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CN113670722A - A kind of testing method of metal tensile strength performance - Google Patents

A kind of testing method of metal tensile strength performance Download PDF

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Publication number
CN113670722A
CN113670722A CN202110960844.0A CN202110960844A CN113670722A CN 113670722 A CN113670722 A CN 113670722A CN 202110960844 A CN202110960844 A CN 202110960844A CN 113670722 A CN113670722 A CN 113670722A
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China
Prior art keywords
metal
processing unit
tensile strength
image acquisition
acquisition unit
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Pending
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CN202110960844.0A
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Chinese (zh)
Inventor
薛同闯
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Suzhou Zhongke Measurement Technology Co ltd
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Suzhou Zhongke Measurement Technology Co ltd
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Priority to CN202110960844.0A priority Critical patent/CN113670722A/en
Publication of CN113670722A publication Critical patent/CN113670722A/en
Pending legal-status Critical Current

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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02Details
    • G01N3/06Special adaptations of indicating or recording means
    • G01N3/066Special adaptations of indicating or recording means with electrical indicating or recording means
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02Details
    • G01N3/06Special adaptations of indicating or recording means
    • G01N3/068Special adaptations of indicating or recording means with optical indicating or recording means
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0001Type of application of the stress
    • G01N2203/0003Steady
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0001Type of application of the stress
    • G01N2203/0012Constant speed test
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0014Type of force applied
    • G01N2203/0016Tensile or compressive
    • G01N2203/0017Tensile
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0058Kind of property studied
    • G01N2203/006Crack, flaws, fracture or rupture
    • G01N2203/0067Fracture or rupture
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0058Kind of property studied
    • G01N2203/0069Fatigue, creep, strain-stress relations or elastic constants
    • G01N2203/0075Strain-stress relations or elastic constants
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02Details not specific for a particular testing method
    • G01N2203/06Indicating or recording means; Sensing means
    • G01N2203/0617Electrical or magnetic indicating, recording or sensing means
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02Details not specific for a particular testing method
    • G01N2203/06Indicating or recording means; Sensing means
    • G01N2203/0641Indicating or recording means; Sensing means using optical, X-ray, ultraviolet, infrared or similar detectors
    • G01N2203/0647Image analysis
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02Details not specific for a particular testing method
    • G01N2203/06Indicating or recording means; Sensing means
    • G01N2203/067Parameter measured for estimating the property
    • G01N2203/0676Force, weight, load, energy, speed or acceleration

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  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)

Abstract

本发明公开了一种金属抗拉伸强度性能的检测方法,包括图像采集单元,所述图像采集单元能采集金属材料的图像,所述图像采集单元连接处理单元,所述处理单元能根据算法处理图像,所述处理单元还连接有角度传感器和测距传感器,且通过角度传感器和测距传感器,所述处理单元能得出金属材料与图像采集单元的距离和角度,并利用处理单元,得出金属的抗拉伸强度。通过图像采集单元并利用算计进行处理,同时利用角度传感器和测距传感器进行数据的测量,并进行总的计算,得出金属试样的抗拉伸强度,能得到不同材质的测试数据,方便对试样的合格率进行充分的实验,为金属的研发提供有力的后勤保障。The invention discloses a method for detecting the tensile strength performance of metal, comprising an image acquisition unit capable of acquiring images of metal materials, the image acquisition unit being connected to a processing unit, and the processing unit capable of processing according to an algorithm image, the processing unit is also connected with an angle sensor and a ranging sensor, and through the angle sensor and the ranging sensor, the processing unit can obtain the distance and angle between the metal material and the image acquisition unit, and use the processing unit to obtain Tensile strength of metals. Through the image acquisition unit and the calculation process, the angle sensor and the ranging sensor are used to measure the data, and the total calculation is carried out to obtain the tensile strength of the metal sample, and the test data of different materials can be obtained. The qualified rate of the sample is fully tested to provide a strong logistical support for the research and development of metals.

Description

Method for detecting tensile strength performance of metal
Technical Field
The invention relates to the field of metal performance testing, in particular to a method for detecting tensile strength performance of metal.
Background
The metal is very common in daily life, but most of the commonly used metals are alloy materials, and the components in the alloy are different according to actual requirements. In particular, the requirement for high-performance and high-strength metal materials requires the development of metal materials with different properties.
However, for a metal material which is developed daily, the performance of the metal material needs to be detected, particularly, the tensile resistance of the metal needs to be tested, most of the existing testing methods obtain a stress-strain curve, and the performance of the metal is obtained through the stress-strain curve.
Therefore, the inventor of the present invention aims to invent a method for detecting tensile strength of metal in view of the above technical problems.
Disclosure of Invention
In order to overcome the defects, the invention aims to provide a method for detecting the tensile strength performance of metal.
In order to achieve the above purposes, the invention adopts the technical scheme that: the detection method for the tensile strength performance of the metal comprises an image acquisition unit, wherein the image acquisition unit can acquire images of the metal material, the image acquisition unit is connected with a processing unit, the processing unit can process the images according to an algorithm, the processing unit is further connected with an angle sensor and a distance measuring sensor, the processing unit can obtain the distance and the angle between the metal material and the image acquisition unit through the angle sensor and the distance measuring sensor, and the processing unit is utilized to obtain the tensile strength of the metal.
The tensile strength of general metal is that the metal is vertically placed, the angle is measured by an angle sensor, the distance is measured by a distance measuring sensor, and then a trigonometric function is utilized, if the horizontal distance b, the inclination angle theta, the vertical distance a of the workpiece, and a-b tan theta are measured, the vertical distance of the workpiece is obtained, obtaining different a through the change of the angle, calculating the stretching amount of the metal through the a at different moments, evaluating whether the metal is qualified or not through the stretching amount, moreover, the calculation of the stretching amount is high in stage, for example, whether the stretching amount is qualified under a certain tension, but when the stretching amount is qualified under a certain tension and a certain time, long-time monitoring is needed, which is difficult to be completed by manpower, therefore, the image acquisition unit is matched, the digital speckle algorithm is utilized to realize the processing of the image, and the measurement of the tensile strength can be realized by utilizing the position change of the pixel points of the image.
Preferably, the image acquisition unit includes the CCD camera, just the CCD camera sets up on the camera cloud platform, through the shooting angle of CCD camera can be adjusted to the camera cloud platform, the camera cloud platform adopts electronic cloud platform, just the camera cloud platform can be connected with the processing unit, just the processing unit can control the work of camera cloud platform. Namely, the processing unit processes the image according to the algorithm, and when the image is not clear or partially not clear, the camera pan-tilt is timely adjusted to obtain clear patterns, and the image is analyzed.
Preferably, the algorithm is a digital speckle algorithm, the processing unit can divide and select the sub-region with the speckle characteristics on the image, compare the sub-region with other images, and obtain displacement values of the sub-region with the speckle characteristics at different times by using the digital speckle algorithm to obtain displacement information of the surface of the workpiece. The method comprises the steps of selecting a sub-area through a spot (characteristic point), simultaneously identifying other images to obtain information of the characteristic point in the images in different time periods, and calculating a displacement value through pixel displacement, an angle obtained by an angle sensor and data obtained by a distance measuring sensor to obtain the performance of the metal material in a stretching state.
Preferably, the processing unit is further connected with a computer, displays the information through a display screen, and inputs the information through a mouse and a keyboard. The visualization degree of the detection system is increased, and the tester can conveniently export data according to the measured data.
Preferably, the metal material is arranged through a support, the support is arranged on a machine table, the metal material is clamped on the support, a tension machine is further arranged on the machine table, and the tension machine can apply tension to the metal material. The force given to the metal sample by the tension machine can be gradually increased or constant, if the force is gradually changed, the maximum stress during fracture can be clearly obtained along with the change of the tension, and the frame number of the CCD camera can be controlled at the moment of fracture to obtain a clearer fracture picture; however, if the metal sample is constant and the constant force acts on the metal sample, the deformation of the metal sample is gradual and slow, and the metal sample cannot be observed by people for a long time.
Preferably, the distance measuring sensor is one of a laser distance measuring sensor and an ultrasonic distance measuring sensor.
The method for detecting the tensile strength performance of the metal has the advantages that the image acquisition unit is used for processing by using a calculator, the angle sensor and the distance measuring sensor are used for measuring data, the total calculation is carried out, the tensile strength of the metal sample is obtained, test data of different materials can be obtained, the qualified rate of the sample can be conveniently and fully tested, and powerful logistics guarantee is provided for the research and development of the metal.
Detailed Description
The following detailed description of the preferred embodiments of the present invention is provided to enable those skilled in the art to more readily understand the advantages and features of the present invention, and to clearly and unequivocally define the scope of the present invention.
The method for detecting the tensile strength performance of the metal in the embodiment comprises an image acquisition unit, wherein the image acquisition unit can acquire an image of the metal material, the image acquisition unit is connected with a processing unit, the processing unit can process the image according to an algorithm, the processing unit is further connected with an angle sensor and a distance measuring sensor, the processing unit can obtain the distance and the angle between the metal material and the image acquisition unit through the angle sensor and the distance measuring sensor, and the processing unit is utilized to obtain the tensile strength of the metal.
The tensile strength of general metal is that the metal is vertically placed, the angle is measured by an angle sensor, the distance is measured by a distance measuring sensor, and then a trigonometric function is utilized, if the horizontal distance b, the inclination angle theta, the vertical distance a of the workpiece, and a-b tan theta are measured, the vertical distance of the workpiece is obtained, obtaining different a through the change of the angle, calculating the stretching amount of the metal through the a at different moments, evaluating whether the metal is qualified or not through the stretching amount, moreover, the calculation of the stretching amount is high in stage, for example, whether the stretching amount is qualified under a certain tension, but when the stretching amount is qualified under a certain tension and a certain time, long-time monitoring is needed, which is difficult to be completed by manpower, therefore, the image acquisition unit is matched, the digital speckle algorithm is utilized to realize the processing of the image, and the measurement of the tensile strength can be realized by utilizing the position change of the pixel points of the image.
The image acquisition unit comprises a CCD camera, the CCD camera is arranged on a camera pan-tilt, the shooting angle of the CCD camera can be adjusted through the camera pan-tilt, the camera pan-tilt adopts an electric pan-tilt, the camera pan-tilt can be connected with the processing unit, and the processing unit can control the camera pan-tilt to work. Namely, the processing unit processes the image according to the algorithm, and when the image is not clear or partially not clear, the camera pan-tilt is timely adjusted to obtain clear patterns, and the image is analyzed.
The algorithm is a digital speckle algorithm, the processing unit can divide and select sub-regions with speckle characteristics on the image, compare the sub-regions with the other images, and obtain displacement values of the sub-regions with the speckle characteristics at different times by using the digital speckle algorithm to obtain displacement information of the surface of the workpiece. The method comprises the steps of selecting a sub-area through a spot (characteristic point), simultaneously identifying other images to obtain information of the characteristic point in the images in different time periods, and calculating a displacement value through pixel displacement, an angle obtained by an angle sensor and data obtained by a distance measuring sensor to obtain the performance of the metal material in a stretching state.
The processing unit is also connected with a computer, displays through a display screen, and inputs through a mouse and a keyboard. The visualization degree of the detection system is increased, and the tester can conveniently export data according to the measured data.
The metal material passes through the support setting, and the support setting is on the board to carry out centre gripping metal material on the support, and still set up the pulling force machine on the board, the pulling force machine can exert pulling force to metal material. The force given to the metal sample by the tension machine can be gradually increased or constant, if the force is gradually changed, the maximum stress during fracture can be clearly obtained along with the change of the tension, and the frame number of the CCD camera can be controlled at the moment of fracture to obtain a clearer fracture picture; however, if the metal sample is constant and the constant force acts on the metal sample, the deformation of the metal sample is gradual and slow, and the metal sample cannot be observed by people for a long time.
And a plurality of mark points can be arranged on the bracket. The distance measuring sensor is one of a laser distance measuring sensor and an ultrasonic distance measuring sensor.
The detection method for the tensile strength performance of the metal has the advantages that the detection method is processed through the image acquisition unit and by using the calculator, meanwhile, the angle sensor and the distance measuring sensor are used for measuring data, the total calculation is carried out, the tensile strength of the metal sample is obtained, test data made of different materials can be obtained, sufficient experiments can be conveniently carried out on the qualified rate of the sample, and powerful logistics guarantee is provided for the research and development of the metal.
The test principle is as follows: the image acquisition unit acquires images in real time, evaluates the clearness of the images according to an image clearness algorithm, and utilizes the camera pan-tilt to adjust the angle to obtain clear images, thereby facilitating the calculation of the subsequent digital speckle algorithm.
The angle sensor and the distance measuring sensor can measure an angle theta and a linear distance a between a testing part and a metal sample to be tested, the other right-angle side is b, the bevel side is c, one side and the angle theta are known, the lengths of b and c can be obtained by utilizing a trigonometric function, the length of b changes along with the change of the stretching amount, the stretching strength performance of the metal is finally obtained, meanwhile, images are shot in real time, the change relation of the stretching amount in continuous time can be obtained by utilizing a digital speckle algorithm, the stretching resistance of the metal to be tested is comprehensively obtained, the performance of the metal to be tested can be comprehensively evaluated, and visual data support is provided for the research and development of the metal.
The above embodiments are merely illustrative of the technical concept and features of the present invention, and the present invention is not limited thereto, and any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of the present invention.

Claims (6)

1. A method for detecting the tensile strength performance of metal is characterized by comprising the following steps: the device comprises an image acquisition unit, the image acquisition unit can acquire images of metal materials, the image acquisition unit is connected with a processing unit, the processing unit can process the images according to an algorithm, the processing unit is further connected with an angle sensor and a distance measuring sensor, the processing unit can obtain the distance and the angle between the metal materials and the image acquisition unit through the angle sensor and the distance measuring sensor, and the processing unit is utilized to obtain the tensile strength of the metal.
2. The method for detecting the tensile strength performance of the metal according to claim 1, wherein the method comprises the following steps: the image acquisition unit comprises a CCD camera, the CCD camera is arranged on a camera pan-tilt, the shooting angle of the CCD camera can be adjusted by the camera pan-tilt, the camera pan-tilt adopts an electric pan-tilt, the camera pan-tilt can be connected with the processing unit, and the processing unit can control the camera pan-tilt to work.
3. The method for detecting the tensile strength performance of the metal according to claim 1, wherein the method comprises the following steps: the algorithm is a digital speckle algorithm, the processing unit can divide and select sub-regions with speckle characteristics on the image, compare the sub-regions with the other images, and obtain displacement values of the sub-regions with the speckle characteristics at different times by using the digital speckle algorithm to obtain displacement information of the surface of the workpiece.
4. The method for detecting the tensile strength performance of the metal according to claim 1, wherein the method comprises the following steps: the processing unit is also connected with a computer, displays through a display screen, and inputs through a mouse and a keyboard.
5. The method for detecting the tensile strength performance of the metal according to claim 1, wherein the method comprises the following steps: the metal material passes through the support setting, the support sets up on the board to carry out centre gripping metal material on the support, and still set up the pulling force machine on the board, the pulling force machine can exert pulling force to metal material.
6. The method for detecting the tensile strength performance of the metal according to claim 1, wherein the method comprises the following steps: the distance measuring sensor is one of a laser distance measuring sensor and an ultrasonic distance measuring sensor.
CN202110960844.0A 2021-08-20 2021-08-20 A kind of testing method of metal tensile strength performance Pending CN113670722A (en)

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Cited By (1)

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Application publication date: 20211119