Jig for testing static bending strength of ceramic

Abstract

The utility model discloses a fixture for testing static bending strength of ceramic, which comprises a pressure head, a support and a base, the pressure head is positioned above the support, and the support is connected with the base below the support; a limiting groove is formed in the inner side of the bracket, and a sample bridged on the bracket is limited and fixed through the limiting groove; the groove bottom of the limiting groove and the extension of the inner side wall of the support form a second R-shaped angle smaller than 90 degrees, and at least one side face of the base is engraved with scale marks; and the protective jacket of the jig is matched with the bracket. The device is simple in overall structure and convenient to operate, and the testing efficiency can be effectively improved; due to the design of the limiting groove, the test sample is not prone to slipping during testing, the fixing effect is better, and measurement fluctuation is effectively reduced; the design of the protective jacket can effectively prevent a broken sample from splashing to hurt people and prevent personal injury; the design of the R-shaped angle is beneficial for improving the stability of a test result and can prevent fracture from occurring on a crossing point at the two ends of the load.

Description

Technical Field

[0001] This utility model relates to the technical field of ceramic material performance testing devices, and in particular to a fixture for testing the static bending strength of ceramics. Background Technology

[0002] Flexural strength, or bending strength, is a primary indicator used to measure the mechanical properties of ceramic materials. The bending strength of ceramics depends on its inherent resistance to fracture and the characteristics of the ceramic itself. Testing methods for ceramic bending strength include four-point bending and three-point bending. Because of its simple structure and ease of use in high-temperature experiments and fracture toughness tests, three-point bending is more commonly used in the field of fine ceramics.

[0003] Currently, several national standards specify testing equipment for the flexural strength of ceramic materials, but there are few regulations or descriptions regarding testing fixtures. The national standard GB / T 4741-1999, "Test Method for Bending Strength of Ceramic Materials," only specifies a bending strength testing machine as the testing equipment for determining the room temperature flexural strength of ceramic materials using the three-point load method, but does not specify requirements for testing fixtures. The national standard GB / T 11387-2008, "Test Method for Performance of Piezoelectric Ceramic Materials—Test for Static Bending Strength," only specifies the material properties, radius of curvature, and roughness of the support and indenter of the static bending strength testing fixture for ceramic materials, without describing the structure of the testing fixture.

[0004] The standard "HG 2-164-65 Test Method for Static Bending Strength of Plastics" only provides a simplified structural diagram of the test fixture, which consists of a pressure head with a semi-circular contact point and a pair of supports with rounded contact points. However, when using this fixture to test bending strength, the following problems may occur during use: (1) sample slippage affects measurement accuracy, and (2) sample breakage and splashing can cause injury.

[0005] Chinese patent document CN21459031U provides a three-point bending strength test fixture for ceramic materials. To solve the problem of inaccurate positioning of ceramic test blocks on the test fixture, which affects the accuracy of test results, a limiting groove assembly is provided to limit and fix three test rods. A fixture outer sleeve is provided to prevent broken sample blocks or debris from splashing and to improve operational safety. However, this fixture consists of more than 5 parts, has a complex structure, and is difficult to process. Utility Model Content

[0006] To address the shortcomings of existing technologies, this invention provides a fixture for testing the static bending strength of ceramics, which solves the problems of poor sample fixation and sample splashing that could cause injury.

[0007] To achieve the above objectives, this utility model provides the following solution:

[0008] A fixture for testing the static bending strength of ceramics includes an indenter, a support, and a base. The indenter is located above the support, which is connected to the base below it. A limiting groove is formed on the inner side of the support to limit and fix the sample bridging the support. The bottom of the limiting groove and the outer extension of the inner wall of the support form a second R-shaped angle of less than 90°. At least one side of the base is engraved with scale graduations. The fixture also includes a protective sleeve that matches the support.

[0009] Preferably, the head of the pressure head has a first R-shaped angle with a radius of 1mm to 10mm.

[0010] Preferably, the height of the limiting groove is 1mm to 10mm.

[0011] Preferably, the height of the limiting groove is 2mm to 5mm.

[0012] Preferably, the angle of the second R-shaped angle is 45°~85° and the radius is 1mm~10mm.

[0013] Preferably, the pressure head and the bracket are made of hardened stainless steel or carbon steel.

[0014] Compared with the closest existing technology, the technical solution provided by this utility model has the following beneficial effects:

[0015] The design of the limiting groove in this invention makes the test sample less prone to slipping during testing, resulting in better fixation and effectively reducing measurement fluctuations. The protective jacket design effectively prevents broken test samples from splashing and injuring people. The R-shaped angle design ensures that the direction of the load force is the same as the diameter direction of the R-angle, which helps to improve the stability of the test results. In addition, the R-shaped angle can also avoid the influence of sharp right angles on the load, causing scratches and cracks, and prevent the breakage from occurring at the bridging points at both ends of the load. In summary, this invention has a simple overall structure, is easy to operate, and can effectively improve the efficiency of testing. Attached Figure Description

[0016] Figure 1 This utility model discloses a front view of the overall structure of a fixture for testing the static bending strength of ceramics;

[0017] Figure 2 A perspective view of the bracket of this utility model;

[0018] Figure 3 A cross-sectional view of the bracket of this utility model;

[0019] Explanation of reference numerals in the attached drawings: 1. Pressure head, 11. First R-shaped angle, 2. Bracket, 21. Limiting groove, 22. Second R-shaped angle, 3. Base, 4. Protective cover. Detailed Implementation

[0020] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0021] This utility model provides the following technical solution:

[0022] Example 1

[0023] A fixture for testing the static bending strength of ceramics includes an indenter, a support, and a base. The support comprises two parts, left and right, with limiting grooves formed on their opposing inner sides to limit the position of the sample bridging the support. The head of the indenter has a first R-shaped angle with a radius of 1 mm to 10 mm. The height of the limiting groove is 1 mm to 10 mm, and the bottom of the limiting groove and the outer extension of the inner wall of the support form a second R-shaped angle of 45° to 85° with a radius of 1 mm to 10 mm.

[0024] ① Compared to a right angle, an R-angle ensures that the direction of the load is the same as the direction of the R-angle diameter, which helps improve the stability of the test results.

[0025] ② The load is generally a long ceramic strip, and the fracture point should be in the middle area, near the contact area of ​​the indenter. Due to the brittleness of ceramics, micro-cracks or points of concentrated stress are often the initiation points of fracture. The R-shaped angle can avoid the impact of sharp right angles on the load, causing dents and cracks, and prevent the fracture from occurring at the bridging points at both ends.

[0026] Furthermore, at least one side of the base is engraved with scale markings. The scale markings on the side of the base facilitate adjustment of the span support spacing and make it easy to read the span parameters.

[0027] Furthermore, the fixture also includes a protective cover that matches the support. The protective cover covers the space where the test ceramic strips may splash out, protecting the operator's personal safety and facilitating the collection of the tested ceramic strips.

[0028] Furthermore, the indenter and support are made of hardened stainless steel or carbon steel. The indenter and support directly contact the ceramic sample strip being tested; the high-strength material helps reduce the deformation of the fixture and improves the accuracy of the test results.

[0029] Example 2

[0030] A fixture for testing the static bending strength of ceramics includes an indenter, a support, and a base. The support comprises two parts, left and right, with limiting grooves on their opposing inner sides to limit the movement of the sample spanning the support. The indenter's head has a first R-shaped angle with a radius of 1 mm. The limiting groove has a height of 1 mm, and the bottom of the limiting groove forms a second R-shaped angle with a radius of 1 mm and a 45° angle with the outer extension of the inner wall of the support. The indenter and support are made of hardened stainless steel. A scale is engraved on one side of the base. The scale on the side of the base facilitates adjustment of the span support spacing and easy reading of span parameters. The fixture also includes a protective sleeve that mates with the support.

[0031] Example 3

[0032] A fixture for testing the static bending strength of ceramics includes an indenter, a support, and a base. The support comprises two parts, left and right, with limiting grooves on their opposing inner sides to limit the movement of the sample spanning the support. The indenter's head has a first R-shaped angle with a radius of 2 mm. The limiting groove has a height of 2 mm, and the bottom of the limiting groove forms a second R-shaped angle with a radius of 2 mm and a 60° angle with the outer extension of the inner wall of the support. The indenter and support are made of carbon steel. The base has scale markings on both sides. These scale markings on the base side facilitate adjustment of the span support spacing and easy reading of span parameters. The fixture also includes a protective sleeve that mates with the support.

[0033] Example 4

[0034] A fixture for testing the static bending strength of ceramics includes an indenter, a support, and a base. The support comprises two parts, left and right, with limiting grooves on their opposing inner sides to limit the movement of the sample spanning the support. The indenter's head has a first R-shaped angle with a radius of 5mm. The limiting groove has a height of 5mm, and the bottom of the limiting groove forms a second R-shaped angle with a radius of 5mm at 75° with the outer extension of the inner wall of the support. The indenter and support are made of hardened stainless steel. A scale is engraved on one side of the base. The scale on the base side facilitates adjustment of the span support spacing and easy reading of span parameters. The fixture also includes a protective sleeve that mates with the support.

[0035] Example 5

[0036] A fixture for testing the static bending strength of ceramics includes an indenter, a support, and a base. The support comprises two parts, left and right, with limiting grooves on their opposing inner sides to limit the movement of the sample spanning the support. The indenter's head has a first R-shaped angle with a radius of 8 mm. The limiting groove has a height of 8 mm, and the bottom of the limiting groove forms a second R-shaped angle with an 85° angle and a radius of 8 mm with the outer extension of the inner wall of the support. The indenter and support are made of hardened stainless steel. The base has scale markings on both sides. These scale markings on the base side facilitate adjustment of the span support spacing and easy reading of span parameters. The fixture also includes a protective sleeve that mates with the support.

[0037] Example 6

[0038] A fixture for testing the static bending strength of ceramics includes an indenter, a support, and a base. The support comprises two parts, left and right, with limiting grooves on their opposing inner sides to limit the movement of the sample spanning the support. The indenter's head has a first R-shaped angle with a radius of 10 mm. The limiting groove has a height of 10 mm, and the bottom of the limiting groove forms a second R-shaped angle with an 85° angle and a radius of 10 mm with the outer extension of the inner wall of the support. The indenter and support are made of carbon steel. A scale is engraved on one side of the base. The scale on the base side facilitates adjustment of the span support spacing and easy reading of span parameters. The fixture also includes a protective sleeve that mates with the support.

[0039] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A fixture for testing the static bending strength of ceramics, comprising an indenter (1), a support (2), and a base (3), characterized in that: The pressure head (1) is located above the support (2), and the support (2) is connected to the base (3) below it; a limiting groove (21) is opened on the inner side of the support (2), and the sample connected to the support (2) is limited and fixed by the limiting groove (21); the bottom of the limiting groove (21) and the inner sidewall of the support (2) form a second R-shaped angle (22) of less than 90°; at least one side of the base (3) is engraved with a scale; the fixture also includes a protective cover (4), which matches the support (2).

2. The fixture for testing the static bending strength of ceramics according to claim 1, characterized in that, The head of the pressure head (1) is a first R-shaped angle (11) with a radius of 1mm to 10mm.

3. The fixture for testing the static bending strength of ceramics according to claim 1, characterized in that, The height of the limiting groove (21) is 1mm~10mm.

4. A fixture for testing the static bending strength of ceramics according to claim 3, characterized in that, The height of the limiting groove (21) is 2mm~5mm.

5. A fixture for testing the static bending strength of ceramics according to claim 1, characterized in that, The angle of the second R-shaped angle (22) is 45°~85° and the radius is 1mm~10mm.

6. A fixture for testing the static bending strength of ceramics according to claim 1, characterized in that, The pressure head (1) and the bracket (2) are made of hardened stainless steel or carbon steel.

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