CN113740152B - CT test piece, CT test method and CT test device - Google Patents

CT test piece, CT test method and CT test device Download PDF

Info

Publication number
CN113740152B
CN113740152B CN202010461770.1A CN202010461770A CN113740152B CN 113740152 B CN113740152 B CN 113740152B CN 202010461770 A CN202010461770 A CN 202010461770A CN 113740152 B CN113740152 B CN 113740152B
Authority
CN
China
Prior art keywords
test piece
test
composite material
piece
wedge
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202010461770.1A
Other languages
Chinese (zh)
Other versions
CN113740152A (en
Inventor
张婷
李颖
李向前
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
AECC Commercial Aircraft Engine Co Ltd
Original Assignee
AECC Commercial Aircraft Engine Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by AECC Commercial Aircraft Engine Co Ltd filed Critical AECC Commercial Aircraft Engine Co Ltd
Priority to CN202010461770.1A priority Critical patent/CN113740152B/en
Publication of CN113740152A publication Critical patent/CN113740152A/en
Application granted granted Critical
Publication of CN113740152B publication Critical patent/CN113740152B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02—Details
    • G01N3/04—Chucks
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0014—Type of force applied
    • G01N2203/0016—Tensile or compressive
    • G01N2203/0017—Tensile
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0014—Type of force applied
    • G01N2203/0016—Tensile or compressive
    • G01N2203/0019—Compressive
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0058—Kind of property studied
    • G01N2203/006—Crack, flaws, fracture or rupture
    • G01N2203/0062—Crack or flaws
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0058—Kind of property studied
    • G01N2203/006—Crack, flaws, fracture or rupture
    • G01N2203/0067—Fracture or rupture
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02—Details not specific for a particular testing method
    • G01N2203/04—Chucks, fixtures, jaws, holders or anvils

Landscapes

  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)

Abstract

The invention provides a CT test piece for testing the performance of a composite material, which is made of the composite material, and is formed by removing two corners of a rectangular flat plate and arranging V-shaped notches with tips facing the common edge on opposite edges of the common edge of the two corners. The invention also provides a CT test method and a CT test device adopting the CT test piece. By adopting the CT test piece, the problem that the test piece is easy to generate out-of-plane buckling at the rear part too early in the process of CT test on the high-toughness composite material, so that the effective fracture toughness of the material cannot be obtained can be avoided.

Description

CT test piece, CT test method and CT test device
Technical Field
The invention provides a CT test piece for testing the performance of a composite material, and also relates to a CT test method for testing the performance of the composite material and a CT test device for testing the performance of the composite material.
Background
Fiber reinforced composite materials are increasingly being used in the aerospace field due to their high strength, corrosion resistance, and other advantages. However, during actual production and service, the composite material often encounters impact load, and is susceptible to damage due to its sensitivity to the impact load, thereby resulting in a reduction in the load-bearing capacity and load-bearing strength of the composite laminate member; meanwhile, most composite laminated plates need to be perforated or have various notches and cracks, and serious stress concentration phenomenon exists near the notches, and the stress concentration can lead to crack expansion and damage expansion, so that the strength of the laminated plates can be reduced. Therefore, the mechanical property and fracture toughness of the composite material under the action of research load have very practical significance, and are also increasingly receiving attention from academia and engineering circles.
Currently, fiber reinforced composites do not have uniform, reasonable test criteria for fracture toughness, and common test methods include three-point bending tests, compact Tension (CT) tests, drop hammer tests, and wide plate tests. The tensile test is divided into compact stretching, C-shaped stretching, round compact stretching and unilateral notch stretching according to the size and the configuration of the sample. However, since the composite material has a series of phenomena such as matrix cracking, fiber-matrix debonding, fiber pulling-out and fracture in the process of crack propagation, these test methods cannot accurately evaluate the actual crack propagation and fracture behavior of the composite material, and many researchers still perform a great deal of test improvement work.
From the perspective of saving test materials, the CT test is a test method for better obtaining the fracture toughness of the fiber reinforced composite material, and generally, the standard geometric shape of a CT test piece is shown as shown in figure 1, namely, the CT test piece comprises a rectangular sample body, a certain length of cracks are machined on the body, and circular holes are symmetrically formed on the body and symmetrically arranged on the left side and the right side of a deep groove. However, since the load required for a composite to propagate a crack is proportional to the tensile strength of the material, materials with relatively low compressive strength to tensile strength tend to prematurely buckle out of plane at the rear of the test piece, i.e., on the opposite side of the round hole, thereby failing to achieve the desired material properties; meanwhile, a tensile hole is usually formed in the clamping end of a conventional CT test piece, so that local compression damage can be inevitably generated around the hole or at other near holes, and the properties such as fracture toughness of the material cannot be accurately obtained.
Disclosure of Invention
An object of the present invention is to provide a CT test piece for testing performance of a composite material, which can avoid the problem that the CT test piece is easy to generate out-of-plane buckling at the rear part too early in the process of performing CT test on a high-toughness composite material, so that effective fracture toughness of the material cannot be obtained.
Another object of the present invention is to provide a CT test piece, a CT test method, and a CT test apparatus for testing the performance of a composite material, which can avoid the problem that the vicinity of a tensile hole is easily damaged in advance during the CT test of the composite material, and effective fracture toughness of the material cannot be obtained.
It is still another object of the present invention to provide a CT test piece, a CT test method, and a CT test apparatus for testing the performance of a composite material, which can automatically propagate only a main crack during the CT test of the composite material, and can effectively inhibit the occurrence of phenomena such as cracking of a matrix, debonding of fibers from the matrix, fiber extraction, and fracture.
The invention provides a CT test piece for testing the performance of a composite material, which is made of the composite material, and is formed by removing two corners through a rectangular flat plate and arranging V-shaped notches with tips facing to a common edge of the two corners at opposite edges of the common edge.
The invention provides a CT test method for testing the performance of a composite material, wherein the CT test piece is provided; providing a wedge block; CT experiments were performed by wedging the wedge into the V-notch and applying pressure towards the common edge.
In one embodiment, simulating a CT test process of a CT standard test piece by a finite element method to obtain a failure mode distribution map of the CT standard test piece; changing the geometric configuration of the test piece through finite element method simulation according to the failure mode distribution diagram, so as to obtain the geometric configuration of the CT test piece capable of inhibiting the ineffective failure mode of the CT test.
In one embodiment, the head of the wedge has rounded corners.
In one embodiment, the wedge moves at a constant rate toward the common edge.
In one embodiment, a quasi-static tensile tester is used to control the speed of the wedge block and the amount of load applied to the CT test piece.
In one embodiment, the CT test piece is made of a carbon fiber reinforced epoxy resin fabric material, and the V-shaped notch has the following dimensions: 4.7 mm. Times.4 mm. Times.60 mm.
In one embodiment, fracture toughness is calculated according to the following formula:
wherein ,e1 and E2 respectively represent the flexural modulus of the CT test piece at two sides of the V-shaped notch, h1 and h2 respectively represent the width of the CT test piece at two sides of the V-shaped notch, a is the depth of the V-shaped notch, and delta is the crack opening displacement of the CT test piece.
In one embodiment, the CT test piece is symmetrically shaped.
The invention also provides a CT test device for testing the performance of the composite material, wherein the upper die is provided with a wedge-shaped block, and the lower die is used for positioning the CT test piece; the upper die is movably arranged relative to the lower die, so that the wedge-shaped block can be wedged into the V-shaped notch.
The invention adopts the irregular trapezoid CT test piece to replace the rectangular CT standard test piece, and can avoid the premature out-of-plane buckling of the rear part of the test piece, thereby truly and effectively obtaining the fracture toughness of the material, and particularly solving the problem of measuring the mechanical properties of the composite material with high toughness and large thickness under the load action in the industry.
According to the CT test method and the CT test device adopted by the invention, the wedge-shaped blocks are adopted and compressive load is applied instead of tensile load, so that bending and out-of-plane shearing damage near the tensile hole of the test piece can be avoided.
The CT test method and the CT test device can effectively control the expansion speed and the expansion path of the crack by controlling the speed of the wedge block and the load loaded on the CT test piece, thereby truly and effectively inspecting the crack expansion capability of the material.
The invention adopts the special CT test device as the fixture for fixing the CT test piece, and can effectively avoid the problems of eccentricity and the like in the CT test process, thereby ensuring that the obtained test data is true and effective, reducing the test failure probability and greatly saving the test cost.
Drawings
The above and other features, properties and advantages of the present invention will become more apparent from the following description in conjunction with the accompanying drawings and embodiments, in which:
fig. 1 is a front view of a CT standard test piece.
Fig. 2 is a side view of a CT standard test piece.
FIG. 3 is a schematic view of the location of potential failure of a CT standard test piece.
Fig. 4 is a schematic structural view of a CT test apparatus.
Fig. 5 is a front view of a CT test piece.
Detailed Description
The present invention will be further described with reference to the following detailed description and the accompanying drawings, in which more details are set forth in order to provide a thorough understanding of the present invention, but it will be apparent that the present invention can be embodied in many other forms than described herein, and that those skilled in the art may make similar generalizations and deductions depending on the actual application without departing from the spirit of the present invention, and therefore should not be limited in scope by the context of this detailed description.
For example, a first feature described later in this specification may be formed above or on a second feature, and may include embodiments in which the first and second features are formed in direct contact, as well as embodiments in which additional features are formed between the first and second features, such that no direct contact between the first and second features is possible. Further, where a first element is described as being coupled or combined with a second element, the description includes embodiments in which the first and second elements are directly coupled or combined with each other, and also includes embodiments in which one or more other intervening elements are added to indirectly couple or combine the first and second elements with each other.
As a conventional CT test piece for testing the performance of a composite material, a CT standard test piece 20 designed with reference to ASTM E399 standard is, as shown in fig. 1 and 2, generally rectangular flat plate-like, having a rectangular opening 21, and the rectangular opening 21 has a pre-formed crack 22 (omitted from fig. 2) on the side facing the opposite side 24, for example, cut by a wire saw. In the CT standard test piece 20, the tensile holes 23 are provided on both sides of the rectangular opening 21.
The CT standard test piece 20 has a length l20, a width w20, and a thickness t20. The diameter of the stretching holes 23 is d3, and the interval between the two stretching holes 23 is g3; the length of the rectangular opening 21 is l21, and the width of the rectangular opening 21 is w21; the length of the pre-crack 22 is l22; the distance between the center of the stretch hole 23 and the straight edge 25 on which the opening side is located is d35, and the distance between the center of the stretch hole 23 and the bottom of the pre-crack 22 is d32.
The present invention provides a CT test piece 10 for testing the performance of an optimized composite material, as shown in FIG. 5. The CT test piece 10 is formed by removing two corners 12, 13 from a rectangular flat plate 11 and disposing tips 161 toward V-shaped notches 16 of the common side 14 at opposite sides 15 of the common side 14 of the aforementioned two corners 12, 13. Preferably, the CT test piece 10 is symmetrically shaped. This shape of the CT test piece 10 resembles the shape of a trapezoid plus a rectangle, or what is known as an irregular trapezoid.
The CT test piece 10 described above no longer employs the rectangular opening and linear pre-crack or rectangular opening plus V-tip designs of conventional CT test pieces, but rather takes the form of a V-notch 16. In the illustrated embodiment, the V-notch 16 may be formed entirely as a pre-crack. In another embodiment, a linear crack similar to the pre-crack 22 of FIG. 1 may be added to the side of the V-notch 16 facing the common edge 14, the V-notch 16 and the linear crack together acting as a pre-crack, which may enhance the fracture effect.
The geometry of the CT test piece 10 is obtained by the following method: simulating a CT test process of the CT standard test piece 20 by a finite element method to obtain a failure mode distribution diagram of the CT standard test piece 20, as shown in FIG. 3; the geometric configuration of the test piece, that is, the geometric configuration of the CT test piece 10, in which the ineffective failure mode of the CT test can be suppressed, is obtained by changing the geometric configuration of the test piece by the finite element method simulation according to the failure mode distribution diagram shown in FIG. 3 described above.
In one embodiment, the method of obtaining the geometry of the CT test 10 may be performed as follows:
1) Design of CT Standard test piece 20
CT standard test piece 20 was initially designed with reference to ASTM E399 standard.
When the CT standard test piece 20 is designed, the layering, thickness and size of the CT standard test piece 20 can be defined, and the CT standard test piece can be made of carbon fiber reinforced epoxy resin fabric materials. For example, the CT standard test piece 20 has dimensions of 120mm by 8mm, that is, a length l20, a width w20, and a thickness t20 of 180mm, 120mm, and 8mm, respectively. It is to be understood that the drawings are by way of example only and are not drawn to scale and should not be construed to limit the true scope of the invention.
2) Finite element simulation CT test
The CT test procedure of the CT standard test piece 20 is simulated by a finite element method, for example, using Abaqus software.
A failure mode profile of the CT standard test piece 20 during the CT test is obtained as shown in fig. 3. In fig. 3, A1, A2, A3, A4, A5, A6 respectively represent a trailing edge compressive stress region, an upper edge compressive stress region, a lower edge compressive stress region, a pre-crack rear end compressive stress region, a loading head contact end compressive stress region, a loading head compression and longitudinal and transverse shearing failure prone region, a trailing edge out-of-plane twist failure prone region (or a trailing edge twist failure prone region), and an "x" indicated by B0 represents a loading head and test piece contact point.
According to the failure mode profile shown in fig. 3, the geometry of the test piece is changed by the finite element method simulation, in other words, the geometry of the CT test piece is optimized. The geometry that suppresses the ineffective failure mode of the CT test is finally obtained, i.e. the geometry of the CT test piece 10 is obtained, resulting in the machining angle for the two corners 12, 13 and the specific dimensions of the V-notch 16 in the CT test piece 10. The compressive stress of the trailing edge compressive stress region A1 is effectively reduced by employing the bottom end both side cut corners of the rectangular flat plate 11. The width w0 of the test piece can be reduced to 15mm, and by greatly reducing the width w0 (shown in fig. 5), the compressive stress of the compressive stress area A3 at the rear end of the pre-crack, the compressive stress of the compressive stress areas A2 at the upper edge and the lower edge and the failure risk of the out-of-plane distortion failure area A6 at the tail edge can be effectively reduced, and the material consumption of the CT test piece 10 can be effectively reduced.
In the CT test process, the CT test piece 10 adopting the geometric configuration is not easy to cause out-of-plane buckling at the rear part too early, and effective material fracture toughness is easy to obtain, especially when CT test is carried out on a composite material with high toughness and large thickness.
After the geometry of the CT test piece 10 is obtained, raw materials are prepared according to the optimized geometry (i.e., the geometry of the CT test piece 10), the CT test piece is laid down and cured according to the corresponding material and process specifications, and a V-shaped notch 16 of a certain size is machined by a wire cutting method. Thus, the CT test piece 10 was manufactured and processed. The laying can be performed according to a CT test piece laying design, and the curing can be performed according to a prepreg standard curing process.
Preferably, when the CT test piece 10 is made of carbon fiber reinforced epoxy fabric material, the V-shaped notch 16 may have a size of: 4.7 mm. Times.4 mm. Times.60 mm. That is, in connection with fig. 4 and 5, the thickness t1, the opening width w11, and the depth a of the v-shaped notch 16 are 4.7mm, 4mm, and 60mm, respectively. It will be appreciated that the thickness t1 of the V-notch 16 is also the thickness of the CT test piece 10. It is noted that the two corners 12, 13 are machined without being cut to fiber.
In the CT test method for testing the performance of the composite material, the optimized CT test piece 10 is provided; providing a wedge block 2 as shown in fig. 4; CT tests were performed by wedging wedge block 2 into V-notch 16 of CT test piece 10 and applying pressure toward common edge 14.
In the CT test method, the crack propagation is not carried out in a traditional tensile loading mode, but is applied in a compression loading mode through a wedge block. The CT test piece 10 may not need to be provided with a stretch hole, and may avoid shearing damage at the stretch hole, so that the problem that the vicinity of the stretch hole is easily damaged in advance in the conventional CT test process, and effective fracture toughness of the material cannot be obtained is avoided. The wedge-shaped block 2 is used as a wedge-shaped loading head to be inserted into the surface contact loading of the V-shaped notch 16 (the pre-crack groove), so that the point contact compression damage risk of the loading head in the compression stress area A4 of the contact end of the loading head and the compression and longitudinal and transverse shearing coupling damage risk of the compression and longitudinal and transverse shearing easy-failure area A5 of the loading head can be effectively reduced. Fracture toughness can be calculated according to the following equation (1):
wherein ,e1 and E2 represent the flexural moduli on both sides of the V-notch 16 of the CT test piece 10, respectively, h1 and h2 represent the widths of the center line C1 of the V-notch 16 to both sides of the CT test piece 10, a is the depth of the V-notch 16 (as described above), and Δ is the crack opening displacement of the CT test piece 10. In fig. 5, the center line C1 is a vertical line passing through the tip 161 (or, the cusp) of the V-notch 16. The crack opening displacement of the CT test piece 10, that is, the amount of change in the opening width w11 of the V-notch 16 of the CT test piece 10.
In the embodiment shown in fig. 4, the head 201 of the wedge 2 has rounded corners, in other words, the top of the wedge 2 may be curved.
In the CT test method for testing the performance of the composite material, the wedge-shaped block 2 can move towards the common edge 14 at a constant speed. A quasi-static tensile tester can be used to control the speed of wedge block 2 and the amount of load applied to CT test piece 10. In this way, the crack propagation speed and propagation path can be effectively controlled, so that the crack propagation capability of the material can be effectively examined. The control of the load applied to the CT test piece 10 can be realized by controlling the load displacement, for example.
Fig. 4 also shows a CT test apparatus 30 for testing composite properties, comprising an upper die 3 and a lower die 4. The upper die 3 provides a wedge 2 and the lower die 4 positions the CT test piece 10, for example, by supporting the CT test piece 10 through a sample base 40 as shown in FIG. 4. The upper die 3 is movably arranged relative to the lower die 4, for example guided by guide posts 5, so that the wedge blocks 2 can be wedged into V-notches 16 of the CT-test piece 10. It will be appreciated that for convenience of description, spatial relationship terms such as "lower", "upper", and the like may be used herein to describe one element or feature's relationship to another element or feature shown in the figures. It will be appreciated that these spatially relative terms are intended to encompass other orientations of the element or component in use or operation in addition to the orientation depicted in the figures. For example, if the component in the drawings is turned over, elements described as "under" other elements or features would then be oriented "over" the other elements or features, and the spatially relative descriptors used herein should be interpreted accordingly. The CT test apparatus 10 has the advantages of portability, rapidness, strong operability, and the like.
In fig. 4, the upper die 3 is divided into a first upper die block 31 and a second upper die block 32. The first upper module 31 has a receiving groove 33, and the wedge block 2 is disposed on the second upper module 32. When the first upper module 31 and the second upper module 32 are aligned, the wedge block 2 is placed in the accommodating groove 33. The lower die 4 is divided into a first lower die block 41 and a second lower die block 42. The sample holder 40 is provided on the second lower module 42, and the ct test piece 10 is placed on the sample holder 40. The first lower module 41 and the second lower module 42 can clamp and position the CT test piece 10 when being aligned.
The first upper die block 31 and the second upper die block 32 of the upper die 3 are respectively provided with guide holes 34, and are respectively matched with guide posts 5 arranged on the first lower die block 41 and the second lower die block 42 of the lower die 4 to guide the upper die 3 to move up and down relative to the lower die 4.
The CT test device 30 can be placed on a compression platform of a quasi-static tensile testing machine, and the whole CT test device 30 can be limited by a limiting piece. The ram of the quasi-static tensile tester can set a constant rate, compressing the first upper module 31 and the second upper module 32 of the upper die 3, thereby pushing the wedge block 2 to load the CT test piece 10.
When a CT test is carried out, the CT test piece 10 can be clamped on the lower die 4 of the CT test device 30, and the upper die 3 drives the wedge block 2 to stably expand the V-shaped notch 16 along the central axis of the CT test piece 10 in a compression loading mode. During the test, the loading rate of 1mm/min can be ensured, and effective test failure mode and test data, such as a load-displacement curve during a CT test, can be obtained. Finally, the obtained test data are calculated and analyzed, and the quasi-static fracture toughness of the CT test piece 10 is calculated according to the formula (1).
By adopting the CT test piece, the CT test method and the CT test device are further adopted, the damage mode of the CT test piece is single, the fracture toughness of the material can be truly and effectively obtained, the reliability of the test result is remarkably improved, the test failure probability is reduced, and the test cost is reduced.
While the invention has been described in terms of preferred embodiments, it is not intended to be limiting, but rather to the invention, as will occur to those skilled in the art, without departing from the spirit and scope of the invention. For example, the transformation modes in the different embodiments may be combined appropriately. Therefore, any modification, equivalent variation and modification of the above embodiments according to the technical substance of the present invention fall within the protection scope defined by the claims of the present invention.

Claims (7)

1. A CT test method for testing the performance of composite material is characterized in that,
providing a CT test piece, wherein the CT test piece is made of a composite material;
the CT test piece is formed by removing two corners through a rectangular flat plate and arranging V-shaped notches with tips facing the common side at opposite sides of the common side of the two corners;
providing a wedge block;
performing a CT test by wedging the wedge into the V-notch and applying pressure toward the common edge;
wherein fracture toughness is calculated according to the following formula:
wherein ,E 1 and E2 Respectively representing the flexural modulus and h of the two sides of the V-shaped notch of the CT test piece 1 and h2 The widths of the two sides of the V-shaped notch of the CT test piece are respectively represented, a is the depth of the V-shaped notch, and delta is the crack opening displacement of the CT test piece.
2. The CT test method as claimed in claim 1, wherein,
simulating a CT test process of a CT standard test piece by a finite element method to obtain a failure mode distribution diagram of the CT standard test piece;
changing the geometric configuration of the test piece through finite element method simulation according to the failure mode distribution diagram, so as to obtain the geometric configuration of the CT test piece capable of inhibiting the ineffective failure mode of the CT test.
3. The CT test method as claimed in claim 1, wherein,
the head of the wedge block is provided with a round angle.
4. The CT test method as claimed in claim 1, wherein,
the wedge moves at a constant rate toward the common edge.
5. The CT test method as claimed in claim 1, wherein,
a quasi-static tensile tester is used to control the speed of the wedge block and the magnitude of the load applied to the CT test piece.
6. The CT test method as claimed in claim 1, wherein,
the CT test piece is made of carbon fiber reinforced epoxy resin fabric material, and the size of the V-shaped notch is as follows: 4.7 mm. Times.4 mm. Times.60 mm.
7. The CT test method as claimed in claim 1, wherein,
the CT test piece is in a symmetrical shape.
CN202010461770.1A 2020-05-27 2020-05-27 CT test piece, CT test method and CT test device Active CN113740152B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010461770.1A CN113740152B (en) 2020-05-27 2020-05-27 CT test piece, CT test method and CT test device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010461770.1A CN113740152B (en) 2020-05-27 2020-05-27 CT test piece, CT test method and CT test device

Publications (2)

Publication Number Publication Date
CN113740152A CN113740152A (en) 2021-12-03
CN113740152B true CN113740152B (en) 2023-10-27

Family

ID=78723762

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010461770.1A Active CN113740152B (en) 2020-05-27 2020-05-27 CT test piece, CT test method and CT test device

Country Status (1)

Country Link
CN (1) CN113740152B (en)

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58189541A (en) * 1982-04-28 1983-11-05 Ishikawajima Harima Heavy Ind Co Ltd Breakdown test-piece and breakdown testing method
US4567774A (en) * 1983-04-28 1986-02-04 Battelle Development Corporation Determining mechanical behavior of solid materials using miniature specimens
US5386442A (en) * 1993-06-25 1995-01-31 General Electric Company Method and apparatus for controlling the load on double cantilever beam sensors
US5641912A (en) * 1993-02-01 1997-06-24 Manahan, Sr.; Michael Peter Method for remote application of variable load and/or displacement to specimens, components, or systems
CN103207111A (en) * 2013-03-14 2013-07-17 中国石油天然气集团公司 Round-rod tensile sample with annular crack and method for manufacturing round-rod tensile sample
CN103234823A (en) * 2013-04-03 2013-08-07 杭州电子科技大学 Artificial heart valve pyrolytic carbon and testing method for fracture toughness of pyrolytic carbon composite material
CN103900901A (en) * 2014-03-10 2014-07-02 水利部交通运输部国家能源局南京水利科学研究院 Concrete testing device using wedged splitting tensile method
CN105547837A (en) * 2016-01-29 2016-05-04 中国石油大学(华东) Brazing connector fracture toughness test apparatus
JP2016080631A (en) * 2014-10-21 2016-05-16 株式会社島津製作所 Material testing machine
CN105758723A (en) * 2016-02-29 2016-07-13 南京航空航天大学 Test method for crack growth rate of linear gradient material
CN109540694A (en) * 2018-11-27 2019-03-29 浙江工业大学 Precrack for testing II type crack fracture toughness biases 3 points of curved experimental rigs
CN110717298A (en) * 2019-10-15 2020-01-21 西北工业大学 Test data processing method of integral type static force progressive damage model

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58189541A (en) * 1982-04-28 1983-11-05 Ishikawajima Harima Heavy Ind Co Ltd Breakdown test-piece and breakdown testing method
US4567774A (en) * 1983-04-28 1986-02-04 Battelle Development Corporation Determining mechanical behavior of solid materials using miniature specimens
US5641912A (en) * 1993-02-01 1997-06-24 Manahan, Sr.; Michael Peter Method for remote application of variable load and/or displacement to specimens, components, or systems
US5386442A (en) * 1993-06-25 1995-01-31 General Electric Company Method and apparatus for controlling the load on double cantilever beam sensors
CN103207111A (en) * 2013-03-14 2013-07-17 中国石油天然气集团公司 Round-rod tensile sample with annular crack and method for manufacturing round-rod tensile sample
CN103234823A (en) * 2013-04-03 2013-08-07 杭州电子科技大学 Artificial heart valve pyrolytic carbon and testing method for fracture toughness of pyrolytic carbon composite material
CN103900901A (en) * 2014-03-10 2014-07-02 水利部交通运输部国家能源局南京水利科学研究院 Concrete testing device using wedged splitting tensile method
JP2016080631A (en) * 2014-10-21 2016-05-16 株式会社島津製作所 Material testing machine
CN105547837A (en) * 2016-01-29 2016-05-04 中国石油大学(华东) Brazing connector fracture toughness test apparatus
CN105758723A (en) * 2016-02-29 2016-07-13 南京航空航天大学 Test method for crack growth rate of linear gradient material
CN109540694A (en) * 2018-11-27 2019-03-29 浙江工业大学 Precrack for testing II type crack fracture toughness biases 3 points of curved experimental rigs
CN110717298A (en) * 2019-10-15 2020-01-21 西北工业大学 Test data processing method of integral type static force progressive damage model

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
Numerical investigation of progressive damage and the effect of layup in overheight compact tension tests;Xiangqian Li等;Composites: Part A;第43卷;第2137-2150页 *
Study on the effect of the crack length on the JIC value;Masanori Kikuchi;Nuclear Engineering and Design;第174卷;第41-49页 *
双材料CT试样焊缝界面裂纹蠕变断裂参量Ｃ*的工程估算;胡兆吉等;南昌大学学报·工科版;第29卷(第4期);第326-330页 *
孙茂才.金属力学性能.哈尔滨工业大学出版社,2003,(第1版),第122-126页. *

Also Published As

Publication number Publication date
CN113740152A (en) 2021-12-03

Similar Documents

Publication Publication Date Title
Zhang et al. Influence of plate length and anchor position on FRP-to-concrete joints anchored with FRP anchors
Li et al. Elastic and fracture behavior of three-dimensional ply-to-ply angle interlock woven composites: Through-thickness, size effect, and multiaxial tests
CN204556480U (en) A kind of test unit of testing coating test specimen bond strength
CN104764692A (en) Testing device for testing bonding strength of coating specimen
CN102944470A (en) Bending test jig assembly, bending test jig and compression test jig
CN113740152B (en) CT test piece, CT test method and CT test device
CN113203621A (en) Special clamp for mechanical test of plate-shaped sample
Zhou Effect of impact damage on residual compressive strength of glass-fibre reinforced polyester (GFRP) laminates
Zhu et al. Singular fields near a sharp V-notch for power law creep material
Catangiu et al. Experimental results for bending fatigue behaviour of glass-epoxy composite materials
CN111595674A (en) Device capable of loading various stress fields in sample and loading method
CN107247001A (en) A kind of shearing test device and its test method
CN212159374U (en) CT test assembly
CN103471935A (en) Test piece for fracture toughness of III type cracks
CN109030209B (en) Interlayer tensile strength testing device and method for 3D printed concrete member
CN203479643U (en) Test piece for testing fracture toughness of type-III cracks
CN207816740U (en) A kind of experimental provision for studying FRP- concrete interface adhesive properties
CN114486562B (en) Device and method for testing shear strength of composite material
Walker et al. Plastic fracture in poly (vinyl chloride)
CN107976362B (en) Three-point bending fixture
CN203551346U (en) Test piece for energy release rate of twist mode of bonding interface
CN201100860Y (en) Pull testing position device for crisp material testing part thick agglomeration axis
CN209727618U (en) A kind of XCT observation four-point bending experiments supporting mold of subgrade construction
CN111678776A (en) Indirect stretching device for testing tensile strength of rock
CN110646301A (en) Shear test device and method for testing CFRP/steel interface bonding performance

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant