
本发明涉及一种钢板缺陷测量装置及方法，其中装置包括：永磁铁、屏蔽罩、螺旋线圈、第一圆柱线圈、第二圆柱线圈和检测模块；本发明以钢板为研究对象，建立了带有屏蔽罩、螺旋线圈、第一圆柱线圈、第二圆柱线圈的测量装置，通过分时复用的电磁超声与远场涡流复合检测的测量装置，分析了电磁超声波检测的盲区，优化了复合远场模型的参数，从而扩大了涡流部分检测的范围，很好的弥补了电磁超声检测的盲区。
The invention relates to a steel plate defect measuring device and method, wherein the device includes: a permanent magnet, a shielding cover, a spiral coil, a first cylindrical coil, a second cylindrical coil and a detection module; the invention takes steel plates as the research object and establishes a system with The measurement device of the shield, spiral coil, first cylindrical coil, and second cylindrical coil uses time-division multiplexed electromagnetic ultrasonic and far-field eddy current composite detection measurement devices to analyze the blind spots of electromagnetic ultrasonic detection and optimize the composite far field The parameters of the model thus expand the range of eddy current detection and make up for the blind spot of electromagnetic ultrasonic detection.
Description
技术领域Technical field
本发明涉及钢板质量检测技术领域，特别是涉及一种钢板缺陷测量装置及方法。The present invention relates to the technical field of steel plate quality detection, and in particular to a steel plate defect measuring device and method.
背景技术Background technique
近年来，企业对于钢板质量的要求越来越高，能够及时发现热轧钢板中存在的缺陷并及时调整工艺参数是提高钢板质量的前提。在缺陷检测的实际需求中，单一的检测方法难以满足对试件缺陷进行大范围、迅速、精确的判断和分析。电磁超声检测方法可以很好的解决热轧钢板内部缺陷的检测问题，但是由于回波信号与发射波的叠加造成对钢板表面的缺陷检测的盲区；电涡流检测方法对于表面及近表面的缺陷可以达到高精度的检测，但是由于趋肤深度的限制，无法对深埋部位缺陷进行有效检测。In recent years, enterprises have increasingly higher requirements for the quality of steel plates. Being able to promptly discover defects in hot-rolled steel plates and adjust process parameters in a timely manner is a prerequisite for improving the quality of steel plates. In the actual demand for defect detection, a single detection method cannot satisfy the large-scale, rapid and accurate judgment and analysis of test piece defects. The electromagnetic ultrasonic testing method can well solve the problem of detecting internal defects of hot-rolled steel plates, but the superposition of echo signals and emitted waves causes a blind spot in the detection of defects on the surface of the steel plate; the eddy current testing method can detect defects on the surface and near the surface. High-precision detection is achieved, but due to the limitation of skin depth, defects in deeply buried parts cannot be effectively detected.
发明内容Contents of the invention
为了克服现有技术的不足，本发明的目的是提供一种钢板缺陷测量装置及方法。In order to overcome the shortcomings of the prior art, the object of the present invention is to provide a steel plate defect measuring device and method.
为实现上述目的，本发明提供了如下方案：In order to achieve the above objects, the present invention provides the following solutions:
一种钢板缺陷测量装置，包括：永磁铁、屏蔽罩、螺旋线圈、第一圆柱线圈、第二圆柱线圈和检测模块；A steel plate defect measuring device, including: a permanent magnet, a shielding cover, a spiral coil, a first cylindrical coil, a second cylindrical coil and a detection module;
所述永磁铁和所述螺旋线圈设置在所述屏蔽罩内，所述螺旋线圈用于激励所述永磁铁产生具有缺陷信息的检测信号；所述检测信号包括磁信号和涡流信号；所述第一圆柱线圈和第二圆柱线圈均设置在屏蔽罩外，所述第一圆柱线圈设置在所述第二圆柱线圈和所述屏蔽罩之间；所述第一圆柱线圈和所述第二圆柱线圈用于接收所述检测信号；所述检测模块分别与所述第一圆柱线圈和所述第二圆柱线圈连接，用于检测所述第一圆柱线圈和所述第二圆柱线圈的变化参数，并根据所述变化参数得到缺陷信息。The permanent magnet and the spiral coil are arranged in the shielding case, and the spiral coil is used to excite the permanent magnet to generate a detection signal with defect information; the detection signal includes a magnetic signal and an eddy current signal; the third A cylindrical coil and a second cylindrical coil are both arranged outside the shielding case, and the first cylindrical coil is arranged between the second cylindrical coil and the shielding case; the first cylindrical coil and the second cylindrical coil used to receive the detection signal; the detection module is connected to the first cylindrical coil and the second cylindrical coil respectively, and is used to detect the changing parameters of the first cylindrical coil and the second cylindrical coil, and Defect information is obtained according to the changing parameters.
优选地，所述螺旋线圈的激励频率为400HZ。Preferably, the excitation frequency of the spiral coil is 400HZ.
优选地，所述第一圆柱线圈和所述第二圆柱线圈之间的间距为28mm。Preferably, the distance between the first cylindrical coil and the second cylindrical coil is 28 mm.
优选地，所述第一圆柱线圈的高度和/或所述第二圆柱线圈的高度为所述第一圆柱线圈的外径长度和/或所述第二圆柱线圈的外径长度的6倍。Preferably, the height of the first cylindrical coil and/or the height of the second cylindrical coil is 6 times the outer diameter length of the first cylindrical coil and/or the outer diameter length of the second cylindrical coil.
优选地，所述第一圆柱线圈和/或所述第二圆柱线圈的线圈匝数为1000。Preferably, the number of coil turns of the first cylindrical coil and/or the second cylindrical coil is 1000.
优选地，所述磁信号和涡流信号共同作用的区域范围为5mm至15mm。Preferably, the area in which the magnetic signal and the eddy current signal interact together ranges from 5mm to 15mm.
优选地，所述检测模块包括：Preferably, the detection module includes:
获取单元，分别与所述第一圆柱线圈和所述第二圆柱线圈连接，用于获取所述第一圆柱线圈和所述第二圆柱线圈的变化参数；所述变化参数包括电压变化参数或阻抗变化参数；An acquisition unit is connected to the first cylindrical coil and the second cylindrical coil respectively, and is used to acquire the changing parameters of the first cylindrical coil and the second cylindrical coil; the changing parameters include voltage changing parameters or impedance. change parameters;
融合单元，与所述获取单元连接，用于基于向量机模型对所述第一圆柱线圈和所述第二圆柱线圈的变化参数进行融合，得到融合信息；a fusion unit, connected to the acquisition unit, used to fuse the changing parameters of the first cylindrical coil and the second cylindrical coil based on a vector machine model to obtain fusion information;
分析单元，与所述融合单元连接，用于根据所述融合信息进行分析，得到所述缺陷信息。An analysis unit is connected to the fusion unit and used to analyze according to the fusion information to obtain the defect information.
优选地，所述向量机模型是根据灰狼算法优化后得到的。Preferably, the vector machine model is optimized according to the gray wolf algorithm.
一种钢板缺陷测量方法，应用于上述钢板缺陷测量装置，所述钢板缺陷测量方法包括：A steel plate defect measurement method, applied to the above-mentioned steel plate defect measurement device, the steel plate defect measurement method includes:
利用螺旋线圈激励永磁铁产生具有缺陷信息的检测信号；所述检测信号包括磁信号和涡流信号；The spiral coil is used to excite the permanent magnet to generate a detection signal with defect information; the detection signal includes a magnetic signal and an eddy current signal;
利用第一圆柱线圈和第二圆柱线圈接收所述检测信号；所述检测信号分别作用于所述第一圆柱线圈和所述第二圆柱线圈，以使所述第一圆柱线圈和所述第二圆柱线圈产生参数变化；The first cylindrical coil and the second cylindrical coil are used to receive the detection signal; the detection signal acts on the first cylindrical coil and the second cylindrical coil respectively, so that the first cylindrical coil and the second cylindrical coil Cylindrical coils produce parameter changes;
检测所述第一圆柱线圈和所述第二圆柱线圈的变化参数，并根据所述变化参数得到缺陷信息。The changing parameters of the first cylindrical coil and the second cylindrical coil are detected, and defect information is obtained according to the changing parameters.
优选地，所述检测所述第一圆柱线圈和所述第二圆柱线圈的变化参数，并根据所述变化参数得到缺陷信息，包括：Preferably, the step of detecting changing parameters of the first cylindrical coil and the second cylindrical coil and obtaining defect information based on the changing parameters includes:
获取所述第一圆柱线圈和所述第二圆柱线圈的变化参数；所述变化参数包括电压变化参数或阻抗变化参数；Obtain the changing parameters of the first cylindrical coil and the second cylindrical coil; the changing parameters include voltage changing parameters or impedance changing parameters;
基于向量机模型对所述第一圆柱线圈和所述第二圆柱线圈的变化参数进行融合，得到融合信息；Fusion of changing parameters of the first cylindrical coil and the second cylindrical coil based on a vector machine model to obtain fusion information;
根据所述融合信息进行分析，得到所述缺陷信息。Analyze according to the fusion information to obtain the defect information.
根据本发明提供的具体实施例，本发明公开了以下技术效果：According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:
本发明提供了一种钢板缺陷测量装置及方法，其中装置包括：永磁铁、屏蔽罩、螺旋线圈、第一圆柱线圈、第二圆柱线圈和检测模块；所述永磁铁和所述螺旋线圈设置在所述屏蔽罩内，所述螺旋线圈用于激励所述永磁铁产生具有缺陷信息的检测信号；所述检测信号包括磁信号和涡流信号；所述第一圆柱线圈和第二圆柱线圈均设置在屏蔽罩外，所述第一圆柱线圈设置在所述第二圆柱线圈和所述屏蔽罩之间；所述第一圆柱线圈和所述第二圆柱线圈用于接收所述检测信号；所述检测模块分别与所述第一圆柱线圈和所述第二圆柱线圈连接，用于检测所述第一圆柱线圈和所述第二圆柱线圈的变化参数，并根据所述变化参数得到缺陷信息。在具体实施例中，本发明以钢板为研究对象，建立了带有屏蔽罩、螺旋线圈、第一圆柱线圈、第二圆柱线圈的测量装置，通过分时复用的电磁超声与远场涡流复合检测的测量装置，分析了电磁超声波检测的盲区，优化了复合远场模型的参数，从而扩大了涡流部分检测的范围，很好的弥补了电磁超声检测的盲区。The invention provides a steel plate defect measuring device and method, wherein the device includes: a permanent magnet, a shielding cover, a spiral coil, a first cylindrical coil, a second cylindrical coil and a detection module; the permanent magnet and the spiral coil are arranged on In the shielding case, the spiral coil is used to excite the permanent magnet to generate a detection signal with defect information; the detection signal includes a magnetic signal and an eddy current signal; the first cylindrical coil and the second cylindrical coil are both arranged in Outside the shielding case, the first cylindrical coil is arranged between the second cylindrical coil and the shielding case; the first cylindrical coil and the second cylindrical coil are used to receive the detection signal; the detection The module is connected to the first cylindrical coil and the second cylindrical coil respectively, and is used to detect changing parameters of the first cylindrical coil and the second cylindrical coil, and obtain defect information according to the changing parameters. In a specific embodiment, the present invention takes steel plates as the research object, and establishes a measuring device with a shield, a spiral coil, a first cylindrical coil, and a second cylindrical coil, and combines time-division multiplexing of electromagnetic ultrasound and far-field eddy currents. The detection measuring device analyzes the blind area of electromagnetic ultrasonic detection and optimizes the parameters of the composite far-field model, thus expanding the range of eddy current detection and making up for the blind area of electromagnetic ultrasonic detection.
附图说明Description of the drawings
为了更清楚地说明本发明实施例或现有技术中的技术方案，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性的前提下，还可以根据这些附图获得其他的附图。In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some of the drawings of the present invention. Embodiments, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without exerting creative efforts.
图1为本发明提供的实施例中的电磁超声与涡流复合结构的示意图；Figure 1 is a schematic diagram of an electromagnetic ultrasound and eddy current composite structure in an embodiment provided by the present invention;
图2为本发明提供的实施例中的钢板缺陷测量方法的流程图。Figure 2 is a flow chart of a steel plate defect measurement method in an embodiment provided by the present invention.
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他实施例，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 some of the embodiments of the present invention, rather than all 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 fall within the scope of protection of the present invention.
本发明的目的是提供一种钢板缺陷测量装置及方法，能够扩大了涡流部分检测的范围，很好的弥补了电磁超声检测的盲区。The purpose of the present invention is to provide a steel plate defect measuring device and method, which can expand the range of eddy current partial detection and well make up for the blind area of electromagnetic ultrasonic detection.
为使本发明的上述目的、特征和优点能够更加明显易懂，下面结合附图和具体实施方式对本发明作进一步详细的说明。In order to make the above objects, features and advantages of the present invention more obvious and understandable, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.
图1为本发明提供的实施例中的电磁超声与涡流复合结构的示意图，如图1所示，本发明提供了一种钢板缺陷测量装置，包括：永磁铁、屏蔽罩、螺旋线圈、第一圆柱线圈、第二圆柱线圈和检测模块。Figure 1 is a schematic diagram of the electromagnetic ultrasonic and eddy current composite structure in an embodiment of the present invention. As shown in Figure 1, the present invention provides a steel plate defect measuring device, including: a permanent magnet, a shielding cover, a spiral coil, a first Cylindrical coil, second cylindrical coil and detection module.
所述永磁铁(图中为氧化铁屏蔽罩)和所述螺旋线圈设置在所述屏蔽罩(屏蔽罩内存在有空气)内，所述螺旋线圈用于激励所述永磁铁(图中N和S代表永磁铁的两极)产生具有缺陷信息的检测信号；所述检测信号包括磁信号和涡流信号；所述第一圆柱线圈和第二圆柱线圈(图中为圆柱线圈)均设置在屏蔽罩外，所述第一圆柱线圈设置在所述第二圆柱线圈和所述屏蔽罩之间；所述第一圆柱线圈和所述第二圆柱线圈用于接收所述检测信号；所述检测模块分别与所述第一圆柱线圈和所述第二圆柱线圈连接，用于检测所述第一圆柱线圈和所述第二圆柱线圈的变化参数，并根据所述变化参数得到缺陷信息。The permanent magnet (iron oxide shield in the figure) and the spiral coil are arranged in the shield (air exists in the shield), and the spiral coil is used to excite the permanent magnet (N and N in the figure) S represents the two poles of the permanent magnet) to generate a detection signal with defect information; the detection signal includes a magnetic signal and an eddy current signal; the first cylindrical coil and the second cylindrical coil (cylindrical coil in the figure) are both arranged outside the shielding cover , the first cylindrical coil is arranged between the second cylindrical coil and the shielding cover; the first cylindrical coil and the second cylindrical coil are used to receive the detection signal; the detection module is respectively connected with The first cylindrical coil and the second cylindrical coil are connected for detecting changing parameters of the first cylindrical coil and the second cylindrical coil, and obtaining defect information according to the changing parameters.
进一步地，所述第一圆柱线圈处于图1中的近场位置处；所述第二圆柱线圈处于图1中的远场位置处。Further, the first cylindrical coil is at a near-field position in Figure 1; the second cylindrical coil is at a far-field position in Figure 1.
可选地，所述螺旋线圈设置在所述永磁铁和钢板之间。所述螺旋线圈可以设置为多组。本实施例中所述螺旋线圈为两组，分别设置在了所述永磁铁底部的两侧。Optionally, the spiral coil is disposed between the permanent magnet and the steel plate. The spiral coils may be arranged in multiple groups. In this embodiment, the spiral coils are two groups, which are respectively arranged on both sides of the bottom of the permanent magnet.
具体的，所述钢板的型号为Q235。Specifically, the model of the steel plate is Q235.
进一步地，远场涡流一般由激励线圈和检测线圈组(第一圆柱线圈和第二圆柱线圈)，为了较好的产生远场涡流现象，需要用磁屏蔽结构来减少两个线圈之间的直接耦合磁通路，增大间接耦合磁通路，使得磁能量能够二次穿过被测物，将带有缺陷信息的磁信号和涡流信号从激励线圈传递到检测线圈，同时还需要选择合适的参数：激发线圈的频率、两个线圈之间的间距，合适的磁屏蔽结构以及线圈的匝数。Furthermore, far-field eddy currents are generally composed of an excitation coil and a detection coil group (the first cylindrical coil and the second cylindrical coil). In order to better produce the far-field eddy current phenomenon, a magnetic shielding structure is needed to reduce the direct connection between the two coils. The coupling magnetic path increases the indirect coupling magnetic path, so that the magnetic energy can pass through the object under test twice, and the magnetic signal and eddy current signal with defect information are transmitted from the excitation coil to the detection coil. At the same time, appropriate parameters need to be selected: The frequency of the excitation coil, the spacing between the two coils, suitable magnetic shielding structure and the number of turns of the coil.
优选地，所述螺旋线圈的激励频率为400HZ。Preferably, the excitation frequency of the spiral coil is 400HZ.
优选地，所述第一圆柱线圈和所述第二圆柱线圈之间的间距为28mm。Preferably, the distance between the first cylindrical coil and the second cylindrical coil is 28 mm.
具体的，所述屏蔽罩的材质为氧化铁。Specifically, the shielding cover is made of iron oxide.
优选地，所述第一圆柱线圈的高度和/或所述第二圆柱线圈的高度为所述第一圆柱线圈的外径长度和/或所述第二圆柱线圈的外径长度的6倍。Preferably, the height of the first cylindrical coil and/or the height of the second cylindrical coil is 6 times the outer diameter length of the first cylindrical coil and/or the outer diameter length of the second cylindrical coil.
优选地，所述第一圆柱线圈和/或所述第二圆柱线圈的线圈匝数为1000。Preferably, the number of coil turns of the first cylindrical coil and/or the second cylindrical coil is 1000.
优选地，所述磁信号和涡流信号共同作用的区域范围为5mm至15mm。Preferably, the area in which the magnetic signal and the eddy current signal interact together ranges from 5mm to 15mm.
本实施例在仿真过程中，电磁超声激励信号的作用时间为10μs，电磁超声波在钢板中的波速为3000m/s左右，当缺陷位于15mm以内时，含有缺陷信息的回波，会与发射波混叠，也即电磁超声波的检测盲区为15mm以内。而15mm以内的缺陷信息，可以用电涡流检测方法检出。目前所报道的电磁超声/涡流复合检测所使用的涡流激励频率范围为100k—10MHz，Q235钢板的电导率为，由涡流激励信号在100KHz下，渗透深度为不足1mm，超过1mm，对缺陷的检测精度不高。During the simulation process of this embodiment, the action time of the electromagnetic ultrasonic excitation signal is 10 μs, and the wave speed of the electromagnetic ultrasonic wave in the steel plate is about 3000m/s. When the defect is within 15mm, the echo containing the defect information will mix with the transmitted wave. Overlap, that is, the detection blind zone of electromagnetic ultrasonic waves is within 15mm. Defect information within 15mm can be detected using eddy current testing. The eddy current excitation frequency range used in the currently reported electromagnetic ultrasonic/eddy current composite testing is 100k-10MHz. The conductivity of the Q235 steel plate is based on the eddy current excitation signal at 100KHz. The penetration depth is less than 1mm and exceeds 1mm. The detection of defects The accuracy is not high.
由于远场涡流激励信号的频率在10Hz—1000Hz，频率越低涡流渗透越深，所以远场涡流可以检测到15mm深的缺陷，同时对于5mm-15mm缺陷的检测精度比常规涡流的检测精度高，电磁超声与远场涡流数据融合所反演的缺陷参数，也较为准确。Since the frequency of the far-field eddy current excitation signal is between 10Hz and 1000Hz, the lower the frequency, the deeper the eddy current penetrates. Therefore, the far-field eddy current can detect defects up to 15mm deep. At the same time, the detection accuracy for 5mm-15mm defects is higher than that of conventional eddy current. The defect parameters inverted by the fusion of electromagnetic ultrasound and far-field eddy current data are also relatively accurate.
低频信号下，铁氧体(屏蔽罩)对磁场有屏蔽作用，可以屏蔽空气中的磁场，使得在相同激励信号下，涡流深度增大。按照如图1所示，两种复合结构分别搭建近场涡流复合模型和远场涡流复合模型，都施加400Hz的激励信号，对15mm和13mm处缺陷进行检测。Under low-frequency signals, the ferrite (shielding cover) has a shielding effect on the magnetic field and can shield the magnetic field in the air, making the eddy current depth increase under the same excitation signal. As shown in Figure 1, the near-field eddy current composite model and the far-field eddy current composite model were built for the two composite structures respectively, and a 400Hz excitation signal was applied to detect defects at 15mm and 13mm.
测得远场复合模型的电压差值为5mV，而近场涡流复合模型的电压差值为0mV，检测不到缺陷的变化。这是因为当两个线圈处于合适的距离并且在磁屏蔽罩的影响下，产生了远场现象，提高了线圈的检测范围。The measured voltage difference of the far-field composite model is 5mV, while the voltage difference of the near-field eddy current composite model is 0mV, and no change in defects can be detected. This is because when the two coils are at a suitable distance and under the influence of the magnetic shield, a far-field phenomenon is generated, which improves the detection range of the coil.
优选地，所述检测模块包括：Preferably, the detection module includes:
获取单元，分别与所述第一圆柱线圈和所述第二圆柱线圈连接，用于获取所述第一圆柱线圈和所述第二圆柱线圈的变化参数；所述变化参数包括电压变化参数或阻抗变化参数；An acquisition unit is connected to the first cylindrical coil and the second cylindrical coil respectively, and is used to acquire the changing parameters of the first cylindrical coil and the second cylindrical coil; the changing parameters include voltage changing parameters or impedance. change parameters;
融合单元，与所述获取单元连接，用于基于向量机模型对所述第一圆柱线圈和所述第二圆柱线圈的变化参数进行融合，得到融合信息；a fusion unit, connected to the acquisition unit, used to fuse the changing parameters of the first cylindrical coil and the second cylindrical coil based on a vector machine model to obtain fusion information;
分析单元，与所述融合单元连接，用于根据所述融合信息进行分析，得到所述缺陷信息。An analysis unit is connected to the fusion unit and used to analyze according to the fusion information to obtain the defect information.
优选地，所述向量机模型是根据灰狼算法优化后得到的。Preferably, the vector machine model is optimized according to the gray wolf algorithm.
本实施例中以Q235钢板为研究对象，建立了带有屏蔽罩的、共用螺旋线圈的、分时复用的电磁超声与远场涡流复合检测模型，分析了电磁超声波检测的盲区，优化了复合远场模型的参数，针对电磁超声与电涡流共同作用的区域：5—15mm，利用灰狼优化算法的支持向量机进行缺陷反演并设计了实验验证得到以下结论：In this embodiment, the Q235 steel plate is used as the research object. A time-division multiplexed electromagnetic ultrasonic and far-field eddy current composite detection model with a shielded cover, a shared spiral coil, and a time-division multiplexing model are established. The blind spots of the electromagnetic ultrasonic detection are analyzed and the composite detection model is optimized. The parameters of the far-field model are aimed at the area where electromagnetic ultrasound and eddy currents interact together: 5-15mm. The support vector machine of the gray wolf optimization algorithm was used to perform defect inversion and experimental verification was designed to obtain the following conclusions:
(1)复合线圈的远场模型的最佳参数为：激励频率为400Hz、线圈间距为28mm，检测线圈的高度为外径的6倍，检测线圈匝数为1000。并且电磁超声结构中的永磁铁不影响远场涡流对缺陷的检测精度。(1) The optimal parameters of the far-field model of the composite coil are: the excitation frequency is 400Hz, the coil spacing is 28mm, the height of the detection coil is 6 times the outer diameter, and the number of turns of the detection coil is 1000. Moreover, the permanent magnets in the electromagnetic ultrasonic structure do not affect the detection accuracy of defects by far-field eddy current.
(2)灰狼算法优化的支持向量机可以将电磁超声和远场涡流信号进行很好的融合，准确率达到了96.14％。(2) The support vector machine optimized by the gray wolf algorithm can well integrate electromagnetic ultrasound and far-field eddy current signals, with an accuracy of 96.14%.
(3)电磁超声与远场涡流复合探头是可行的，远场涡流能够弥补电磁超声检测的短板。(3) A composite probe of electromagnetic ultrasonic and far-field eddy current is feasible, and far-field eddy current can make up for the shortcomings of electromagnetic ultrasonic testing.
具体的，本实施例中基于灰狼优化算法的SVR过程步骤如下：Specifically, the SVR process steps based on the gray wolf optimization algorithm in this embodiment are as follows:
①将做好的混合数据导入Matlab中，并利用Matlab中自带的mapminmax函数将数据归一化到[0,1]区间，完成数据初始化。① Import the prepared mixed data into Matlab, and use the mapminmax function that comes with Matlab to normalize the data to the [0,1] interval to complete the data initialization.
②设置灰狼优化算法的参数：种群规模设置为20，迭代次数设置为50，设置参数c和参数g的取值范围为0.001-100。②Set the parameters of the gray wolf optimization algorithm: set the population size to 20, the number of iterations to 50, and set the value range of parameter c and parameter g to 0.001-100.
③初始化狼群：狼，β狼，δ狼，ω狼(多个)，将参数c和参数g做为狼群的位置。③Initialize the wolf pack: Wolf, β wolf, δ wolf, ω wolf (multiple), use parameter c and parameter g as the position of the wolf pack.
④计算每一个狼的适应度，适应度为最后优化结果的准确率。④ Calculate the fitness of each wolf. The fitness is the accuracy of the final optimization result.
⑤按照适应度的大小对狼群进行排序，顺序为每次把最优的结果放入/>狼的位置信息中。⑤ Sort the wolves according to their fitness, and the order is: Put the best result every time/> The wolf's location information.
⑥根据灰狼算法中，灰狼狩猎、捕猎、包围猎物的数学模型更新每一个狼的位置。⑥Update the position of each wolf according to the mathematical model of gray wolf hunting, hunting, and surrounding prey in the gray wolf algorithm.
⑦求出每一个狼在新位置的适应度.⑦ Find the fitness of each wolf in the new position.
⑧当迭代次数为50次时，狼的位置所包含的c,g即为以RBF为核函数的SVR算法中最优的参数,若迭代次数不够50次，则返回步骤5，继续进行优化。⑧When the number of iterations is 50, The c and g contained in the wolf's position are the optimal parameters in the SVR algorithm with RBF as the kernel function. If the number of iterations is less than 50, return to step 5 and continue optimization.
⑨将得到的最优的c,g输入到算法中，对样本数据进行准确的分类，并输出缺陷的位置和半径。⑨Input the optimal c and g obtained into the algorithm, accurately classify the sample data, and output the location and radius of the defect.
得到的缺陷半径(r)和位置(h)预测集结果如表1所示，表1为缺陷反演结果。The obtained prediction set results of defect radius (r) and position (h) are shown in Table 1. Table 1 shows the defect inversion results.
表1Table 1
如表1所示，反演结果中可以看到，缺陷的反演结果较好，测量结果达到了百分之96.14％。As shown in Table 1, it can be seen from the inversion results that the inversion results of defects are better, and the measurement results reached 96.14%.
图2为本发明提供的实施例中的钢板缺陷测量方法的流程图，如图2所示，本实施例中还提供了一种钢板缺陷测量方法，应用于上述钢板缺陷测量装置，所述钢板缺陷测量方法包括：Figure 2 is a flow chart of a steel plate defect measurement method in an embodiment provided by the present invention. As shown in Figure 2, this embodiment also provides a steel plate defect measurement method, which is applied to the above steel plate defect measurement device. The steel plate Defect measurement methods include:
步骤100：利用螺旋线圈激励永磁铁产生具有缺陷信息的检测信号；所述检测信号包括磁信号和涡流信号。Step 100: Use a spiral coil to excite the permanent magnet to generate a detection signal with defect information; the detection signal includes a magnetic signal and an eddy current signal.
步骤200：利用第一圆柱线圈和第二圆柱线圈接收所述检测信号；所述检测信号分别作用于所述第一圆柱线圈和所述第二圆柱线圈，以使所述第一圆柱线圈和所述第二圆柱线圈产生参数变化。Step 200: Use the first cylindrical coil and the second cylindrical coil to receive the detection signal; the detection signal acts on the first cylindrical coil and the second cylindrical coil respectively, so that the first cylindrical coil and the The second cylindrical coil produces parameter changes.
步骤300：检测所述第一圆柱线圈和所述第二圆柱线圈的变化参数，并根据所述变化参数得到缺陷信息。Step 300: Detect the changing parameters of the first cylindrical coil and the second cylindrical coil, and obtain defect information based on the changing parameters.
优选地，所述检测所述第一圆柱线圈和所述第二圆柱线圈的变化参数，并根据所述变化参数得到缺陷信息，包括：Preferably, the step of detecting changing parameters of the first cylindrical coil and the second cylindrical coil and obtaining defect information based on the changing parameters includes:
获取所述第一圆柱线圈和所述第二圆柱线圈的变化参数；所述变化参数包括电压变化参数或阻抗变化参数。Obtain the changing parameters of the first cylindrical coil and the second cylindrical coil; the changing parameters include voltage changing parameters or impedance changing parameters.
基于向量机模型对所述第一圆柱线圈和所述第二圆柱线圈的变化参数进行融合，得到融合信息。The changing parameters of the first cylindrical coil and the second cylindrical coil are fused based on the vector machine model to obtain fusion information.
根据所述融合信息进行分析，得到所述缺陷信息。Analyze according to the fusion information to obtain the defect information.
本发明的有益效果如下：The beneficial effects of the present invention are as follows:
(1)本发明根据最优参数的设计和优化，使得电磁超声结构中的永磁铁不影响远场涡流对缺陷的检测精度，从而提高了对于钢板缺陷检测的精准程度。(1) The present invention is based on the design and optimization of optimal parameters so that the permanent magnets in the electromagnetic ultrasonic structure do not affect the detection accuracy of defects by far-field eddy currents, thereby improving the accuracy of defect detection in steel plates.
(2)本发明利用灰狼算法优化的支持向量机，可以将电磁超声和远场涡流信号进行很好的融合，提高了检测结果的精确度。(2) The present invention uses the support vector machine optimized by the gray wolf algorithm to well integrate electromagnetic ultrasound and far-field eddy current signals, thereby improving the accuracy of the detection results.
(3)本发明验证了电磁超声与远场涡流复合探头是可行的，远场涡流能够弥补电磁超声检测的短板，从而提供了一种可行的电磁超声与电涡流复合线圈的钢板缺陷测量装置及方法，有效的检测出了钢板在5mm-15mm的缺陷。(3) The present invention has verified that the composite probe of electromagnetic ultrasonic and far-field eddy current is feasible, and the far-field eddy current can make up for the shortcomings of electromagnetic ultrasonic detection, thereby providing a feasible steel plate defect measurement device for electromagnetic ultrasonic and eddy current composite coils. and method, effectively detecting defects in steel plates ranging from 5mm to 15mm.
本说明书中各个实施例采用递进的方式描述，每个实施例重点说明的都是与其他实施例的不同之处，各个实施例之间相同相似部分互相参见即可。对于实施例公开的方法而言，由于其与实施例公开的装置相对应，所以描述的比较简单，相关之处参见装置部分说明即可。Each embodiment in this specification is described in a progressive manner. Each embodiment focuses on its differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. As for the method disclosed in the embodiment, since it corresponds to the device disclosed in the embodiment, the description is relatively simple. For relevant details, please refer to the description of the device.
本文中应用了具体个例对本发明的原理及实施方式进行了阐述，以上实施例的说明只是用于帮助理解本发明的方法及其核心思想；同时，对于本领域的一般技术人员，依据本发明的思想，在具体实施方式及应用范围上均会有改变之处。综上所述，本说明书内容不应理解为对本发明的限制。This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and the core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the present invention There will be changes in the specific implementation methods and application scope of the ideas. In summary, the contents of this description should not be construed as limitations of the present invention.
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