Device and method for detecting thinning rate of stamped metal bipolar plate of hydrogen fuel cell

Abstract

The invention relates to the technical field of hydrogen fuel cell metal bipolar plate detection, in particular to a device and method for detecting the thinning rate of a hydrogen fuel cell metal bipolar plate after stamping, the device comprises a detection platform, a polar plate fixing tool, an appearance contour measuring instrument and a bidirectional probe, and the bidirectional probe is fixed on a driver of the appearance contour measuring instrument. The polar plate fixing tool comprises a rotatable bench vice, a bearing flat plate and a flattening gauge block, the appearance contour measuring instrument is placed on the detection platform, the bearing flat plate is clamped above the rotatable bench vice, a metal bipolar plate to be detected is flatly placed on the bearing flat plate, the flattening gauge block is placed on the metal bipolar plate, an upper notch is formed in the flattening gauge block, and a lower notch is formed in the flattening gauge block. The object bearing flat plate is provided with a lower notch, the upper notch and the lower notch are arranged in an up-down alignment mode, and the method is that the device is adopted to detect the thinning rate of the metal bipolar plate. The device is simple and reliable in structure and convenient to operate, and the detection method has the advantages of being safe, efficient, wide in function, accurate in detection result and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydrogen fuel cell metal bipolar plate detection, in particular to a device and method for detecting the thinning rate of a hydrogen fuel cell metal bipolar plate after stamping. BACKGROUND

[0002] The raw material used by the hydrogen fuel cell metal bipolar plate is generally a coil with a thickness of about 0.1 mm. In the production process of the hydrogen fuel cell, the thickness of each part of the metal bipolar plate after stamping is detected to evaluate the thinning of the base material after stamping, and then the stamping process is adjusted according to the detection results to ensure that each part of the metal bipolar plate after stamping does not have a serious thinning problem. In the industry, the thinning rate is generally controlled to be no more than 30%.

[0003] Currently, the detection and evaluation of the thinning rate of the hydrogen fuel cell metal bipolar plate after stamping in the industry usually uses a medium-wire wire cutting machine or a three-ion beam cutting machine to prepare samples, and then detects the samples on a metallographic microscope. This detection method mainly has the following technical defects: (1) The samples can only be detected after being prepared, and the detection method is complex and the detection time is long; (2) The sampled part is prone to deformation during the sample preparation process, which affects the accuracy of the detection results; (3) The sample preparation is a destructive detection, which has the problems of detection waste and high detection cost.

[0004] Therefore, the field needs to be improved. SUMMARY

[0005] The purpose of the present application is to provide a device and method for detecting the thinning rate of a hydrogen fuel cell metal bipolar plate after stamping to solve the problem of how to conveniently and quickly detect the thinning of the base material after stamping without damaging the base material, so as to better guide the stamping process of the metal bipolar plate.

[0006] In order to realize one of the above-mentioned purposes, the present application provides a detection device for the thinning rate of a hydrogen fuel cell metal bipolar plate after stamping, which comprises a detection platform, a plate fixing tool, an appearance contour measuring instrument and a bidirectional measuring needle, the bidirectional measuring needle is fixed on the driver of the appearance contour measuring instrument, the plate fixing tool comprises a rotatable bench vice, a supporting plate and a flattening block, the appearance contour measuring instrument and the rotatable bench vice are respectively placed on the detection platform, the supporting plate is clamped above the rotatable bench vice, the metal bipolar plate to be detected is placed on the supporting plate, the flattening block is placed on the metal bipolar plate to realize the flattening and compaction of the metal bipolar plate, an upper gap is arranged on the flattening block, a lower gap is arranged on the supporting plate, the upper gap and the lower gap are arranged in alignment, and the appearance contour measuring instrument drives the bidirectional measuring needle to detect the upper and lower surfaces of the metal bipolar plate between the upper gap and the lower gap.

[0007] Preferably, the model of the appearance contour measuring instrument is W820RC-500 or FTA-H4D4000-D.

[0008] Preferably, the appearance contour measuring instrument is matched with an Evovis measuring and evaluating software.

[0009] Preferably, the bidirectional measuring needle is fixed on the driver of the appearance contour measuring instrument through a magnetic or buckle connection structure.

[0010] Preferably, the front end of the bidirectional measuring needle is provided with two needle-shaped structure needle tips of hard alloy material, and the middle part of the bidirectional measuring needle is an elongated cylindrical structure measuring rod, and the tail part of the measuring rod is provided with a magnet block or a buckle.

[0011] Based on another purpose of the present application, a detection method for the thinning rate of a hydrogen fuel cell metal bipolar plate after stamping is provided, which is detected by the detection device for the thinning rate of a hydrogen fuel cell metal bipolar plate after stamping and comprises the following steps: S1, starting the appearance contour measuring instrument, moving the lower needle tip of the bidirectional measuring needle to the specified position on the upper surface of the metal bipolar plate according to the set measuring program, and measuring a certain distance on the upper surface of the metal bipolar plate by the bidirectional measuring needle; then the bidirectional measuring needle is withdrawn and moved to the same position on the lower surface of the metal bipolar plate, the upper needle tip of the bidirectional measuring needle is controlled to measure the same distance on the lower surface of the metal bipolar plate, and after the measurement of the upper and lower surfaces of the metal bipolar plate is completed, the appearance contour measuring instrument automatically generates a measurement contour; S2, the operator manually marks the thickness a of each part and other items to be detected on the measurement contour according to the detection needs, and then records the thickness of each part; S3, find out the thickness of the base material before stamping, and finally calculate the thinning rate of the metal bipolar plate after stamping according to the thinning rate calculation formula.

[0012] Preferably, in step S1, the contact force of the bidirectional probe with the metal bipolar plate during detection is less than 20 mN.

[0013] Preferably, in step S3, the thinning rate calculation formula is as follows: Thinning rate = (b-a) / b x 100% Wherein, a is the thickness value of a certain part of the metal bipolar plate after stamping, and b is the thickness value of the base material before stamping.

[0014] The detection process of the present application is: starting the appearance contour measuring instrument → setting the measurement program → installing the bidirectional probe → adjusting the bipolar plate fixing tooling → installing the metal bipolar plate → moving the bidirectional probe to the specified position → starting the measurement program detection → the software of the appearance contour measuring instrument generates the measurement contour → the operator marks the size → calculates the thinning rate.

[0015] The present application also includes other components or steps that can enable it to be used normally, which are conventional means in the art, in addition, the devices or components not specified in the present application, such as the detection platform, the appearance contour measuring instrument, the rotatable bench vice, the magnetic type connecting structure, the buckle type connecting structure, etc. all adopt the mature structure or product in the prior art.

[0016] Compared with the prior art, the present application has the following technical effects: 1. It belongs to non-destructive testing, which can avoid detection waste.

[0017] 2. The bidirectional probe contact type measurement is adopted to efficiently complete the contour detection of both sides of the metal bipolar plate, which is efficient and accurate.

[0018] 3. The contact force during detection is less than 20 mN, and the metal bipolar plate will not be deformed, so the detection result is accurate.

[0019] 4. In addition to detecting the thinning rate, the appearance contour of the metal bipolar plate can also be detected during the detection process, such as the width, depth, arc, angle, etc. of the flow channel part.

[0020] As can be seen from the above, the device of the present application has the advantages of simple and reliable structure, convenient operation, safe and efficient detection method, wide function and accurate detection result. BRIEF DESCRIPTION OF DRAWINGS

[0021] The present application will be further described below in conjunction with the drawings and examples.

[0022] Figure 1 It is the overall structure schematic diagram of the present application in example 1.

[0023] Figure 2 This is a schematic diagram of the overall structure of the bidirectional probe of the present invention in Example 1.

[0024] Figure 3 This is the first detection chart obtained during the detection process of the present invention in Example 2.

[0025] Figure 4 This is the second detection chart obtained during the detection process of the present invention in Example 2.

[0026] Figure 5 This is Graph 3, obtained during the detection process of the present invention in Example 2. Detailed Implementation

[0027] The present invention will now be clearly described with reference to the accompanying drawings and specific embodiments. This description is merely illustrative and is not intended to limit the scope of the invention. Any modifications, equivalent substitutions, or improvements made by those skilled in the art based on the embodiments of the present invention without inventive effort to obtain all other embodiments should be included within the scope of protection of the present invention.

[0028] Example 1 like Figures 1-2 As shown, the device for detecting the thinning rate of hydrogen fuel cell metal bipolar plates after stamping provided in this embodiment includes a detection platform 1, a plate fixing fixture, an appearance contour measuring instrument 2, and a bidirectional probe 3. The bidirectional probe is fixed on the driver 21 of the appearance contour measuring instrument. The plate fixing fixture includes a rotatable stage vise 4, a support plate 5, and a flattening block 6. The appearance contour measuring instrument and the rotatable stage vise are placed on the detection platform, and the support plate is clamped above the rotatable stage vise (in this embodiment, the bottom of the support plate is provided with a fixing part for clamping the rotatable stage vise). The metal bipolar plate 7 to be tested is placed flat on the support plate, and the flattening block is placed on top of the metal bipolar plate to achieve flattening and compaction of the metal bipolar plate. The flattening block has an upper notch, and the support plate has a lower notch. The upper and lower notches are aligned vertically. The appearance contour measuring instrument drives the bidirectional probe to perform appearance contour detection on the upper and lower surfaces of the metal bipolar plate between the upper and lower notches through the driver.

[0029] In this embodiment, the appearance profile measuring instrument is the W820RC-500 roughness and profile measuring instrument integrated machine from the German company, Hormel. The appearance profile measuring instrument is equipped with Evovis measurement and evaluation software, and the bidirectional probe is fixed to the driver of the appearance profile measuring instrument through a magnetic connection structure.

[0030] Specifically, the front end of the bidirectional measuring needle is provided with two needle-shaped structure hard alloy material needle tips 31, and the middle part of the bidirectional measuring needle is an elongated cylindrical structure measuring rod 32, and the tail part of the measuring rod is provided with a magnet block 33.

[0031] The detection process of the present application is as follows: starting the appearance contour measuring instrument, setting the measurement program, installing the bidirectional measuring needle, adjusting the polar plate fixing tool, installing the metal bipolar plate, moving the bidirectional measuring needle to the specified position, starting the measurement program detection, and the appearance contour measuring instrument generates the measurement contour through the software, and the operator marks the size.

[0032] Embodiment 2 The detection method for the thinning rate of the hydrogen fuel cell metal bipolar plate after stamping provided in the present embodiment uses the detection device for the thinning rate of the hydrogen fuel cell metal bipolar plate after stamping in embodiment 1 for detection, and includes the following steps: S1, start the appearance contour measuring instrument, control the lower needle tip of the bidirectional measuring needle to move to the specified position on the upper surface of the metal bipolar plate according to the set measurement program, so that the bidirectional measuring needle measures a set distance on the upper surface of the metal bipolar plate, then the bidirectional measuring needle exits and moves to the same position on the lower surface of the metal bipolar plate, and the upper needle tip of the bidirectional measuring needle measures the same distance on the lower surface of the metal bipolar plate, after the measurement of the upper and lower surfaces of the metal bipolar plate is completed, the appearance contour measuring instrument automatically generates a measurement contour; S2, the operator manually marks the thickness a of each part and other items to be detected on the measurement contour according to the detection needs, and then records the thickness of each part; S3, find the thickness of the base material before stamping, and finally calculate the thinning rate of the metal bipolar plate after stamping according to the thinning rate calculation formula.

[0033] In step S1, the contact force between the bidirectional measuring needle and the metal bipolar plate during detection is less than 20 mN.

[0034] Specifically, in step S3, the thinning rate calculation formula is as follows: Thinning rate = (b-a) / b x 100% Wherein, a is the thickness value of a certain part of the metal bipolar plate after stamping, and b is the thickness value of the base material before stamping.

[0035] The specific work flow of the present application is as follows: 1, Turn on the power supply of the appearance contour measuring instrument, open the measuring software of the appearance contour measuring instrument, set the basic parameters, for example, the detection distance is 10mm, the measuring speed is 0.5mm / s, the measuring point spacing is 0.5um, and the detection force is 10mN; then set the measuring program, the measuring program mainly includes the moving action of the bidirectional measuring needle and the setting of other parameters. The following is an enumerated measuring program, and the patent protection is not limited to the following parameter settings and the content of the measuring program: 1) Program version number: 01.00 2) Process Main() 3) Assign variable table 4) Pop-up dialog box: text "Move the measuring needle to a safe position and clamp the workpiece" 5) Determine the starting position: absolute position P: 0.0mm 6) Pop-up dialog box: text "1. The measuring arm is in the horizontal position; 2. Move the measuring arm to a position 10mm away from the workpiece" 7) Accept position: return value Start; text "Click to accept the current position to continue" 8) Set the measurement layout: select the measurement direction of the measuring needle, measure downward; 9) Raise the measuring needle by 9mm: absolute position P: 9.0mm 10) Set the positioning speed: positioning speed X: 10.0mm / s 11) Move the measuring needle to the measurement position: relative position X: -30.000mm 12) Lower the measuring needle by 9mm: absolute position P: 9.0mm 13) Measuring needle contact: the measuring needle slowly descends to contact the work surface with the set detection force 14) Start measurement: the measuring needle starts measuring with the set measurement distance 15) Raise the measuring needle by 9mm: absolute position P: 9.0mm 16) Return to the starting position: return value Start 17) Set the measurement layout: select the measurement direction of the measuring needle, measure upward; 18) Raise the measuring needle by 9mm: absolute position P: 9.0mm 19) Move the measuring needle to the measurement position: relative position X: -30.000mm 20) Lower the measuring needle by 9mm: absolute position P: 9.0mm 21) Measuring needle contact: the measuring needle slowly ascends to contact the work surface with the set detection force 22) Start measurement: the measuring needle starts measuring with the set measurement distance 23) Raise the measuring needle by 9mm: absolute position P: 9.0mm 24) Return to start position: return value Start 25) Measurement end 2, the bidirectional measuring needle is adsorbed and mounted on the driver of the appearance profile measuring instrument through the magnetic attraction type connecting structure.

[0036] 3, the rotatable bench vice is placed on the detection platform, and in the embodiment, the detection platform selects a marble platform, and the object supporting flat plate is clamped above the rotatable bench vice.

[0037] 4, the metal bipolar plate is placed flat on the object supporting flat plate, and the flattening block is placed on the metal bipolar plate, so that the flattening and compaction of the metal bipolar plate are realized, and the warping deformation of the metal bipolar plate is avoided to affect the detection result. When the flattening block is placed, the upper gap on the flattening block is aligned with the lower gap on the object supporting flat plate.

[0038] 5, the control box is operated to move the bidirectional measuring needle to be about 10 mm away from the outside of the metal bipolar plate to be measured, and the top end of the bidirectional measuring needle is aligned with the outside of the metal bipolar plate to be measured in the height direction.

[0039] 6, the measurement program is started, and the bidirectional measuring needle is automatically operated to complete the measurement under the driving of the driver.

[0040] 7, after the measurement program is completed, the software automatically simulates the generation of the measurement profile, and then the operator manually marks the thickness a of each part and other items to be detected on the measurement profile according to the detection content.

[0041] 8, the thickness a of each part of the metal bipolar plate is recorded, and the value b of the thickness of the base material before stamping is found out, and finally the thinning rate of the metal bipolar plate after stamping can be calculated according to the above formula: Thinning rate = (b-a) / b x 100% The detection data of a certain type of metal bipolar plate by using the embodiment is listed in Table 1 below, Figures 3-5 The corresponding detection graph in the embodiment is shown in Table 1.

[0042] Table 1: Detection data of a certain type of metal bipolar plate in the embodiment

[0043] According to Figures 3-5 and Table 1, the technical scheme of the present application can detect the appearance profile of the metal bipolar plate, such as the width, depth, arc and angle of the runner part, and has the advantages of safety, high efficiency and accurate detection result.

[0044] Embodiments of the application have been described above, with examples of the description being illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations of the described embodiments are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A device for detecting the thinning rate of metal bipolar plates in hydrogen fuel cells after stamping, characterized in that, The device includes a testing platform, a plate fixing fixture, a bidirectional probe, and a bidirectional probe. The bidirectional probe is fixed to the driver of the bidirectional probe. The plate fixing fixture includes a rotatable vise, a support plate, and a flattening block. The bidirectional probe and the rotatable vise are placed on the testing platform. The support plate is clamped above the rotatable vise. The metal bipolar plate to be tested is placed flat on the support plate. The flattening block is placed on top of the metal bipolar plate to flatten and compact it. The flattening block has an upper notch, and the support plate has a lower notch. The upper and lower notches are aligned vertically. The bidirectional probe is driven by the driver to perform bidirectional probe detection on the upper and lower surfaces of the metal bipolar plate between the upper and lower notches.

2. The device for detecting the thinning rate of metal bipolar plates in hydrogen fuel cells after stamping, as described in claim 1, is characterized in that, The model of the appearance contour measuring instrument is W820RC-500 or FTA-H4D4000-D.

3. The device for detecting the thinning rate of hydrogen fuel cell metal bipolar plates after stamping according to claim 2, characterized in that, The appearance contour measuring instrument is equipped with Evovis measurement and evaluation software.

4. The device for detecting the thinning rate of hydrogen fuel cell metal bipolar plates after stamping according to claim 2, characterized in that, The bidirectional probe is fixed to the driver of the appearance contour measuring instrument via a magnetic or snap-fit ​​connection structure.

5. The device for detecting the thinning rate of hydrogen fuel cell metal bipolar plates after stamping according to claim 4, characterized in that, The bidirectional probe has two needle tips made of hard alloy material with needle-like structures at the front end, and the middle part of the bidirectional probe is a slender cylindrical probe rod. The tail of the probe rod is provided with a magnet or a buckle.

6. A method for detecting the thinning rate of metal bipolar plates in hydrogen fuel cells after stamping, characterized in that: The detection is performed using the device for detecting the thinning rate of the metal bipolar plate of a hydrogen fuel cell after stamping, as described in any one of claims 1 to 5, and includes the following steps: S1. Start the appearance profile measuring instrument. According to the set measurement program, control the lower tip of the bidirectional probe to move to the designated position on the upper surface of the metal bipolar plate, so that the bidirectional probe measures a set distance on the upper surface of the metal bipolar plate. Then, the bidirectional probe retracts and moves to the same position on the lower surface of the metal bipolar plate. Control the upper tip of the bidirectional probe to measure the same distance on the lower surface of the metal bipolar plate. After the measurement of the upper and lower surfaces of the metal bipolar plate is completed, the appearance profile measuring instrument will automatically simulate and generate the measurement profile. S2, The operator manually marks the thickness 'a' of each part and other items to be tested on the measurement profile according to the testing requirements, and then records the thickness of each part. S3, find the thickness of the substrate before stamping, and finally calculate the thinning rate of the metal bipolar plate after stamping according to the thinning rate calculation formula.

7. The method for detecting the thinning rate of hydrogen fuel cell metal bipolar plates after stamping according to claim 6, characterized in that: In step S1, the contact force between the bidirectional probe and the metal bipolar plate during the detection process is less than 20mN.

8. The method for detecting the thinning rate of hydrogen fuel cell metal bipolar plates after stamping according to claim 6, characterized in that: In step S3, the formula for calculating the thinning rate is as follows: Thinning rate = (ba) / b × 100% Where a is the thickness of a certain part of the metal bipolar plate after stamping, and b is the thickness of the substrate before stamping.

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