Nondestructive testing method for surface quality of amorphous alloy and application of nondestructive testing method
The electron work function of the surface of amorphous alloy is measured by Kelvin probe microscope, and combined with the observation of atomic force microscope, the problem of low surface quality detection efficiency of amorphous alloys is solved, and fast and accurate non-destructive detection is achieved, which is suitable for online monitoring of amorphous alloys.
Patent Information
- Application Number
- CN202510423842.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-07
- Publication Date
- 2025-07-18
AI Technical Summary
The prior art is difficult to quickly and effectively detect the surface quality of amorphous alloys, especially minor defects, which affects its performance and service life.
Kelvin probe microscope is used to measure the electron work function on the surface of amorphous alloy. By detecting the electron work function when the shear band failure occurs on the surface of amorphous alloy for the first time, non-destructive detection is achieved by observing with atomic force microscope.
It realizes rapid and accurate detection of the surface quality of amorphous alloys, can predict failure behavior, improve detection efficiency and accuracy, and is suitable for online monitoring of amorphous alloys.
Smart Images
Figure CN120334027A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of nondestructive testing of materials, and in particular to a method for nondestructive testing of surface quality based on in-situ detection of electron work function on the surface of an amorphous alloy and its application. Background Art
[0002] Non-destructive testing (NDT) technology usually refers to the use of physical fields (such as sound, light, electricity, magnetism, heat, etc.) and the principle of interaction between materials to qualitatively or quantitatively analyze the internal and surface defects (such as cracks, pores, inclusions, etc.), geometric features (such as thickness, coating) or performance degradation (such as corrosion, fatigue, stress distribution) of materials or structures without damaging or changing the physical and chemical properties of the object being tested. This technology uses the changes in the response to heat, sound, light, electricity, magnetism, etc. caused by the abnormality or defects in the internal and surface structure of the material to obtain information such as the internal structure, properties, and state of the object being tested through advanced testing instruments and equipment, thereby achieving non-destructive qualitative and quantitative analysis of defects, as well as evaluation of product quality and performance. Its core goal is to ensure the safety, reliability and service life of industrial equipment, while avoiding the waste of resources caused by traditional destructive testing. At present, NDT technology is widely used in many fields such as industrial production, quality control, safety assessment, equipment maintenance, etc., and plays an indispensable and important role in ensuring product quality, improving production efficiency, ensuring public safety, and promoting the development of materials science.
[0003] Amorphous alloys are new metal materials obtained by suppressing the orderly arrangement of alloy melt atoms through rapid solidification technology. Due to the unique short-range ordered and long-range disordered atomic stacking characteristics and metal valence bonds, amorphous alloys exhibit a series of excellent physical and chemical properties, such as high strength, high toughness, high elasticity, corrosion resistance, radiation resistance and other excellent characteristics, and play an increasingly important role in high-tech fields such as new energy, electronic power, environmental protection and energy saving, aerospace, and national defense. Although amorphous alloys have excellent physical and chemical properties, they are highly sensitive to various internal and surface defects. In particular, the surface quality of amorphous alloys, such as surface roughness, surface microcracks, and fatigue cracks, will greatly affect their performance and service life during use. However, the current technologies based on surface roughness detection and high-energy X-ray layered scanning are all oriented to crystalline alloy materials, and due to the shortcomings of low equipment resolution, low sensitivity to tiny surface defect detection, and high cost, it is difficult to quickly and effectively detect the surface quality of amorphous alloys. Therefore, a rapid and non-destructive detection technology for the surface quality of amorphous alloys is crucial to promote its practical application.
[0004] The electronic work function, in terms of its physical definition, refers to the minimum energy required to move an electron from inside a solid (near the Fermi level) to a vacuum at absolute zero (0 K), which reflects the binding ability of the material surface to electrons: the larger the value of the electronic work function, the more difficult it is for electrons to escape from the material surface. Therefore, the electronic work function of the material surface can quickly and intuitively reflect the changes in its surface quality. If there are defects, impurities, or different phase structures, it will cause obvious changes in the electronic work function. The Kelvin probe force microscopy (KPFM) is a high-resolution surface electrical characterization technique developed based on the atomic force microscopy (AFM). Its working principle is to utilize the electrostatic interaction between a vibrating conductive probe and the sample surface. By applying a variable bias voltage between the probe and the sample, when the difference between the bias voltage and the difference between the electronic work function of the sample surface and the electronic work function of the probe reaches equilibrium, the electrostatic force between the probe and the sample surface is zero. At this time, the recorded bias voltage is the Kelvin voltage, and this voltage value directly reflects the electronic work function of the sample surface. At the same time, different from traditional crystalline alloys with structural defects such as dislocations and grain boundaries, amorphous alloys do not have the above-mentioned structural defects. Therefore, the surface electronic work function can one-to-one reflect the changes in surface quality. Based on this, we propose a non-destructive testing method for the surface quality of amorphous alloys by detecting the surface electronic work function with a Kelvin probe microscope, especially for the real-time detection of the performance evolution of amorphous alloys during use, and then the occurrence of failure behavior can be effectively predicted. Summary of the Invention
[0005] The present invention provides a non-destructive testing method for the surface quality of amorphous alloys and its application.
[0006] [1] A non-destructive testing method for the surface quality of amorphous alloys, comprising:
[0007] Cyclically testing the amorphous alloy with a sound surface under service conditions until shear band failure first appears on the surface of the amorphous alloy, and detecting the surface electronic work function of the amorphous alloy at this time
[0008] Detecting the surface electronic work function of the amorphous alloy to be tested with the same composition If It is considered that the surface quality of the amorphous alloy to be tested is good, otherwise it is considered that shear band failure has occurred on the surface of the amorphous alloy to be tested.
[0009] In the prior art, the occurrence of shear band failure on the surface of amorphous alloys can be known by AFM observation. Although AFM observation is very intuitive, its field of view is small, and it is time-consuming in actual application. The low detection efficiency when the number of amorphous alloy samples to be tested is large is its shortcoming.
[0010] There is a one-to-one correspondence between the surface electron work function of the amorphous alloy and the surface quality of the amorphous alloy. The surface electron work function of the amorphous alloy decreases as the surface quality of the amorphous alloy deteriorates. Based on this, the present invention proposes a method for reflecting the surface quality of the amorphous alloy by detecting the surface electron work function of the amorphous alloy.
[0011] In the field of amorphous alloys, once shear band failure occurs on the surface of the amorphous alloy, the performance of the amorphous alloy will rapidly deteriorate or even fail as the shear band rapidly expands (and may even turn into cracks). Therefore, the present invention uses the first occurrence of shear band failure on the surface of the amorphous alloy as an indicator to detect the surface electron work function of the amorphous alloy at this time. As a standard, the surface quality, performance status, service life, etc. of the amorphous alloy to be tested are judged accordingly, with high efficiency and accuracy.
[0012] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], the amorphous alloy is a thin film sample.
[0013] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], the substrate material of the amorphous alloy thin film is a flexible material, which may specifically include polyethylene terephthalate (PET), etc., but is not limited thereto. The purpose of selecting the substrate material is to ensure that the sample has the properties of being smooth, flat, and highly elastic, and can meet the test conditions such as cyclic stretching.
[0014] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], the amorphous alloy is a zirconium-cobalt-aluminum amorphous alloy. Further, in terms of atomic ratio, the chemical formula of the zirconium-cobalt-aluminum amorphous alloy may be Zr 56 Co 28 Al 16 , which has strong amorphous formation ability and strong antioxidant ability, and is convenient for performing long-term cyclic stretching experiments.
[0015] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], the cyclic test is a cyclic stretching test.
[0016] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], a Kelvin probe microscope is used for potential testing to characterize the surface potential distribution of the amorphous alloy, obtain the surface potential difference of the amorphous alloy, and calculate the surface electron work function of the amorphous alloy from the obtained surface potential difference.
[0017] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], the electron work function is obtained by calculation using the following formula:
[0018]
[0019] Where and are the electron work functions of the Kelvin probe and the amorphous alloy surface respectively, e represents charge, and V CPD represents the surface potential difference.
[0020] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], the parameters for potential testing using a Kelvin probe microscope are: scanning range 50 μm, scanning rate 0.9 Hz.
[0021] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], the probe model used in the Kelvin probe microscope is SCM-PIT-V2, and the tip radius is 25 nm.
[0022] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], the surface roughness of the amorphous alloy is less than 5 nm.
[0023] In some embodiments, for the non-destructive testing method of the surface quality of the amorphous alloy described in [1], the thickness of the amorphous alloy is 50 nm to 10 μm.
[0024] [2] Application of the non-destructive testing method of the surface quality of the amorphous alloy described in [1] in evaluating the service life of the amorphous alloy.
[0025] Compared with the prior art, the beneficial effects of the present invention are:
[0026] The present invention uses a Kelvin probe to measure the potential difference and further calculates the electron work function, and uses an atomic force microscope to observe the shear band situation on the sample surface for verification. Based on the set samples, the electron work functions of the amorphous alloy films with different numbers of cyclic tensile times are corresponded to the observed shear band situations one by one, so as to verify that the surface electron work function obtained by testing can reflect the material quality, and thus a non-destructive testing method based on a Kelvin probe microscope can be obtained. Description of the Drawings
[0027] Figure 1 It is a schematic diagram of the non-destructive testing system based on a Kelvin probe microscope proposed in the specific embodiment of the present invention.
[0028] Figure 2 It is a schematic diagram and experimental parameters of cyclic tensile provided in the specific embodiment of the present invention.
[0029] Figure 3 It is a schematic diagram of the principle of a Kelvin probe microscope for measuring the electron work function provided in the specific embodiment of the present invention.
[0030] Figure 4This is the electron work function diagram of samples with different cyclic stretching times provided in the specific embodiments of the present invention.
[0031] Figure 5 This is the surface topography photo before the generation of shear bands provided in the specific embodiments of the present invention, where: (a) the surface topography photo of the thin film when the cyclic stretching times is 0; (b) the surface topography photo of the thin film when the cyclic stretching times is 500; (c) the surface topography photo of the thin film when the cyclic stretching times is 1000.
[0032] Figure 6 This is the surface topography photo after the generation of shear bands provided in the specific embodiments of the present invention, where: (a) the surface topography photo of the thin film when the cyclic stretching times is 1500; (b) the surface topography photo of the thin film when the cyclic stretching times is 2000; (c) the surface topography photo of the thin film when the cyclic stretching times is 2500; (d) the surface topography photo of the thin film when the cyclic stretching times is 3000. Specific embodiments
[0033] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. The operating methods without specific conditions noted in the following embodiments are usually in accordance with conventional conditions or in accordance with the conditions recommended by the manufacturer.
[0034] The present invention proposes a non-destructive detection method for the surface quality of amorphous alloys based on detecting the surface electron work function by a Kelvin probe microscope, and its detection system is as Figure 1 shown, which can be divided into two parts: a detection probe and a computer. First, the potential difference between the sample to be measured and the probe is measured by the detection probe, and then the potential difference image of the test area is established on the Nano Scope Analysis software to determine the electron work function of the sample to be measured. When defects such as shear bands and cracks appear on the material surface, the electron work function will mutate.
[0035] A non-destructive detection method for the surface quality of amorphous alloys based on detecting the surface electron work function by a Kelvin probe microscope includes the following steps:
[0036] 1) Obtain a substrate and an alloy target.
[0037] 2) Deposit a uniform amorphous alloy thin film on the surface of the substrate by physical vapor deposition (PVD) co-sputtering technology. In the implementation, the sample holder rotation motor should be turned on to obtain an amorphous alloy thin film with uniform composition.
[0038] 3) Perform Kelvin probe measurement of the potential difference V on each cyclic stretching sample CPD, and then calculate the electronic work function through Equation (1) introduced above, and record the change trend of the electronic work function with the increase of the number of cyclic stretching times.
[0039] 5) Observe the surface morphology of each cyclic stretching sample under an atomic force microscope to verify that the monitoring of the sample surface quality by the electronic work function is reliable.
[0040] The physical vapor deposition co-sputtering in the present invention can be any one of magnetron sputtering, evaporation coating, and ink printing, and is not limited thereto.
[0041] When the method of the present invention is executed, a Kelvin probe microscope can be used for potential testing to characterize the potential of the sample surface, obtain the surface potential difference of each amorphous alloy, and calculate the electronic work function of each amorphous alloy surface through the obtained surface potential difference. When the electronic work function undergoes a mutation, shear band failure occurs on the amorphous alloy surface, and the quality of the amorphous alloy can be monitored online.
[0042] The present invention can determine the change of the electronic work function of the amorphous alloy thin film sample by measuring the change of the potential difference of the amorphous alloy thin film sample under different numbers of cyclic stretching times, so as to realize the online monitoring of the film quality. Further, an atomic force microscope can be used to verify whether shear bands start to germinate in the area where the electronic work function mutates.
[0043] The present invention uses a Kelvin probe microscope for potential testing to characterize the surface potential of each sample, obtain the surface potential difference of each amorphous thin film and the potential difference distribution image between each amorphous thin film and the Kelvin probe, and obtain the average potential difference between each amorphous thin film and the Kelvin probe through image processing as the surface potential difference.
[0044] The following introduces specific embodiments, and the steps are as follows:
[0045] 1. Preparation of Zr-Co-Al ternary alloy sample:
[0046] A sample was deposited and synthesized by physical vapor deposition co-sputtering, and targets of alloy components Zr 56 Co 28 Al 16 were used to prepare a single-component thin film on a PET substrate. The radio frequency power was 130 W. The sputtering parameters provided by the specific embodiment of the present invention were that the basic pressure in the chamber was lower than 10 -5 Pa, the working pressure was 0.35 Pa, and the flow rate of argon was 30 SCCM. The deposition was carried out for 180 min.
[0047] To meet the precondition of mechanical property testing, an atomic force microscope (AFM) was used for measurement. The roughness of this sample library was about 2 nm, and the thickness was about 800 nm.
[0048] 2. Cyclic tensile test:
[0049] In order to obtain films with different surface qualities, cyclic stretching was performed for different times (0, 500, 1000, 1500, 2000, 2500, and 3000 times) under a 1KN universal material testing machine, with a tensile strain of 2% and a frequency of 220 Hz. The experimental schematic diagram and experimental parameters of cyclic stretching are shown in Figure 2. Figure 2 .
[0050] 3. Perform Kelvin probe measurement. The principle of Kelvin probe microscope test is as follows: Figure 3 As shown:
[0051] 3.1. Before testing the sample, measure the probe electron work function value first, and fix the gold standard sample with a known electron work function of 5.1 eV on the sample stage.
[0052] 3.2. Observe through the lens that the sample surface is smooth and flat to ensure that the probe can perform the test normally.
[0053] 3.3. Adjust the test parameters: scanning range 50 microns, scanning rate 0.9 Hz, the probe model used is SCM-PIT-V2, and the needle tip radius is 25 nm.
[0054] 3.4. Scan and obtain the potential difference between the gold standard and the probe to be 0.55V. Then calculate the electron work function of the probe using the formula: is 5.65eV:
[0055] 3.5. Take out the standard sample, and then place the sample obtained in step 1 flat on the AFM sample stage, and fix it on the test platform to prevent the sample from sliding during the test.
[0056] 3.6. Measure the potential of each sample in accordance with the test parameters of the standard sample potential.
[0057] 3.7. The average potential difference of each sample is summarized as shown in Table 1.
[0058] Table 1 Average potential difference of different samples (V)
[0059]
[0060] 3.8. The corresponding electron work function values are calculated by equation (1), as shown in Table 2.
[0061] Table 2 Electronic work function values of different samples (eV)
[0062]
[0063] 3.9 Measure the magnitude of the surface potential difference for each sample, and obtain the corresponding electron work function value of the sample by integrating the data, as Figure 4 shown.
[0064] 4 Observe the surface quality of the thin film under an atomic force microscope.
[0065] 4.1 Place the sample obtained in step 1 flat in the atomic force microscope and fix it on the test platform to prevent the sample from sliding during the test.
[0066] 4.2 Observe the surface quality of the sample. The surface morphologies of the samples treated with different cyclic tensile numbers are as Figure 5 、 Figure 6 shown. It is found that before the sudden change of the electron work function, that is, when the cyclic tensile numbers are 0, 500, and 1000 times (as Figure 5 ), the surface of the sample is smooth and no shear bands are generated; when the electron work function undergoes a sudden change (as Figure 6 (a)), fine shear bands are generated on the surface of the sample with 1500 cyclic tensile times, and the average height is 80 nm. At the same time, with the increase of the cyclic tensile number, the height of the shear bands on the sample surface gradually increases: for the sample with 2000 cyclic tensile times, the average height of the surface shear bands is 110 nm; for the sample with 2500 cyclic tensile times, the average height of the surface shear bands is 150 nm; for the sample with 3000 cyclic tensile times, the average height of the surface shear bands is 180 nm. With the increase of the shear band height, the surface quality of the amorphous alloy further deteriorates, and the corresponding electron work function also gradually decreases.
[0067] The above examples show that using a Kelvin microscope to detect the electron work function can perform in-situ, rapid, and non-destructive detection of the surface quality of amorphous alloys, and can sensitively capture the occurrence of surface micro-failure events.
[0068] Although the present invention has been described to a certain extent, the non-destructive detection method based on the electronic work function of the present invention is not limited to the detection by a Kelvin probe microscope, but also includes other methods for detecting the electronic work function by experimental equipment. This method is not limited to the detection of surface quality, and the generation of internal defects in amorphous alloys can also be detected based on this method. This method is applicable to various forms of amorphous alloy samples and devices, such as thin films, strips, bulk materials, etc. In addition, it should be noted that although crystalline alloys have structural defects such as dislocations and grain boundaries, after determining the initial state of the electronic work function, with the evolution of external conditions, the change in the electronic work function can also reflect the changes in surface quality and internal defects. Therefore, by appropriately changing the conditions described in the present specification, it is also applicable to crystalline alloys. Without departing from the spirit and scope of the present invention, appropriate changes can be made to each condition. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.
Claims
1. A non-destructive testing method for the surface quality of amorphous alloys, characterized in that, Including: Perform cyclic tests on the amorphous alloy with a sound surface according to the service conditions until shear band failure first appears on the surface of the amorphous alloy, and detect the surface electronic work function of the amorphous alloy at this time Detect the surface electron work function of the amorphous alloy to be measured with the same composition If it is considered that the surface quality of the amorphous alloy to be measured is good, otherwise it is considered that shear band failure has occurred on the surface of the amorphous alloy to be measured.
2. The non-destructive testing method for the surface quality of amorphous alloys according to claim 1, characterized in that, The amorphous alloy is a thin film sample.
3. The non-destructive testing method for the surface quality of amorphous alloys according to claim 2, wherein The substrate material of the amorphous alloy thin film is a flexible material, specifically including polyethylene terephthalate.
4. The non-destructive testing method for the surface quality of amorphous alloys according to any one of claims 1 to 3, characterized in that, The amorphous alloy is a zirconium-cobalt-aluminum amorphous alloy.
5. The non-destructive testing method for the surface quality of amorphous alloys according to claim 4, characterized in that In terms of atomic ratio, the chemical formula of the zirconium-cobalt-aluminum amorphous alloy is Zr 56 Co 28 Al 16 .
6. The non-destructive testing method for the surface quality of amorphous alloys according to any one of claims 1 to 3, characterized in that The cyclic test is a cyclic tensile test.
7. The non-destructive testing method for the surface quality of amorphous alloys according to claim 1, characterized in that, The potential test is carried out by a Kelvin probe microscope to characterize the surface potential distribution of the amorphous alloy, obtain the surface potential difference of the amorphous alloy, and calculate the surface electron work function of the amorphous alloy through the obtained surface potential difference.
8. The non-destructive testing method for the surface quality of amorphous alloys according to claim 7, characterized in that, The electron work function is obtained by calculating according to the following formula: wherein, and are the electron work functions of the Kelvin probe and the amorphous alloy surface respectively, e represents charge, and V CPD represents the surface potential difference.
9. The non-destructive testing method for the surface quality of the amorphous alloy according to claim 7, wherein, The parameters for the potential test using the Kelvin probe microscope are: scanning range 50 microns, scanning rate 0.9 Hz; The probe model used in the Kelvin probe microscope is SCM-PIT-V2, and the tip radius is 25 nm; The surface roughness of the amorphous alloy is less than 5 nanometers; The thickness of the amorphous alloy is 50 nanometers to 10 microns.
10. Application of the non-destructive testing method for the surface quality of the amorphous alloy according to any one of claims 1 to 9 in evaluating the service life of the amorphous alloy.