A tooling fixture for fracture toughness specimen machining

Abstract

The utility model discloses a tool fixture for fracture toughness sample processing, including two parallel and opposite half chuck, two half chucks's structure is completely same, every half chuck includes a clamping part, the clamping part includes at least two clamping part planes and at least two clamping part side, and the clamping part plane and clamping part side integrated alternately connect, and the clamping part plane and clamping part side of interconnection are perpendicular to each other and constitute clamping part step groove, and the height of every clamping part step groove is 10~20mm. The utility model designs the tool fixture with clamping part step groove, and through the height combination of multiple clamping part step grooves, matches the fracture toughness compact tensile sample of different size thickness, under the prerequisite that need not frequently change tool fixture, can realize the quick clamping of different size sample and high accuracy processing, improves the efficiency of test processing.

Description

Technical Field

[0001] This utility model belongs to the technical field of material performance testing devices, and relates to a processing device for fracture toughness test specimens, specifically a tooling fixture for processing fracture toughness test specimens. Background Technology

[0002] With the development of aircraft structural design concepts and the emergence of damage tolerance design principles, the formation and propagation of fatigue cracks in metals have received considerable attention. Effectively understanding and controlling the material's resistance to crack propagation during this stage will significantly improve the material's application prospects and the accuracy of aircraft life estimation. Therefore, the fatigue crack propagation performance of materials has become one of the key performance indicators for design, material selection, and life estimation.

[0003] One of the technical indicators of fatigue crack propagation performance of materials is fracture toughness compact tensile test. However, the fracture toughness compact tensile test specimen process is complex and is a major challenge in specimen processing. The processing of specimens of different sizes requires frequent changes of different tooling fixtures. The previous fixtures have a narrow range of applications and cannot be compatible with specimens of various sizes. Furthermore, it is necessary to change the pads of different sizes at the bottom according to the specimen thickness. Therefore, it is necessary to rely on manual leveling, which is inefficient. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this utility model is to provide a tooling fixture for processing fracture toughness test specimens. This solves the technical problem in existing technologies where, when processing fracture toughness test specimens, the fixture cannot accommodate specimens of various sizes, requiring the replacement of different sized pads at the bottom according to the specimen thickness and manual leveling, resulting in low efficiency.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A tooling fixture for processing fracture toughness test specimens includes two parallel and oppositely arranged half-clamps, the two half-clamps having identical structures; each half-clamp includes a clamping part; the clamping part includes at least two clamping part planes and at least two clamping part sides, the clamping part planes and clamping part sides are integrally and alternately connected, the connected clamping part planes and clamping part sides are perpendicular to each other and form a clamping part stepped groove, the height of each clamping part stepped groove is 10-20mm.

[0007] This utility model also has the following technical features:

[0008] Specifically, the clamping part includes a clamping part base side surface, a clamping part first plane, a clamping part first side surface, a clamping part second plane, and a clamping part second side surface, which are integrally connected from bottom to top. The clamping part first plane and the clamping part first side surface are perpendicular to each other and form a clamping part first stepped groove. The clamping part second plane and the clamping part second side surface are perpendicular to each other and form a clamping part second stepped groove. The height of the clamping part second side surface is less than the height of the clamping part first side surface.

[0009] Specifically, the front and rear sides of the clamping part are integrally connected with a forward cutting part and a rear cutting part with identical structures; the forward cutting part includes at least two cutting part planes and at least two cutting part curved side surfaces, the cutting part planes and cutting part curved side surfaces are integrally and alternately connected, the connected cutting part planes and cutting part curved side surfaces are perpendicular to each other and form a cutting part stepped groove.

[0010] Specifically, the forward cutting section includes, from bottom to top, an integrally connected base side surface, a first plane surface, a first curved side surface, a second plane surface, and a second curved side surface. The first plane surface and the first curved side surface are perpendicular to each other and form a first stepped groove in the cutting section. The second plane surface and the second curved side surface are perpendicular to each other and form a second stepped groove in the cutting section.

[0011] Specifically, the curved side surface of the feed section includes a curved side rectangular surface, and at least two curved side cylindrical surfaces are integrally connected to the front and rear sides of the curved side rectangular surface; the curved side cylindrical surface includes at least one convex surface and at least one concave surface.

[0012] Specifically, the first curved side surface of the feed section includes a rectangular surface of the first curved side surface. The front and rear sides of the rectangular surface of the first curved side surface are sequentially and integrally connected to a first cylindrical surface of the first curved side surface, a second cylindrical surface of the first curved side surface, and a third cylindrical surface of the first curved side surface. The first cylindrical surface of the first curved side surface is a concave surface, and the second and third cylindrical surfaces of the first curved side surface are convex surfaces.

[0013] Specifically, the second curved side surface of the feed section includes a rectangular surface of the second curved side surface. The front side of the rectangular surface of the second curved side surface is integrally connected to a first cylindrical surface of the second curved side surface, a second cylindrical surface of the second curved side surface, and a third cylindrical surface of the second curved side surface. The first cylindrical surface of the second curved side surface is a concave surface, and the second and third cylindrical surfaces of the second curved side surface are convex surfaces. The rear side of the rectangular surface of the second curved side surface is integrally connected to a fourth cylindrical surface of the second curved side surface and a fifth cylindrical surface of the second curved side surface. The fourth cylindrical surface of the second curved side surface is a concave surface, and the fifth cylindrical surface of the second curved side surface is a convex surface.

[0014] Specifically, the front side of the forward cutting section is integrally connected to a front transition section, and the rear side of the rear cutting section is integrally connected to a rear transition section. The structures of the front transition section and the rear transition section are exactly the same. The front transition section includes at least two transition section planes and at least two transition section sides. The transition section planes and transition section sides are integrally and alternately connected. The connected transition section planes and transition section sides are perpendicular to each other and form a transition section stepped groove.

[0015] Specifically, the front transition portion includes, from bottom to top, an integrally connected transition portion base side surface, a transition portion first plane, a transition portion first side surface, a transition portion second plane, and a transition portion second side surface. The transition portion first plane and the transition portion second plane are perpendicular to each other and form a front transition portion first stepped groove, and the transition portion second plane and the transition portion second side surface are perpendicular to each other and form a front transition portion second stepped groove.

[0016] Specifically, each of the half-clamps has at least two threaded holes at its bottom.

[0017] Specifically, and optionally, the height of the stepped groove in each clamping part is different.

[0018] Specifically, the stepped groove of the clamping part is used to clamp fracture toughness specimens with a thickness of 20mm to 50mm. More specifically, it is used to clamp fracture toughness specimens with thicknesses of 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, and 50mm.

[0019] Compared with the prior art, this utility model has the following technical effects:

[0020] This invention designs a tooling fixture with stepped grooves for clamping parts. By combining the heights of multiple stepped grooves for clamping parts, it can match tensile test specimens of different sizes and thicknesses with different fracture toughness. After each specimen change, there is no need to replace the pads of different sizes at the bottom and manually correct the level again. This enables rapid clamping and high-precision processing of specimens of different sizes, thus improving the efficiency of test processing. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the planar structure of the tooling fixture used for processing fracture toughness test specimens.

[0022] Figure 2 This is a schematic diagram of the overall structure of the tooling fixture used for processing fracture toughness test specimens.

[0023] Figure 3 This is a schematic diagram of the stepped groove in the feed section.

[0024] Figure 4 This is a schematic diagram showing the dimensional parameters of the stepped groove for the clamping part.

[0025] The meanings of the labels in the diagram are as follows: 1-clamping part, 2-front transition part, 3-forward cutting part, 4-rear cutting part, 5-rear transition part, 6-threaded hole.

[0026] 101 - Base side of clamping part, 102 - First plane of clamping part, 103 - First side of clamping part, 104 - Second plane of clamping part, 105 - Second side of clamping part.

[0027] 201 - Side surface of the base of the transition section, 202 - First plane of the transition section, 203 - First side surface of the transition section, 104 - Second plane of the transition section, 105 - Second side surface of the transition section.

[0028] 301 - Side surface of the feed section base, 302 - First plane of the feed section, 303 - First curved side surface of the feed section, 304 - Second plane of the feed section, 305 - Second curved side surface of the feed section.

[0029] 30301 - Rectangular surface of the first curved side, 30302 - First cylindrical surface of the first curved side, 30303 - Second cylindrical surface of the first curved side, 30304 - Third cylindrical surface of the first curved side.

[0030] 30501 - Second curved side rectangular surface, 30502 - Second curved side first cylindrical surface, 30503 - Second curved side second cylindrical surface, 30504 - Second curved side third cylindrical surface, 30505 - Second curved side fourth cylindrical surface, 30506 - Second curved side fifth cylindrical surface.

[0031] The specific content of this utility model will be further explained in detail below with reference to the embodiments. Detailed Implementation

[0032] It should be noted that, unless otherwise specified, all components in this utility model are components known in the art.

[0033] The following are specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments. All equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0034] Example:

[0035] This embodiment provides a tooling fixture for machining fracture toughness test specimens, such as... Figure 1 As shown, it includes two parallel and oppositely arranged half-clamps, and the two half-clamps have identical structures; as Figure 2 As shown, each half-clamp includes a front transition section 2, a forward cutting section 3, a clamping section 1, a rear cutting section 4, and a rear transition section 5, which are integrally arranged from front to back.

[0036] As a specific embodiment, the clamping part 1 includes a clamping part base side surface 101, a clamping part first plane 102, a clamping part first side surface 103, a clamping part second plane 104, and a clamping part second side surface 105, which are integrally connected from bottom to top. The clamping part first plane 102 and the clamping part first side surface 103 are perpendicular to each other and form a clamping part first stepped groove. The clamping part second plane 104 and the clamping part second side surface 105 are perpendicular to each other and form a clamping part second stepped groove. The height of the clamping part second side surface 105 is less than the height of the clamping part first side surface 103.

[0037] In this embodiment, to meet the requirements of fracture toughness test specimens, the second stepped groove of the clamping part is used to process smaller samples with thicknesses of 20mm, 25mm, 30mm, etc., and the height h2 of the second stepped groove of the clamping part is 10mm; the first stepped groove of the clamping part is used to process larger samples with thicknesses of 35mm, 40mm, 45mm, 50mm, etc., and the height h1 of the first stepped groove of the clamping part is 20mm. The length of the clamp is determined according to the length of the guide rail.

[0038] As a specific embodiment, the front transition portion 2 and the rear transition portion 5 have the same structure and size.

[0039] As a specific embodiment, the front transition section 2 includes a transition section base side surface 201, a transition section first plane 202, a transition section first side surface 203, a transition section second plane 104, and a transition section second side surface 105, which are integrally connected from bottom to top. The transition section first plane 202 and the transition section second plane 104 are perpendicular to each other and form a front transition section first stepped groove, and the transition section second plane 104 and the transition section second side surface 105 are perpendicular to each other and form a front transition section second stepped groove.

[0040] As a specific embodiment, the forward cutting section 3 and the rear cutting section 4 have completely identical structures.

[0041] As a specific embodiment, the forward cutting section 3 includes a cutting section base side surface 301, a cutting section first plane 302, a cutting section first curved side surface 303, a cutting section second plane 304, and a cutting section second curved side surface 305, which are integrally connected from bottom to top. The cutting section first plane 302 and the cutting section first curved side surface 303 are perpendicular to each other and form a cutting section first stepped groove. The second plane 203 and the cutting section second curved side surface 305 are perpendicular to each other and form a cutting section second stepped groove.

[0042] As a specific solution in this embodiment, the first curved side surface 303 of the feed section includes a first curved side rectangular surface 30301. The front and rear sides of the first curved side rectangular surface 30301 are sequentially and integrally connected to a first curved side first cylindrical surface 30302, a first curved side second cylindrical surface 30303, and a first curved side third cylindrical surface 30304. The first curved side first cylindrical surface 30302 is a concave surface, and the first curved side second cylindrical surface 30303 and the first curved side third cylindrical surface 30304 are convex surfaces.

[0043] As a specific embodiment, the second curved side surface 305 of the tool feed section includes a rectangular surface 30501. The front side of the rectangular surface 30501 is sequentially and integrally connected to a first cylindrical surface 30502, a second cylindrical surface 30503, and a third cylindrical surface 30504. The first cylindrical surface 30502 is a concave surface, while the second cylindrical surface 30503 and the third cylindrical surface 30504 are convex surfaces. The rear side of the rectangular surface 30501 is sequentially and integrally connected to a fourth cylindrical surface 30505 and a fifth cylindrical surface 30506. The fourth cylindrical surface 30505 is a concave surface, and the fifth cylindrical surface 30506 is a convex surface.

[0044] In this embodiment, as described above, the “3” shaped design on both sides of the fixture is a clearance setting for the tool entry point during processing, which facilitates tool entry from any location and makes sample processing easier.

[0045] As a specific embodiment, each half-clamp has two threaded holes 6 at its bottom. In this embodiment, the threaded holes 6 cooperate with the M12 bolts to improve the connection between the clamp and the guide rail and reduce the wobbling of the clamp during processing.

[0046] As a specific solution in this embodiment, since the fixture needs to withstand large processing forces and clamping forces, it needs to be resistant to deformation and damage. In order to ensure the accuracy of long-term use, it needs to be made of materials with high hardness and good wear resistance. Tool steel, cast iron and other materials can generally be selected as the materials for the fixture.

[0047] The working process of this utility model is as follows, taking the processing of two samples with thicknesses of 20mm and 40mm respectively: After installing this fixture, the "zero" point coordinates are confirmed and the straightness and parallelism are calibrated. Subsequent processing does not require such procedures. The first 20mm thick fracture toughness sample to be processed is placed on the first plane 102 of the clamping part and clamped by the first side 103 of the clamping part for processing. If the second sample needs to be processed to 40mm, the material can be directly placed on the second plane 104 of the clamping part and clamped by the second side 105 of the clamping part for subsequent sample processing. There is no need to change the fixture or perform "zero" point calibration, parallelism confirmation, straightness confirmation, etc. again.

[0048] This utility model discloses a tooling fixture for processing fracture toughness test specimens. By holding the specimens to be processed at clamping plates of different specifications, it enables the processing of KIC specimens in the full range of sizes (20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm) without changing the fixtures. Since each time the fixture is changed, it is necessary to perform tool setting, determine the "zero" point coordinates of the new fixture, and confirm the straightness and parallelism after the fixture change, the time required for changing the fixture is about 1.5 hours, which greatly improves the processing efficiency.

Claims

1. A tooling fixture for processing fracture toughness test specimens, comprising two parallel and oppositely arranged half-clamps with identical structures, each half-clamp including a clamping part (1); characterized in that: Each clamping part (1) includes at least two clamping part planes and at least two clamping part sides, which are integrally and alternately connected. The connected clamping part planes and clamping part sides are perpendicular to each other and form a clamping part stepped groove. The height of each clamping part stepped groove is 10 to 20 mm.

2. The tooling fixture for processing fracture toughness test specimens as described in claim 1, characterized in that, The front and rear sides of the clamping part (1) are integrally connected with a forward cutting part (3) and a rear cutting part (4) with identical structures.

3. The tooling fixture for processing fracture toughness test specimens as described in claim 2, characterized in that, The forward cutting section (3) includes at least two cutting section planes and at least two cutting section curved side surfaces. The cutting section planes and cutting section curved side surfaces are integrally and alternately connected. The connected cutting section planes and cutting section curved side surfaces are perpendicular to each other and form a cutting section stepped groove.

4. The tooling fixture for processing fracture toughness test specimens as described in claim 2, characterized in that, The curved side surface of the feed section includes a rectangular curved side surface, and at least two cylindrical curved side surfaces are integrally connected to the front and rear sides of the rectangular curved side surface.

5. The tooling fixture for processing fracture toughness test specimens as described in claim 4, characterized in that, The curved side cylindrical surface includes at least one convex surface and at least one concave surface.

6. The tooling fixture for processing fracture toughness test specimens as described in claim 2, characterized in that, The front side of the forward cutting section (3) is integrally connected to the front transition section (2), and the rear side of the rear cutting section (4) is integrally connected to the rear transition section (5). The structures of the front transition section (2) and the rear transition section (5) are completely identical.

7. The tooling fixture for processing fracture toughness test specimens as described in claim 6, characterized in that, The front transition section (2) includes at least two transition section planes and at least two transition section sides. The transition section planes and transition section sides are integrally and alternately connected. The connected transition section planes and transition section sides are perpendicular to each other and form a transition section stepped groove.

8. The tooling fixture for processing fracture toughness test specimens as described in claim 1, characterized in that, Each of the half-clamps has at least two threaded holes (6) at its bottom.

9. The tooling fixture for processing fracture toughness test specimens as described in claim 1, characterized in that, The height of each clamping step groove is different.

10. The tooling fixture for processing fracture toughness test specimens as described in claim 1, characterized in that, The stepped groove of the clamping part is used to clamp fracture toughness specimens with a thickness of 20mm to 50mm.

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