CN-224231450-U - Preparation and monitoring device suitable for multi-size fracture toughness sample prefabricated crack

Abstract

The utility model provides a preparation and monitoring device suitable for a multi-size fracture toughness sample prefabricated crack. The preparation and monitoring device suitable for the multi-size fracture toughness sample prefabricated cracks comprises two clamps which are symmetrically arranged, two support rollers are symmetrically arranged on the clamps, the same support rollers are arranged between the support rollers, two ends of each support pin extend into the support rollers respectively, two support pins are provided with the same sample to be tested, and one side of the sample to be tested is provided with a stress sheet. The preparation and monitoring device suitable for the multi-size fracture toughness sample prefabricated cracks has the advantages of being suitable for fracture toughness test tools with various sizes, monitoring crack length by a strain monitoring method, and reducing high-frequency use of a COD gauge.

Inventors

• ZHAO SHUO
• WANG JUE
• BAI TAO
• HU ZHIBO
• LI MINGXING
• ZHAO LI
• ZHAO HANPENG
• WANG YUGUANG
• REN GUOQIANG
• WANG YANHUA
• GUO ZECE

Assignees

• 中国铁道科学研究院集团有限公司
• 中国铁道科学研究院集团有限公司标准计量研究所

Dates

Publication Date

20260512

Application Date

20250529

Claims (5)

1. 1. A device for preparing and monitoring a crack in a specimen preform suitable for multi-dimensional fracture toughness, comprising: The two symmetrical clamps are symmetrically provided with two supporting rollers, the same supporting rollers are arranged between the two supporting rollers, two ends of each loading pin extend into the supporting rollers respectively, two loading pins are provided with the same sample to be tested, and one side of the sample to be tested is provided with a stress sheet.
2. 2. The apparatus for preparing and monitoring a crack as set forth in claim 1, further comprising a dynamic strain gauge coupled to the stress flake.
3. 3. The device for preparing and monitoring the pre-cracks of the multi-size fracture toughness test sample according to claim 1, wherein positioning gaskets are arranged on two sides of the clamp, and the positioning gaskets are in contact with the supporting rollers.
4. 4. The device for preparing and monitoring the pre-cracks of the multi-size fracture toughness test pieces according to claim 3, wherein the screws are arranged on two sides of the clamp, and penetrate through the corresponding positioning gaskets.
5. 5. The device for preparing and monitoring the pre-cracks of the multi-size fracture toughness test sample according to claim 1, wherein a plurality of mounting grooves are formed in one side of the supporting roller, and the apertures of the plurality of mounting grooves are different.

Description

Preparation and monitoring device suitable for multi-size fracture toughness sample prefabricated crack Technical Field The utility model relates to the technical field of fracture toughness monitoring, in particular to a preparation and monitoring device suitable for multi-size fracture toughness sample prefabricated cracks. Background Fracture toughness is one of the important mechanical properties of metals, which reflects the resistance of a metallic material to crack propagation. The prefabricated fatigue crack is a very important step in fracture toughness test, however, in practical operation, the length of the prefabricated fatigue crack is difficult to observe, a method for calculating the length of the fatigue crack by using the opening amount of a COD gauge is specified in ASTM E399, however, the COD gauge is extremely fragile under long-time high-frequency fatigue load, and in the test process of some small-size samples, the COD gauge is difficult to match with the samples, so that a more proper method is needed for monitoring the generation and the expansion of the crack. In addition, in different product standards, fracture toughness samples are different in size and correspond to a plurality of different tools, so that the test efficiency is reduced while the test space is occupied. Therefore, there is a need to provide a new device for preparing and monitoring the prefabricated cracks of the multi-size fracture toughness test sample, which solves the above technical problems. Disclosure of utility model The utility model solves the technical problem of providing a preparation and monitoring device which is suitable for fracture toughness test tools with various sizes, monitors crack length by a method of monitoring strain, reduces high-frequency use of COD gauges and is suitable for prefabrication cracks of fracture toughness samples with various sizes. In order to solve the technical problems, the preparation and monitoring device suitable for the multi-size fracture toughness sample prefabrication cracks comprises two symmetrically arranged clamps 1, wherein two supporting rollers 2 are symmetrically arranged on the clamps 1, one loading pin 3 is arranged between the same supporting rollers 2, two ends of the loading pin 3 extend into the supporting rollers 2 respectively, one sample 6 to be tested is arranged on the two loading pins 3, and a stress sheet 5 is arranged on one side of the sample 6 to be tested. Preferably, a dynamic strain gauge 7 is further included, and the dynamic strain gauge 7 is connected with the stress sheet 5. Preferably, positioning gaskets 4 are arranged on two sides of the clamp 1, and the positioning gaskets 4 are in contact with the supporting roller 2. Preferably, screws are arranged on both sides of the clamp 1, and penetrate through the corresponding positioning gaskets 4. Preferably, a plurality of mounting grooves are formed in one side of the support roller 2, and the apertures of the plurality of mounting grooves are different. Compared with the related art, the preparation and monitoring device suitable for the multi-size fracture toughness sample pre-cracking has the following beneficial effects: The utility model provides a preparation and monitoring device suitable for multi-size fracture toughness sample prefabricated cracks, which can be used for improving the applicability of the whole device by arranging loading pins 3 with different diameters according to different samples 6 to be tested through a supporting roller 2, limiting the supporting roller 2 through the arrangement of a positioning gasket 4 so as to ensure that the supporting roller 2 cannot slide down in the test process, and monitoring a strain curve of the bottom center of the sample through a strain gauge 5 and a dynamic strain gauge 7. Drawings FIG. 1 is a schematic cross-sectional view of a preferred embodiment of a device for preparing and monitoring a crack in a multi-dimensional fracture toughness test specimen according to the present utility model; FIG. 2 is a schematic side view of the structure shown in FIG. 1; Fig. 3 is a schematic side view of the backup roll shown in fig. 1. In the figure, the reference numerals are 1, a clamp, 2, a supporting roller, 3, a loading pin, 4, a positioning gasket, 5, a strain gauge, 6, a sample to be tested, 7 and a dynamic strain gauge. Detailed Description The utility model will be further described with reference to the drawings and embodiments. Referring to fig. 1, fig. 2 and fig. 3 in combination, fig. 1 is a schematic cross-sectional structure diagram of a device for preparing and monitoring a fracture toughness test specimen pre-crack with multiple dimensions according to a preferred embodiment of the present utility model, fig. 2 is a schematic side view of fig. 1, and fig. 3 is a schematic side view of a backup roll of fig. 1. The preparation and monitoring device suitable for the multi-size fracture toughness sample prefabricated