A device and method for dynamic hydrogen charging tensile test of plate-shaped tensile specimen

Abstract

A device and method for dynamic hydrogen charging tensile test of plate-shaped sample, belonging to the field of material testing technology. The device solves the problem of lack of sealing and insulation function in electrochemical environment or incompatibility with plate-shaped sample of the existing clamp device. The center of the lower clamp is provided with a first clamping station, which is clamped and fixed with the first clamping section. The bottom of the solution pool is provided with a first through hole opposite to the first clamping station. The solution pool is installed on the side of the plate-shaped tensile sample through the first through hole. The periphery of the lower clamp is provided with a stage, and the solution pool is fixed on the stage. The solution pool contains hydrogen charging solution, and the gauge length section of the plate-shaped tensile sample is placed in the hydrogen charging solution for hydrogen charging, ensuring the accuracy of the subsequent measured tensile properties and other sensitive data, and more accurately reflecting the state of the gauge length section material in a specific hydrogen environment, improving the scientific nature of the test data.

Description

Technical Field

[0001] This invention relates to the field of materials testing technology, and in particular to a device and method for dynamic hydrogen-filled tensile testing of plate-shaped specimens. Background Technology

[0002] Hydrogen atoms have the smallest atomic radius and readily diffuse in metals, leading to embrittlement and even fracture of metallic materials—a phenomenon known as hydrogen-induced cracking. Hydrogen-induced cracking can be broadly categorized into two types: First, hydride-forming systems, where hydrides form and, due to their brittle nature, cause brittle fracture. Second, non-hydride-forming systems, where hydrogen atoms affect the material in a solid solution state, influenced by weak bonding mechanisms and theories such as hydrogen-promoted localized plastic deformation.

[0003] In studies of the hydrogen-induced cracking susceptibility of materials, it is often difficult to prepare standard cylindrical specimens due to limitations in sample preparation equipment or the specifications of the raw materials, such as thin plates. Therefore, using plate-shaped specimens to perform hydrogen-charged tensile tests has significant engineering implications. To ensure a constant current density during electrochemical hydrogen charging, the tensile specimen must be strictly locally sealed, exposing only the gauge length to the electrolyte to eliminate interference from the non-gauge length. Currently, fixtures for such tests still have significant limitations: the non-standard plate-shaped specimen tensile fixture disclosed in patent CN209432592U is only suitable for conventional environments and lacks sealing and insulation functions under electrochemical conditions; while patent CN111735697A achieves dynamic hydrogen charging, it is only compatible with rod-shaped specimens; and patent CN121231219A is designed specifically for CT specimens and is not compatible with plate-shaped specimens. In summary, developing a plate-shaped specimen dynamic hydrogen charging fixture that is easy to install, reliably sealed, and can precisely control the contact area with the solution has significant application value for improving the efficiency and data accuracy of hydrogen embrittlement evaluation of materials. Summary of the Invention

[0004] The present invention aims to solve the above-mentioned problems and provides a device and method for dynamic hydrogen-filled tensile testing of plate-shaped specimens.

[0005] The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a device for dynamic hydrogen-filled tensile testing of plate-shaped specimens, wherein the plate-shaped tensile specimen includes a first clamping section, a second clamping section, and a gauge length section, and includes a clamping device, a solution tank, and a conductive platinum sheet. The clamping device includes an upper clamp and a lower clamp. A first clamping station is provided at the center of the lower clamp, and the first clamping station is clamped and fixed to the first clamping section. A first through hole is provided at the bottom of the solution tank, which is vertically opposite to the first clamping station. The solution tank is installed on the periphery of the plate-shaped tensile specimen through the first through hole. A stage is provided on the periphery of the lower clamp, and the solution tank is fixed to the stage. A second clamping station is provided at the center of the upper clamp, which is vertically opposite to the first clamping station. The second clamping station is clamped and fixed to the second clamping section. The conductive platinum sheet is disposed through the solution tank and the stage. The bottom of the conductive platinum sheet is connected to the positive terminal of a power supply through a wire, and the upper clamp is connected to the negative terminal of a power supply through a wire.

[0006] Furthermore, the first clamping section is convex in shape, and the top of the lower clamp is provided with a sliding groove, and the first clamping section slides along the sliding groove to the first clamping position.

[0007] Furthermore, an oil baffle is provided between the solution pool and the lower clamp.

[0008] Furthermore, an oil baffle ring is provided between the first through hole and the plate-shaped tensile specimen.

[0009] Furthermore, both the upper clamp and the lower clamp are coated with an insulating coating.

[0010] Furthermore, a first threaded hole is formed on the upper clamp, and a screw is connected to the first threaded hole by an internal thread, and the wire is welded to the screw.

[0011] Furthermore, the solution pool is filled with a hydrogen-containing solution, and the height of the hydrogen-containing solution is level with the top of the gauge segment.

[0012] Furthermore, the solution pool and the stage are fixedly connected by a plurality of fastening screws.

[0013] Furthermore, the conductive platinum sheet is sealed to the solution pool using silicone.

[0014] A test method for a dynamic hydrogen-charged tensile testing apparatus for plate-shaped specimens includes the following steps: S1: Fix the plate-shaped tensile specimen in the first clamping position and install the solution pool around the periphery of the plate-shaped tensile specimen. S2: Install the oil baffle ring between the solution pool and the plate tensile specimen; S3: Fix the solution pool onto the lower clamp; S4: Adjust the position of the upper clamp to the second clamping position to clamp and fix the plate tensile specimen; S5: Connect the conductive platinum sheet and the upper clamp to the power supply; S6: Add hydrogen charging solution and output current; S7: Perform a tensile test after the hydrogen charging process has stabilized.

[0015] Compared with the prior art, the present invention has the following advantages: This invention uses upper and lower clamps to hold plate-shaped tensile specimens, ensuring stable clamping. During the tensile test, even if the specimen deforms under stress and eventually fractures, the clamps effectively prevent axial slippage or circumferential rotation, completely eliminating problems such as accidental specimen detachment, test interruption, or invalid data caused by insecure clamping. This stable clamping provides a solid foundation for subsequent coupled tests such as electrochemical hydrogen charging under continuous load, ensuring the safety of the entire test process and the continuity of data acquisition, significantly improving the test success rate. This invention secures the solution tank to the lower clamp by mounting a stage around its periphery, forming a stable integrated unit. During solution addition, experimental operations, or environmental vibrations, the solution tank will not sway, tilt, or shift relative to the lower clamp. This stable connection ensures a constant hydrogen solution level and prevents seal failure or solution leakage due to relative movement, creating a reliable experimental foundation. This invention utilizes a solution tank filled with hydrogen-filled solution, placing the gauge length of a plate-shaped tensile specimen within the solution for hydrogen filling. This significantly reduces the influence of the first and second clamping sections on the test data. The solution tank design ensures that only the gauge length of the specimen is immersed in the electrolyte, while the large-area clamping sections at both ends, used for force transmission, are exposed to air. During the electrochemical hydrogen filling process, hydrogen atoms penetrate only into the material within the gauge length, ensuring that the subsequently measured tensile properties and sensitive data such as hydrogen-induced delayed fracture more purely and accurately reflect the intrinsic behavior of the gauge length material under specific hydrogen conditions, thus improving the scientific rigor and comparability of the test data. In this invention, the upper clamp serves as the working electrode, directly connected to the negative terminal of a DC power supply. The platinum sheet is immersed in the solution and connected to the positive terminal of the power supply. This electrical connection is achieved through pre-integrated wires and terminals, resulting in a robust connection with low resistance. This stable electrical connection ensures that the current density applied to the sample remains constant throughout the hydrogen charging test, thereby enabling controllable and repeatable hydrogen permeation rate and concentration in the metal sample. This provides a stable and reliable electrochemical environment for studying the effects of hydrogen on the mechanical properties of materials. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of the dynamic hydrogen-filled tensile testing device for plate-shaped tensile specimens in this invention. Figure 2 This is a schematic diagram showing the positional relationship between the solution tank and the oil baffle in this invention; Figure 3 This is a schematic diagram of the plate-shaped tensile specimen in this invention; In the figure: 1. Upper clamp; 2. Solution pool; 2-1. First through hole; 3. First threaded hole; 4. Plate-shaped tensile specimen; 4-1. First clamping section; 4-2. Second clamping section; 4-3. Gauge section; 5. Conductive platinum sheet; 6. Oil baffle; 7. Stage; 8. Fastening screw; 9. Oil baffle ring; 10. Lower clamp. Detailed Implementation

[0018] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0021] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0022] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0023] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0024] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0025] See appendix Figure 1-3This embodiment describes a device for dynamic hydrogen-charged tensile testing of plate-shaped specimens. The plate-shaped tensile specimen 4 includes a first clamping section 4-1, a second clamping section 4-2, and a gauge length section 4-3. It includes a clamping device, a solution tank 2, and a conductive platinum sheet 5. The clamping device includes an upper clamp 1 and a lower clamp 10. A first clamping position is provided at the center of the lower clamp 10, and the first clamping position is clamped and fixed to the first clamping section 4-1. The bottom of the solution tank 2 has a first through hole 2-1 that is vertically opposite to the first clamping position. The solution pool 2 is installed on the periphery of the plate-shaped tensile specimen 4 through the first through hole 2-1. The lower clamp 10 is provided with a stage 7 on its periphery. The solution pool 2 is fixed on the stage 7. The upper clamp 1 is provided with a second clamping position at its center, which is vertically opposite to the first clamping position. The second clamping position is clamped and fixed with the second clamping section 4-2. The conductive platinum sheet 5 is disposed through the solution pool 2 and the stage 7. The bottom of the conductive platinum sheet 5 is connected to the positive terminal of the power supply through a wire. The upper clamp 1 is connected to the negative terminal of the power supply through a wire.

[0026] The plate-shaped tensile specimen 4 is clamped by the upper clamp 1 and the lower clamp 10 to ensure stable clamping. During the tensile test, even if the specimen is deformed by force until it breaks, the clamps can effectively prevent axial slippage or circumferential rotation, completely eliminating problems such as accidental specimen drop, test interruption, or invalid data caused by loose clamping. This stable clamping provides a solid foundation for subsequent coupled tests such as electrochemical hydrogen charging under continuous load, ensuring the safety of the entire test process and the continuity of data acquisition, and significantly improving the test success rate. By installing the stage 7 on the periphery of the lower clamp 10 to fix the solution pool 2 and the lower clamp 10, the solution pool 2, the stage 7, and the lower clamp 10 form a stable whole. When adding solution, performing test operations, or when the environment vibrates, the solution pool 2 will not shake, tilt, or shift relative to the lower clamp 10. A stable connection ensures a constant level of the hydrogen-filled solution and prevents seal failure or solution leakage due to relative motion, creating a reliable experimental basis. By placing the gauge length 4-3 of the plate-shaped tensile specimen 4 in the hydrogen-filled solution within the solution tank 2, the influence of the first clamping section 4-1 and the second clamping section 4-2 on the experimental data is significantly reduced. The design of the solution tank 2 ensures that only the gauge length 4-3 of the specimen is immersed in the electrolyte, while the large cross-sectional area clamping sections at both ends used for force transmission are exposed to air. During the electrochemical hydrogen-filling process, hydrogen atoms only penetrate the material within the gauge length 4-3, ensuring that the subsequently measured tensile properties and sensitive data such as hydrogen-induced delayed fracture more purely and accurately reflect the intrinsic behavior of the gauge length 4-3 material under specific hydrogen conditions, improving the scientific rigor and comparability of the experimental data. The upper clamp 1, acting as the working electrode, is directly connected to the negative terminal of the DC power supply, while the platinum sheet is immersed in the solution and connected to the positive terminal of the power supply. This electrical connection is achieved through pre-integrated wires and terminals, resulting in a robust connection with low resistance. Stable electrical connection ensures that the current density applied to the sample remains constant throughout the hydrogen charging test, thereby enabling controllable and repeatable hydrogen permeation rate and concentration in the metal sample, providing a stable and reliable electrochemical environment for studying the effects of hydrogen on the mechanical properties of materials.

[0027] The first clamping section 4-1 is convex in shape, and the top of the lower clamp 10 is provided with a sliding groove. The first clamping section 4-1 slides along the sliding groove to the first clamping position. By using the convex first clamping section 4-1 in conjunction with the sliding groove, the positioning is accurate after sliding into place, ensuring that the sample is installed quickly and accurately, and effectively transmitting axial tensile force, thereby improving testing efficiency and accuracy.

[0028] An oil baffle 6 is provided between the solution pool 2 and the lower clamp 10. By placing the oil baffle 6 on the lower clamp 10, the oil baffle 6 can effectively isolate the solution pool 2 from the lower clamp 10, solve the problem of hydrogen filling solution leakage, prevent the hydrogen filling solution from corroding the clamp, and ensure the purity of the electrochemical environment and the long-term reliability of the experimental device.

[0029] An oil-blocking ring 9 is provided between the first through hole 2-1 and the plate-shaped tensile specimen 4. Specifically, the oil-blocking ring 9 is composed of two semi-circular oil-blocking rings 9 assembled together. By installing two oil-blocking rings 9 between the first through hole 2-1 and the plate-shaped tensile specimen 4, the problem of hydrogen-filled solution leakage around the plate-shaped tensile specimen 4 is solved.

[0030] Both the upper clamp 1 and the lower clamp 10 are coated with an insulating coating. This coating forms a continuous and dense insulating layer. The insulating coating effectively prevents reactions between the clamps and the sample, improving the purity of the electrochemical environment and the reliability of the experimental data. This measure enhances the durability, testing accuracy, and operational safety of the device.

[0031] The upper clamp 1 has a first threaded hole 3, and a screw is connected to the first threaded hole 3 by an internal thread. The wire is welded to the screw.

[0032] The solution pool 2 contains a hydrogen-containing solution, and the height of the hydrogen-containing solution is level with the top of the gauge segment 4-3. Specifically, only the gauge segment 4-3 is immersed in the hydrogen-containing solution, while the first clamping segment 4-1 and the second clamping segment 4-2 are both clamped by the upper clamp 1 and the lower clamp 10, and are not within the solution pool 2.

[0033] The solution pool 2 and the stage 7 are fixedly connected by a plurality of fastening screws 8. Preferably, there are three fastening screws 8, and the three fastening screws 8 are evenly distributed circumferentially.

[0034] The conductive platinum sheet 5 is sealed to the solution pool 2 with silicone.

[0035] A test method for a dynamic hydrogen-charged tensile testing apparatus for plate-shaped specimens includes the following steps: S1: Fix the plate-shaped tensile specimen 4 at the first clamping position and install the solution pool 2 around the plate-shaped tensile specimen 4. S2: Install the oil baffle ring 9 between the solution pool 2 and the plate tensile specimen 4; S3: Fix the solution pool 2 onto the lower clamp 10; S4: Adjust the position of the upper clamp 1 to the second clamping position to clamp and fix the plate tensile specimen 4; S5: Connect the conductive platinum sheet 5 and the upper clamp 1 to the power supply. S6: Add hydrogen charging solution and output current; S7: Perform a tensile test after the hydrogen charging process has stabilized.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for dynamic hydrogen-charged tensile testing of plate-shaped specimens, wherein the plate-shaped tensile specimen (4) comprises a first clamping section (4-1), a second clamping section (4-2), and a gauge length section (4-3), characterized in that: The device includes a clamping device, a solution tank (2), and a conductive platinum sheet (5). The clamping device includes an upper clamp (1) and a lower clamp (10). The lower clamp (10) has a first clamping station at its center, which is clamped and fixed to the first clamping section (4-1). The bottom of the solution tank (2) has a first through hole (2-1) that is vertically opposite to the first clamping station. The solution tank (2) is installed on the periphery of the plate-shaped tensile specimen (4) through the first through hole (2-1). The fixture (10) is provided with a stage (7) on its periphery. The solution pool (2) is fixed on the stage (7). The upper clamp (1) is provided with a second clamping station at its center, which is vertically opposite to the first clamping station. The second clamping station is clamped and fixed with the second clamping section (4-2). The conductive platinum sheet (5) is provided through the solution pool (2) and the stage (7). The bottom of the conductive platinum sheet (5) is connected to the positive terminal of the power supply through a wire. The upper clamp (1) is connected to the negative terminal of the power supply through a wire.

2. The apparatus for dynamic hydrogen-charged tensile testing of plate-shaped specimens according to claim 1, characterized in that: The first clamping section (4-1) is convex in shape, and the top of the lower clamp (10) is provided with a sliding groove. The first clamping section (4-1) slides along the sliding groove to the first clamping position.

3. The apparatus for dynamic hydrogen-charged tensile testing of plate-shaped specimens according to claim 1, characterized in that: An oil baffle (6) is provided between the solution pool (2) and the lower clamp (10).

4. The apparatus for dynamic hydrogen-charged tensile testing of plate-shaped specimens according to claim 1, characterized in that: An oil baffle ring (9) is provided between the first through hole (2-1) and the plate-shaped tensile specimen (4).

5. The apparatus for dynamic hydrogen-charged tensile testing of plate-shaped specimens according to claim 1, characterized in that: Both the upper clamp (1) and the lower clamp (10) are coated with an insulating coating.

6. The apparatus for dynamic hydrogen-charged tensile testing of plate-shaped specimens according to claim 1, characterized in that: The upper clamp (1) has a first threaded hole (3), and a screw is connected to the first threaded hole (3) by an internal thread. The wire is welded to the screw.

7. The apparatus for dynamic hydrogen-charged tensile testing of plate-shaped specimens according to claim 1, characterized in that: The solution pool (2) is filled with hydrogen-containing solution, and the height of the hydrogen-containing solution is level with the top of the gauge segment (4-3).

8. The apparatus for dynamic hydrogen-charged tensile testing of plate-shaped specimens according to claim 1, characterized in that: The solution pool (2) and the stage (7) are fixedly connected by a plurality of fastening screws (8).

9. The apparatus for dynamic hydrogen-charged tensile testing of plate-shaped specimens according to claim 1, characterized in that: The conductive platinum sheet (5) and the solution pool (2) are sealed with silicone.

10. A test method for a dynamic hydrogen-charged tensile testing apparatus for plate-shaped specimens as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1: Fix the plate-shaped tensile specimen (4) at the first clamping position and install the solution pool (2) on the periphery of the plate-shaped tensile specimen (4); S2: Install the oil baffle ring (9) between the solution pool (2) and the plate tensile specimen (4); S3: Fix the solution pool (2) onto the lower clamp (10); S4: Adjust the position of the upper clamp (1) to the second clamping position and clamp and fix it with the plate tensile specimen (4); S5: Connect the conductive platinum sheet (5) and the upper clamp (1) to the power supply; S6: Add hydrogen charging solution and output current; S7: Perform a tensile test after the hydrogen charging process has stabilized.

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