Sample detection device for horizontal push rod type dilatometer and application method of sample detection device

Abstract

The invention provides a sample detection device for a horizontal push rod type dilatometer and an application method thereof, and relates to the field of metal material expansion coefficient determination. The sample detection device is suitable for sheet samples and comprises a base and a fixed part arranged on the base, the fixing part comprises a pair of limiting structures which are arranged on one side of a horizontal push rod of the dilatometer and are arranged at intervals in the axial direction, and the side faces, close to each other, of the limiting structures are arranged to be planes perpendicular to the axial direction of the horizontal push rod; a plane is defined as a limiting surface, a pair of limiting grooves are symmetrically formed in the two limiting surfaces, and a sheet-shaped sample arranged in the horizontal direction is installed between the limiting grooves; the base is fixedly arranged in a sample holder of the dilatometer, the contact surface of the base and the limiting structure is smooth, and the base enables the sheet sample to coincide with the central axis of the horizontal push rod along the axial central axis of the horizontal push rod; during application, the sample detection device is combined with the designed aluminum oxide standard sample with the same size as the sample, so that the stable test of the sheet-shaped sample can be fully ensured, and the test result is accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of metal material expansion coefficient measurement, and in particular to a sample detection device for a horizontal push rod expansion instrument and an application method thereof. Background Art

[0002] Silicon steel sheets are a key material for manufacturing transformers, new energy motors, and generator cores. As the temperature of these devices rises during operation, their dimensions will change, affecting their performance or even causing damage. Therefore, accurately understanding the thermal expansion performance parameters of the materials is of great significance to the research and development and high-end applications of metal materials, especially steel materials, and is also crucial to product development and actual use.

[0003] Currently, the linear thermal expansion properties of materials are typically tested using a horizontal push-rod dilatometer. Conventional testing devices are primarily designed for testing standard cylindrical specimens with a diameter of 6 mm and a length of 25 mm. However, the thickness of non-oriented silicon steel sheets typically ranges from 0.20 mm to 0.5 mm, making them sheet-like specimens. Due to their thinness and small end-load surface, sheet specimens present the following challenges: First, the push rod of the horizontal push-rod dilatometer struggles to support the specimen, preventing the load from being applied. Second, due to the thinness of the specimen, the push rod presses against the specimen, causing the specimen to bend and leading to test failure. Furthermore, current horizontal push-rod dilatometers lack compatible testing devices and methods for sheet specimens, making them incapable of performing linear thermal expansion coefficient tests on these specimens. Therefore, it is necessary to develop a sample testing device suitable for horizontal push-rod dilatometers to test the linear thermal expansion of sheet specimens. Summary of the Invention

[0004] The present invention aims to provide a sample detection device for a horizontal push rod dilatometer and an application method thereof. By designing a sample detection device suitable for sheet samples, the problem that the current horizontal push rod dilatometer cannot perform linear thermal expansion tests on sheet samples is solved.

[0005] To achieve the above objectives, the present invention proposes the following technical solutions:

[0006] In a first aspect, a sample detection device for a horizontal push rod dilatometer is provided, which is suitable for sheet samples and includes a base and a fixing portion provided on the base;

[0007] The fixing portion includes a pair of limiting structures, the limiting structures are arranged on one side of the horizontal push rod of the horizontal push rod dilatometer, and the limiting structures are symmetrical along the axis of the horizontal push rod and are arranged on the base at intervals; the two side surfaces of the limiting structures on the base that are close to each other are set as planes, and the planes are perpendicular to the axis of the horizontal push rod;

[0008] The planes where the upper limit structures of the base are close to each other are defined as the limiting surfaces, and a pair of limiting grooves are symmetrically provided on the two limiting surfaces, and the limiting grooves form a sheet sample mounting position; the sheet sample mounting position is used to mount a quadrilateral sheet sample, and when the sheet sample is placed in the sheet sample mounting position, the sheet sample is arranged in a horizontal direction and is perpendicular to the limiting surfaces;

[0009] The base is fixed in the sample holder of the horizontal push rod dilatometer, the contact surface of the base with the limiting structure is smooth, and the base makes the central axis of the sheet sample installation position along the axial direction of the horizontal push rod coincide with the central axis of the horizontal push rod.

[0010] Furthermore, a mounting groove is provided on a side surface of the base close to the fixing portion, the groove surface of the mounting groove is smooth, and the limiting structure is adapted to be engaged in the mounting groove.

[0011] Furthermore, the limiting structure is configured as a cylindrical structure coaxial with the horizontal push rod, the limiting groove is configured on the circular end face of the cylindrical structure, and the limiting groove is centrally symmetrically distributed along the radial direction of the circular end face.

[0012] Furthermore, the limiting groove is set as a rectangular groove, the depth of the rectangular groove along the axial direction of the horizontal push rod is 0.5-1 mm, the length along the radial direction of the circular end face is 5.5-7.5 mm, and the width along the radial direction perpendicular to the circular end face is 2.5-5 mm.

[0013] Furthermore, the base includes a pair of support seats that are symmetrical and spaced apart along the axis of the horizontal push rod. An arc groove is provided on the side of any support seat close to the limiting structure. The axial direction of the arc groove is parallel to the axial direction of the horizontal push rod, and the size of the arc groove is adapted to the outer wall size of the limiting structure.

[0014] Furthermore, the roughness R of the arc groove surface a Not exceeding 0.8μm.

[0015] Furthermore, the base and the fixing portion are both made of aluminum oxide.

[0016] In a second aspect, a method for applying the sample detection device for the horizontal push rod dilatometer is provided, comprising the following steps:

[0017] 1) Obtaining a standard sheet and a sheet sample; wherein the standard sheet is an aluminum oxide sheet having a thickness of 2 to 4 mm, a length of 15 to 20 mm, and a width of 5 to 7 mm, wherein the aluminum oxide purity of the aluminum oxide sheet is not less than 99.9% and the dimensional accuracy of the aluminum oxide sheet in the longitudinal direction does not exceed 0.02%; the sheet sample has the same dimensions as the standard sheet and is composed of multiple neatly stacked metal sheets to be tested;

[0018] 2) Measuring the length of the sheet standard sample, after which the sheet standard sample is horizontally mounted in a pair of limiting grooves of a limiting structure in a sample detection device, and then placing the sample detection device into a sample holder of a horizontal push rod dilatometer. After securing the sample, the horizontal push rod applies a load to the sheet standard sample. During the measurement, the pressure of the horizontal push rod contacting the sheet standard sample is set to 15 to 30 cN, and the temperature is raised at a rate of 3 to 5°C / min to each preset temperature, thereby obtaining a linear thermal expansion baseline of the sheet standard sample.

[0019] 3) Measure the length of the sheet sample. After the measurement, horizontally install the sheet sample in a pair of limiting grooves of the limiting structure of the sample detection device. Then, place the sample detection device in the sample holder of the horizontal push rod dilatometer. After fixing, the horizontal push rod applies a load to the sheet sample. During the measurement, set the pressure of the horizontal push rod contacting the sheet standard sample to 15-30 cN, and set the temperature to a heating rate of 3-5°C / min. The temperature is raised to each preset temperature in sequence to obtain a linear thermal expansion baseline of the sheet sample.

[0020] 4) Calculating the linear thermal expansion of the sheet sample based on the linear thermal expansion baseline of the sheet standard sample and the linear thermal expansion baseline of the sheet sample to obtain a linear thermal expansion coefficient curve of the sheet sample.

[0021] Furthermore, the process of obtaining the sheet sample is as follows:

[0022] The metal sheet to be tested is processed into a sheet sample with a length of 15 to 20 mm and a width of 5 to 7 mm by wire cutting;

[0023] Stack multiple sheet specimens neatly and glue them together, then polish and remove surface wire cutting marks to ensure that the length and width of each sheet specimen are consistent and flush.

[0024] The stacked samples after grinding and polishing are disassembled and placed in an ultrasonic cleaning machine to be cleaned with alcohol to remove surface impurities and glue. After cleaning and drying, multiple pieces are stacked flush to the standard sample thickness to obtain sheet samples.

[0025] Furthermore, the thickness of the sheet standard and the sheet sample does not exceed the width of the limiting groove along the radial direction perpendicular to the circular end face, and the width of the sheet standard and the sheet sample does not exceed the length of the limiting groove along the radial direction of the circular end face.

[0026] It can be seen from the above technical solutions that the technical solutions of the present invention have the following beneficial effects:

[0027] The present invention provides a sample detection device for a horizontal push rod dilatometer and an application method thereof, and relates to the field of expansion coefficient measurement of metal materials. The sample detection device is suitable for sheet samples and comprises a base and a fixing portion arranged on the base. The fixing portion comprises a pair of limiting structures arranged on one side of a horizontal push rod of the dilatometer and symmetrically and spaced apart along the axis of the horizontal push rod, wherein two side surfaces of the limiting structures close to each other are arranged as planes perpendicular to the axis of the horizontal push rod. If the plane is defined as a limiting surface, a pair of limiting grooves are symmetrically arranged on the two limiting surfaces, and the limiting grooves are used to mount a quadrilateral sheet sample arranged in a horizontal direction. The base is fixedly mounted in a sample holder of the dilatometer, and its contact surface with the limiting structure is smooth. The base ensures that the central axis of the sheet sample mounting position along the axis of the horizontal push rod coincides with the central axis of the horizontal push rod. When used, the sample detection device used in conjunction with the horizontal push rod, combined with a designed rectangular aluminum oxide standard sample having the same size as the sample, can ensure that the sheet sample can be stably tested, the sample is evenly stressed, and the linear thermal expansion coefficient test result is accurate.

[0028] Compared to existing technologies, the present invention improves the bending resistance and contact area of sheet samples by designing a sample detection device and a sheet standard, changing the sample size, and using laminated samples. This ensures that the dilatometer push rod can support and fix the sheet sample without deformation when the sample is subjected to force. This solves the problem of the dilatometer push rod being unable to support the sample due to the small force-bearing surface at the end of the sheet sample, resulting in sample slippage and bending under force, which makes testing impossible. This fully meets the requirements for linear thermal expansion coefficient testing of sheet samples. Furthermore, the sample detection device of the present invention has a simple structure and low cost. It can be installed in a conventional thermal dilatometer bracket for use, providing stable and reliable testing, reusable, and not easily damaged, thus saving testing costs.

[0029] It should be appreciated that all combinations of the foregoing concepts, as well as additional concepts described in greater detail below, to the extent such concepts are not mutually inconsistent, can be considered to be part of the inventive subject matter of this disclosure.

[0030] The foregoing and other aspects, embodiments, and features of the present invention will be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the present invention, such as features and / or beneficial effects of the exemplary embodiments, will become apparent from the following description or through practice of specific embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are not drawn to scale. In the accompanying drawings, each identical or nearly identical component shown in various figures may be represented by the same reference numeral. For clarity, not every component is labeled in every figure. Embodiments of various aspects of the present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0032] Figure 1 This is an exploded view of the sample detection device disclosed in the present invention;

[0033] Figure 2 It is a combined diagram of the sample detection device disclosed in the present invention;

[0034] Figure 3 The thermal expansion curve and thermal expansion coefficient curve of the sheet sample of Example 1 of the present invention;

[0035] Figure 4 The thermal expansion curve and thermal expansion coefficient curve of the sheet sample of Example 2 of the present invention;

[0036] In the figure, the specific meaning of each mark is:

[0037] 1-limiting structure, 1-1-limiting groove; 2-base, 2-1-mounting groove; 3-sheet sample; 4-horizontal push rod. DETAILED DESCRIPTION

[0038] To further clarify the objectives, technical solutions, and advantages of the embodiments of the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only a portion of the embodiments of the present invention, not all of them. Based on the described embodiments of the present invention, all other embodiments derived by persons of ordinary skill in the art without requiring creative effort are within the scope of protection of the present invention. Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meanings understood by persons of ordinary skill in the field to which the present invention pertains.

[0039] The words "first," "second," and similar terms used in the patent application specification and claims of the present invention do not indicate any order, quantity, or importance, but are only used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular forms of "a," "an," "the," and similar terms do not indicate a limit on quantity, but rather indicate the presence of at least one. Words such as "include" or "comprises" mean that the elements or objects preceding "include" or "comprises" include the features, wholes, steps, operations, elements, and / or components listed after "include" or "comprises," and do not exclude the existence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their collections.

[0040] Because sheet specimens are relatively thin and have a small end bearing surface, when using an existing horizontal push rod dilatometer to measure the linear thermal expansion coefficient, the horizontal push rod cannot accurately support the end of the sheet specimen. Therefore, the load cannot be accurately applied to the sheet specimen, resulting in failure of the sample slip test. In addition, because the sheet specimen is relatively thin, the horizontal push rod is likely to cause the sheet specimen to bend when it is applied, which can also lead to test failure. The present invention aims to provide a sample detection device for a horizontal push rod dilatometer and its application method. By designing a sample detection device suitable for sheet specimens, it ensures that the horizontal push rod can support and fix the sheet specimen during testing and prevents deformation after being subjected to force. This solves the problem that the push rod of the dilatometer cannot support the sample when the end bearing surface of the sheet specimen is small, resulting in sample slippage and sample bending under force, which makes it impossible to test. In combination with a standard sample, the linear thermal expansion coefficient of the sheet specimen can be accurately measured.

[0041] Combine Figure 1 and Figure 2 As shown, the sample detection device for a horizontal push rod dilatometer designed by the present invention is suitable for sheet samples and includes a base 2 and a fixing portion provided on the base 1; as shown in the figure, the fixing portion includes a pair of limiting structures 1, the limiting structures 1 being provided on one side of a horizontal push rod 4 of the horizontal push rod dilatometer, and the limiting structures 1 being axially symmetrical along the horizontal push rod 4 and spaced apart on the base 2; the two side surfaces of the limiting structures 1 on the base 2 that are close to each other are configured as planes, and the planes are perpendicular to the axial direction of the horizontal push rod 4;

[0042] The planes on which the upper limit structures 1 of the base 2 are close to each other are defined as the limiting surfaces. A pair of limiting grooves 1-1 are symmetrically provided on the two limiting surfaces. The limiting grooves 1-1 form a sheet sample mounting position. The sheet sample mounting position is used to mount a quadrilateral sheet sample 3. When the sheet sample 3 is placed in the sheet sample mounting position, the sheet sample 3 is arranged in a horizontal direction and is perpendicular to the limiting surfaces.

[0043] The base 2 is fixedly mounted within the sample holder of the horizontal push rod dilatometer. The contact surface between the base 2 and the limiting structure 1 is smooth, and the base 2 ensures that the central axis of the sheet sample mounting position along the axial direction of the horizontal push rod 4 coincides with the central axis of the horizontal push rod 4. Ensuring that the central axis of the sheet sample mounting position along the axial direction of the horizontal push rod 4 coincides with the central axis of the horizontal push rod 4 ensures that the horizontal push rod of the dilatometer can support and secure the sheet sample and accurately apply the load to the sheet sample.

[0044] In the embodiment, the sheet sample 3 is fixed between two limiting structures 1. Therefore, in order to accurately detect the thermal deformation of the sheet sample 3 in the dilatometer, the relative positional relationship between the limiting structures should be as free as possible from interference from other external factors, such as the friction resistance between the limiting structure 1 and the base 2 when the limiting structure 1 moves. Therefore, when designing the sample detection device, a mounting groove 2-1 is provided on the side of the base 2 close to the fixed part. The groove surface of the mounting groove 2-1 is smooth, and the limiting structure 1 is adapted to be engaged in the mounting groove 2-1. By reducing the friction between the limiting structure 1 and the base 2, the measurement error of the linear thermal expansion coefficient caused by the movement of the limiting structure 1 is reduced.

[0045] Combine Figure 1 and Figure 2 In the specific embodiment shown, the limiting structure 1 is configured as a cylindrical structure coaxial with the horizontal push rod 4, such as a circular pad having a certain thickness. The limiting groove 1-1 is provided on the circular end face of the cylindrical structure, and the limiting grooves 1-1 are centrally symmetrically distributed along the radial direction of the circular end face. In order to allow the sheet sample 3 to be arranged horizontally when fixed and to stably fix the sheet sample 3, the limiting groove 1-1 is provided on the circular end face and extends horizontally through the center of the circle. The limiting groove 1-1 is configured as a rectangular groove. The depth of the rectangular groove along the axial direction of the horizontal push rod 4 is 0.5 to 1 mm, the length along the radial direction of the circular end face is 5.5 to 7.5 mm, and the width perpendicular to the radial direction of the circular end face is 2.5 to 5 mm.

[0046] The base 2 in the sample detection device is designed as follows: it includes a pair of support seats arranged symmetrically and spaced apart along the axis of the horizontal push rod 4, and an arc groove is provided on one side of any of the support seats close to the limiting structure 1; the axial direction of the arc groove is parallel to the axial direction of the horizontal push rod 4, the size of the arc groove is adapted to the outer wall size of the limiting structure 1, and the roughness R of the arc groove surface is a In the embodiment, a side surface of the support base close to and in contact with the sample holder is configured as a polygonal side surface inscribed in the inner wall surface of the sample holder, and the support base is adapted to engage with the inner wall surface of the sample holder during installation.

[0047] In the embodiment, the base 2 and the fixing portion are both made of aluminum oxide.

[0048] The present invention further provides an application method of the sample detection device for the horizontal push rod dilatometer, which specifically comprises the following steps:

[0049] 1) Obtaining a sheet standard and a sheet sample, wherein the sheet standard is an aluminum oxide sheet having a thickness of 2-4 mm, a length of 15-20 mm, and a width of 5-7 mm, wherein the purity of the aluminum oxide in the aluminum oxide sheet is not less than 99.9%, and the dimensional accuracy of the sheet in the longitudinal direction does not exceed 0.02%; the sheet sample is the same size as the sheet standard and is composed of multiple neatly stacked metal sheets to be tested; wherein the thickness of the sheet standard and the sheet sample does not exceed the width of the limiting groove along a radial direction perpendicular to the circular end face, and the width of the sheet standard and the sheet sample does not exceed the length of the limiting groove along the radial direction of the circular end face;

[0050] Optionally, the process of obtaining the sheet sample is as follows: the metal sheet to be tested is processed into a sheet sample with a length of 15 to 20 mm and a width of 5 to 7 mm by wire cutting; multiple sheet samples are neatly stacked and fixed with glue, and then the samples are polished to remove the surface wire cutting marks to ensure that the length and width of each sheet sample are consistent and flush; the stacked samples after polishing are disassembled and placed in an ultrasonic cleaning machine for cleaning with alcohol to remove surface impurities and glue, and after cleaning and drying, multiple sheets are stacked flush to the standard sample thickness to obtain sheet samples.

[0051] 2) Measuring the length of the sheet standard sample, after which the sheet standard sample is horizontally mounted in a pair of limiting grooves of a limiting structure in a sample detection device, and then placing the sample detection device into a sample holder of a horizontal push rod dilatometer. After securing the sample, the horizontal push rod applies a load to the sheet standard sample. During the measurement, the pressure of the horizontal push rod contacting the sheet standard sample is set to 15 to 30 cN, and the temperature is raised at a rate of 3 to 5°C / min to each preset temperature, thereby obtaining a linear thermal expansion baseline of the sheet standard sample.

[0052] 3) Measure the length of the sheet sample. After the measurement, horizontally install the sheet sample in a pair of limiting grooves of the limiting structure of the sample detection device. Then, place the sample detection device in the sample holder of the horizontal push rod dilatometer. After fixing, the horizontal push rod applies a load to the sheet sample. During the measurement, set the pressure of the horizontal push rod contacting the sheet standard sample to 15-30 cN, and set the temperature to a heating rate of 3-5°C / min. The temperature is raised to each preset temperature in sequence to obtain a linear thermal expansion baseline of the sheet sample.

[0053] 4) calculating the linear thermal expansion of the sheet sample based on the linear thermal expansion baseline of the sheet standard sample and the linear thermal expansion baseline of the sheet sample to obtain a linear thermal expansion coefficient curve of the sheet sample;

[0054] Specifically, the linear thermal expansion value of the sheet sample is calculated using the following formula: ΔL / L0=(ΔL / L0) t -(ΔL / L0) m +(ΔL / L0) α, according to the linear thermal expansion values at different temperatures, a linear thermal expansion curve is drawn, and the linear thermal expansion coefficient curve can be calculated based on the linear thermal expansion curve; where ΔL / L0 is the linear thermal expansion value of the sheet sample, (ΔL / L0) t is the theoretical linear thermal expansion value of the sheet standard; (ΔL / L0) m is the linear thermal expansion value of the sheet standard sample measured by the horizontal push rod dilatometer, (ΔL / L0) α It is the linear thermal expansion value of the sheet sample measured by the horizontal push rod dilatometer.

[0055] The sample detection device for a horizontal push rod dilatometer disclosed in the present invention and its application method will be further described in detail below with reference to specific embodiments.

[0056] Example 1

[0057] (1) Place the support base and the limiting structure 1 of the detection device horizontally into the sample holder of the thermal expansion instrument (the support base and the limiting structure 1 need to be used in pairs, with one placed on each side at an interval of about 15 mm). Then, install the prepared rectangular aluminum oxide sheet standard (length 15 mm × width 5 mm × thickness 2 mm) into the limiting groove 1-1 of the limiting structure 1. Adjust the position so that the sheet standard is placed horizontally with the wide side facing upward. Move the horizontal push rod 4 of the expansion instrument to the limiting structure 1, and the limiting groove 1-1 to the sheet standard. The support base supports the limiting structure 1. Adjust the horizontal push rod 4 to connect The pressure of the contact sheet standard is 15 cN, and the sheet standard is fixed by the interaction of the horizontal push rod 4, the limiting structure 1, the limiting groove 1-1 and the support base. The software temperature program of the dilatometer is set, with argon purge, a gas flow rate of 150 ml / min, and a heating rate of 3°C / min. The temperature is sequentially raised to various preset temperatures, such as 100°C, 200°C, 300°C, 400°C, 500°C, and 600°C. The linear thermal expansion results of the sheet standard during the heating process are recorded using a correction mode to obtain a linear thermal expansion baseline file of the aluminum oxide sheet standard.

[0058] (2) The prepared sheet sample 3 with a thickness of about 2 mm is placed into the limiting groove 1-1 of the limiting structure 1. The sheet sample 3 is made of 8 metal sheets with a length of 15 mm, a width of 5 mm, and a thickness of 0.25 mm, which are stacked flatly. The metal sheets are selected from silicon steel with a brand name of SG50WV1300. The position is adjusted so that the sheet sample 3 is placed horizontally with the wide side facing upwards. The horizontal push rod 4 of the dilatometer is moved to press against the limiting structure 1, and the limiting groove 1-1 presses against the sheet sample 3. The support seat supports the limiting structure 1. The pressure of the horizontal push rod 4 contacting the sheet sample 3 is adjusted to 15 cN. The sheet sample 3 is fixed by the interaction of the horizontal push rod 4, the limiting structure 1, the limiting groove 1-1, and the support seat. The linear thermal expansion baseline file of the aluminum oxide sheet standard is opened, and the sample + correction mode is selected to record the linear thermal expansion results of the sheet sample 3 during the heating process. The linear thermal expansion curve of the sheet sample 3 and the average linear expansion coefficient curve at different temperatures are obtained, as shown in FIG. Figure 3 shown.

[0059] Example 2

[0060] (1) Place the support base and the limiting structure 1 of the detection device horizontally into the sample holder of the thermal expansion instrument (the support base and the limiting structure 1 need to be used in pairs, with one placed on each side at an interval of about 20 mm). Then, install the prepared rectangular aluminum oxide sheet standard (length 20 mm × width 6 mm × thickness 4 mm) into the limiting groove 1-1 of the limiting structure 1. Adjust the position so that the sheet standard is placed horizontally with the wide side facing upward. Move the horizontal push rod 4 of the expansion instrument to the limiting structure 1. The limiting groove 1-1 supports the sheet standard. The support base supports the limiting structure 1. Adjust the horizontal push rod 4 to contact The pressure of the sheet standard sample is 30 cN, and the sheet standard sample is fixed by the interaction of the horizontal push rod 4, the limiting structure 1, the limiting groove 1-1 and the support base. The software temperature program of the dilatometer is set, with argon purge, a gas flow rate of 150 ml / min, and a heating rate of 5°C / min. The temperature is sequentially raised to various preset temperatures, such as 100°C, 200°C, 300°C, 400°C, 500°C, and 600°C. The linear thermal expansion results of the sheet standard sample during the heating process are recorded using a correction mode to obtain a linear thermal expansion baseline file of the aluminum oxide sheet standard sample.

[0061] (2) The prepared sheet sample 3 with a thickness of about 4 mm is placed into the limiting groove 1-1 of the limiting structure 1. The sheet sample 3 is made of 8 metal sheets with a length of 20 mm, a width of 6 mm, and a thickness of 0.5 mm, which are stacked flatly. The metal sheets are selected from silicon steel with a grade of SG50WV1300. The position is adjusted so that the sheet sample 3 is placed horizontally with the wide side facing upwards. The horizontal push rod 4 of the dilatometer is moved to press against the limiting structure 1, and the limiting groove 1-1 presses against the sheet sample 3. The support seat supports the limiting structure 1. The pressure of the horizontal push rod 4 contacting the sheet sample 3 is adjusted to 30 cN. The sheet sample 3 is fixed by the interaction of the horizontal push rod 4, the limiting structure 1, the limiting groove 1-1, and the support seat. The linear thermal expansion baseline file of the aluminum oxide sheet standard is opened, and the sample + correction mode is selected to record the linear thermal expansion results of the sheet sample 3 during the heating process. The linear thermal expansion curve of the sheet sample 3 and the average linear expansion coefficient curve at different temperatures are obtained, as shown in FIG. Figure 4 shown.

[0062] Example 3

[0063] (1) Place the support base and the limiting structure 1 of the detection device horizontally into the sample holder of the thermal expansion instrument (the support base and the limiting structure 1 need to be used in pairs, with one placed on each side at an interval of about 20 mm). Then, install the prepared rectangular aluminum oxide sheet standard (length 20 mm × width 6 mm × thickness 4 mm) into the limiting groove 1-1 of the limiting structure 1. Adjust the position so that the sheet standard is placed horizontally with the wide side facing upward. Move the horizontal push rod 4 of the expansion instrument to the limiting structure 1, and the limiting groove 1-1 to the sheet standard. The support base supports the limiting structure 1. Adjust the horizontal push rod 4 to connect The pressure of the contact sheet standard is 30 cN, and the sheet standard is fixed by the interaction of the horizontal push rod 4, the limiting structure 1, the limiting groove 1-1 and the support base. The software temperature program of the dilatometer is set, with argon purge, a gas flow rate of 150 ml / min, and a heating rate of 5°C / min. The temperature is sequentially raised to various preset temperatures, such as 100°C, 200°C, 300°C, 400°C, 500°C, and 600°C. The linear thermal expansion results of the sheet standard during the heating process are recorded using a correction mode to obtain a linear thermal expansion baseline file of the aluminum oxide sheet standard.

[0064] (2) The sheet standard sample was used as the sheet sample 3 for testing. The baseline file of the sheet standard sample was opened. The sample + correction mode was selected to record the linear thermal expansion results of the sample during the heating process. The measured linear thermal expansion curve of the sheet standard sample was obtained. The test results are shown in Table 1 below.

[0065] Table 1 Linear thermal expansion values of rectangular aluminum oxide standard samples measured in the dilatometer

[0066]

[0067] As shown in Table 1, after the sheet standard sample was installed as a sample in the sample detection device proposed in the present invention and the linear thermal expansion value was measured using a horizontal push rod dilatometer, it can be seen that the comparison error between the theoretical value and the measured value of the linear thermal expansion value of the sheet standard sample in Example 3 is within 3%, which shows that the measurement results have good consistency and accuracy. It also fully demonstrates that the test method of the present invention is stable and reliable for the linear thermal expansion value test results of the sheet samples in Examples 1 and 2, and furthermore, the linear thermal expansion coefficient curve data calculated for each sheet sample 3 is stable and reliable.

[0068] In summary, the sample detection device for the horizontal push rod dilatometer proposed in the present invention, when used in conjunction with the proposed application method, can measure the linear thermal expansion coefficient of sheet samples with high accuracy. This fully solves the problem that existing horizontal push rod dilatometers can only measure cylindrical samples of a target thickness, thereby expanding the measurement range of the horizontal push rod dilatometer.

[0069] While the present invention has been disclosed above with reference to preferred embodiments, this is not intended to limit the present invention. Persons skilled in the art will readily appreciate that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A sample detection device for a horizontal push rod dilatometer, characterized in that: Suitable for sheet samples, comprising a base and a fixing portion arranged on the base; The fixing portion includes a pair of limiting structures, the limiting structures are arranged on one side of the horizontal push rod of the horizontal push rod dilatometer, and the limiting structures are symmetrical along the axis of the horizontal push rod and are arranged on the base at intervals; the two side surfaces of the limiting structures on the base that are close to each other are set as planes, and the planes are perpendicular to the axis of the horizontal push rod; The planes where the upper limit structures of the base are close to each other are defined as the limiting surfaces, and a pair of limiting grooves are symmetrically provided on the two limiting surfaces, and the limiting grooves form a sheet sample mounting position; the sheet sample mounting position is used to mount a quadrilateral sheet sample, and when the sheet sample is placed in the sheet sample mounting position, the sheet sample is arranged in a horizontal direction and is perpendicular to the limiting surfaces; The base is fixed in the sample holder of the horizontal push rod dilatometer, the contact surface of the base with the limiting structure is smooth, and the base makes the central axis of the sheet sample installation position along the axial direction of the horizontal push rod coincide with the central axis of the horizontal push rod.

2. The sample detection device for a horizontal push rod dilatometer according to claim 1, characterized in that: A mounting groove is provided on a side of the base close to the fixing portion, the groove surface of the mounting groove is smooth, and the limiting structure is adapted to be engaged in the mounting groove.

3. The sample detection device for a horizontal push rod dilatometer according to claim 1, characterized in that: The limiting structure is configured as a cylindrical structure coaxial with the horizontal push rod, the limiting grooves are configured on the circular end surface of the cylindrical structure, and the limiting grooves are centrally symmetrically distributed along the radial direction of the circular end surface.

4. The sample detection device for a horizontal push rod dilatometer according to claim 3, characterized in that: The limiting groove is configured as a rectangular groove, the depth of which along the axial direction of the horizontal push rod is 0.5 to 1 mm, the length along the radial direction of the circular end face is 5.5 to 7.5 mm, and the width along the radial direction perpendicular to the circular end face is 2.5 to 5 mm.

5. The sample detection device for a horizontal push rod dilatometer according to claim 3, characterized in that: The base includes a pair of support seats that are symmetrical and spaced apart along the axis of the horizontal push rod. An arc groove is provided on the side of any support seat close to the limiting structure. The axial direction of the arc groove is parallel to the axial direction of the horizontal push rod, and the size of the arc groove is adapted to the outer wall size of the limiting structure.

6. The sample detection device for a horizontal push rod dilatometer according to claim 5, characterized in that: The roughness R of the arc groove surface a Not exceeding 0.8μm.

7. The sample detection device for a horizontal push rod dilatometer according to claim 1, characterized in that: The base and the fixing portion are both made of aluminum oxide.

8. A method for using the sample detection device for a horizontal push rod dilatometer according to any one of claims 1 to 7, characterized in that: The steps include: 1) Obtaining a standard sheet and a sheet sample; wherein the standard sheet is an aluminum oxide sheet having a thickness of 2 to 4 mm, a length of 15 to 20 mm, and a width of 5 to 7 mm, wherein the aluminum oxide purity of the aluminum oxide sheet is not less than 99.9% and the dimensional accuracy of the aluminum oxide sheet in the longitudinal direction does not exceed 0.02%; the sheet sample has the same dimensions as the standard sheet and is composed of multiple neatly stacked metal sheets to be tested; 2) Measuring the length of the sheet standard sample, after which the sheet standard sample is horizontally mounted in a pair of limiting grooves of a limiting structure in a sample detection device, and then placing the sample detection device into a sample holder of a horizontal push rod dilatometer. After securing the sample, the horizontal push rod applies a load to the sheet standard sample. During the measurement, the pressure of the horizontal push rod contacting the sheet standard sample is set to 15 to 30 cN, and the temperature is raised at a rate of 3 to 5°C / min to each preset temperature, thereby obtaining a linear thermal expansion baseline of the sheet standard sample. 3) Measure the length of the sheet sample. After the measurement, horizontally install the sheet sample in a pair of limiting grooves of the limiting structure of the sample detection device. Then, place the sample detection device in the sample holder of the horizontal push rod dilatometer. After fixing, the horizontal push rod applies a load to the sheet sample. During the measurement, set the pressure of the horizontal push rod contacting the sheet standard sample to 15-30 cN, and set the temperature to a heating rate of 3-5°C / min. The temperature is raised to each preset temperature in sequence to obtain a linear thermal expansion baseline of the sheet sample. 4) Calculating the linear thermal expansion of the sheet sample based on the linear thermal expansion baseline of the sheet standard sample and the linear thermal expansion baseline of the sheet sample to obtain a linear thermal expansion coefficient curve of the sheet sample.

9. The method for using the sample detection device for the horizontal push rod dilatometer according to claim 8, characterized in that: The process of obtaining the sheet sample is as follows: The metal sheet to be tested is processed into a sheet sample with a length of 15 to 20 mm and a width of 5 to 7 mm by wire cutting; Stack multiple sheet specimens neatly and glue them together, then polish and remove surface wire cutting marks to ensure that the length and width of each sheet specimen are consistent and flush. The stacked samples after grinding and polishing are disassembled and placed in an ultrasonic cleaning machine to be cleaned with alcohol to remove surface impurities and glue. After cleaning and drying, multiple pieces are stacked flush to the standard sample thickness to obtain sheet samples.

10. The method for using the sample detection device for a horizontal push rod dilatometer according to claim 8, characterized in that: The thickness of the sheet standard and the sheet sample does not exceed the width of the limiting groove along the radial direction perpendicular to the circular end face, and the width of the sheet standard and the sheet sample does not exceed the length of the limiting groove along the radial direction of the circular end face.

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