A composite r zone impact point location and damage depth measurement device

Abstract

The present application belongs to the field of impact damage introduction and test of aircraft composite material structure, and particularly relates to a kind of R area impact damage introduction test and damage depth measuring device.The impact point positioning and damage depth measuring device is provided with a recess on the base, at least one threaded hole is provided on the side wall of the recess, and an adjusting bolt is provided in the threaded hole;A support is provided on the base;A support arm is provided on the support, the support arm can move up and down on the support, and a micrometer is provided on the support arm;The support plate is arranged in the recess, the free end of the screw rod of the adjusting bolt abuts against the support plate to fix the support plate;Test piece fixing piece is used to fix the two ends of test piece, test piece fixing piece is arranged on the support plate, and micrometer is opposite to the R area of test piece.The position of impact point and the measurement of impact damage pit are determined by micrometer, the structure is very simple, and the operation is very convenient.

Description

Technical Field

[0001] This invention belongs to the field of impact damage introduction and testing of aircraft composite material structures, and specifically relates to a device for R-zone impact damage introduction test and damage depth measurement. Background Technology

[0002] The R-zone is a typical structural feature of beams and ribs in composite structures. When subjected to out-of-plane compression and bending, R-zone structures generate significant interlaminar stresses. However, the interlaminar strength of composite laminates is very low, making the R-zone prone to delamination failure. Due to the brittleness of the polymer resin, structures subjected to heavy object drops or impacts in real-world environments may suffer delamination or fiber breakage. Therefore, damage impedance is typically determined in the performance evaluation of composite structures. For composite R-zone structures, impact damage severely affects the remaining load-bearing capacity of the R-zone.

[0003] Currently, major domestic and international testing standards for impact damage introduction testing of composite laminates only apply to the impact damage introduction testing of straight composite laminates, and there are no impact testing standards that include curved surfaces, including the R-zone. Furthermore, since both the inner and outer surfaces of the R-zone are curved, the depth of the damage indentation after impact cannot be measured using methods for flat specimens. Therefore, there is an urgent need to design a method for introducing impact damage in the R-zone and a method for measuring the damage depth to address the increasing testing needs of R-zone structural specimens in engineering design applications. Summary of the Invention

[0004] The purpose of this invention is to provide a device for locating impact points and measuring damage depth in the R-zone of composite materials, so as to solve the technical requirements of the R-zone impact test process and the problem of measuring damage depth.

[0005] The objective of this invention is achieved through the following technical solution.

[0006] A composite material R-zone impact point location and damage depth measurement device includes a base, a bracket, a support arm, a support plate, and a test piece fixing component. The base has a groove, and at least one threaded hole is provided on the side wall of the groove. An adjusting bolt is installed in the threaded hole. A bracket is mounted on the base. An arm is mounted on the bracket and can move up and down along the bracket. A dial indicator is mounted on the arm. The support plate is disposed in the groove, and the free end of the adjusting bolt abuts against the support plate to fix the support plate. The test specimen holder is used to fix both ends of the test specimen. The test specimen holder is disposed on the support plate. The dial indicator is directly opposite the R region of the test specimen. It is configured such that: in a first state, the dial indicator is directly opposite a first area of ​​the R region of the test specimen; in a second state, the dial indicator is directly opposite a second area of ​​the R region of the test specimen; the dial indicator and the test specimen can be displaced along the X-axis and Y-axis directions, the X-axis direction being perpendicular to the longitudinal axis of the R region, and the Y-axis direction being parallel to the longitudinal axis of the R region.

[0007] In the aforementioned composite material R-zone impact point positioning and damage depth measurement device, a first track is provided on the bracket, and the support arm can move along the first track to realize the movement of the dial indicator along the X-axis direction;

[0008] In the aforementioned composite material R-zone impact point positioning and damage depth measurement device, a second track is provided on the base, and the lower end of the bracket can move on the second track to realize the movement of the dial indicator along the Y-axis direction.

[0009] The aforementioned composite material R-zone impact point positioning and damage depth measurement device further includes a first motor and a second motor. The first motor is used to drive the support arm to move along the X-axis direction; the first motor is used to drive the bracket to move along the Y-axis direction.

[0010] In the aforementioned composite material R-zone impact point positioning and damage depth measurement device, the support plate can move along the X-axis when the adjusting bolt is in a relaxed state.

[0011] In the aforementioned composite material R-zone impact point positioning and damage depth measurement device, a sliding groove is provided on the support plate, the sliding groove is arranged in the Y-axis direction, a through hole is provided on the test piece fixing member, and a fixing bolt is provided in the through hole. The fixing bolt passes through the through hole and the sliding groove to adjust and fix the position of the test piece fixing member.

[0012] In the aforementioned composite material R-zone impact point positioning and damage depth measurement device, the test piece fixing component includes a first fixing component and a second fixing component. The first fixing component is used to fix a first side of the test piece, and the second fixing component is used to fix a second side of the test piece. Specifically: the first fixing component includes two plates arranged opposite each other and a connecting portion connecting the two plates. The first side is disposed between the two plates, and one of the plates has at least one threaded hole with a bolt in the threaded hole. When tightened, the bolt abuts against the first side to fix the first side. The second fixing component includes two plates arranged opposite each other and a connecting portion connecting the two plates. The second side is disposed between the two plates, and one of the plates has at least one threaded hole with a bolt in the threaded hole. When tightened, the bolt abuts against the second side to fix the second side.

[0013] In the aforementioned composite material R-zone impact point positioning and damage depth measurement device, the test piece includes a first side and a second side, the connection between the first side and the second side is the R-zone, the angle between the first side and the second side is 60°~120°, the angle of the first fixing member matches the angle of the first side, and the angle of the second fixing member matches the angle of the second side.

[0014] Preferably, the angle between the first side and the second side is 90°±2°.

[0015] In the aforementioned composite material R-zone impact point positioning and damage depth measurement device, the test piece fixing component further includes a first constraint and a second constraint. The first constraint is perpendicular to the first side of the test piece, and the second constraint is perpendicular to the second side. When the first constraint abuts against the first side, it provides vertical pressure to the first side, and when the second constraint abuts against the second side, it provides vertical pressure to the second side.

[0016] In the aforementioned composite material R-zone impact point positioning and damage depth measurement device, the first constraint member includes a handle and a rubber indenter, and the rubber indenter of the first constraint member abuts against the first side;

[0017] In the aforementioned composite material R-zone impact point positioning and damage depth measurement device, the second constraint member includes a handle and a rubber indenter, with the rubber indenter of the second constraint member abutting against the second side.

[0018] In the aforementioned composite material R-zone impact point location and damage depth measurement device, the length of the R-zone of the test piece is L, the first region of the R-zone is the region 1 / 10L to 1 / 4L away from the first edge of the R-zone, and the second region of the R-zone is the region 1 / 10L to 1 / 4L away from the second edge of the R-zone.

[0019] The aforementioned composite material R-zone impact point location and damage depth measurement device includes two usage methods: impact point location and damage depth measurement. The impact point location usage method includes the following steps:

[0020] Step 1.1: Contact the first region of the R area of ​​the test piece with the dial indicator;

[0021] Step 1.2: Displace the test piece and the dial indicator in the X-axis direction, the X-axis direction being perpendicular to the longitudinal axis of the R region. The point where the dial indicator reading is the lowest during the movement is marked as point A.

[0022] Step 1.3: Displace the test piece and the dial indicator in the Y-axis direction, the Y-axis direction being parallel to the longitudinal axis of the R region, so that the second region of the R region contacts the dial indicator, and move the test piece in the opposite direction along the X-axis direction. During the movement, the point where the dial indicator reading is the smallest is marked as point B.

[0023] Step 1.4: Connect points A and B and extend the line to the length of the entire R zone to form a line segment. The midpoint of the line segment is the impact point.

[0024] The method for measuring damage depth includes the following steps:

[0025] Step 2.1: Position the dial indicator directly over point A of the test specimen;

[0026] Step 2.2: Displace the test piece and the dial indicator so that the dial indicator moves from facing point A to facing point B, and record the maximum value of the dial indicator during this process as S1;

[0027] Step 2.3: Displace the test piece and the dial indicator in opposite directions, so that the dial indicator moves from facing point B to facing point A, and record the maximum value of the dial indicator during this process as S2;

[0028] Step 2.4, the impact damage depth value is the average of S1 and S2.

[0029] By employing the above technical solution, the present invention has at least the following advantages:

[0030] 1) This invention provides a device for locating impact points and measuring damage depth in the R region of composite materials, based on the structural characteristics of the test specimens in the R region. This device can realize the location of impact points and the measurement of the depth of impact damage pits in the R region impact damage introduction test.

[0031] 2) The present invention uses a dial indicator to determine the location of the impact point and measure the impact damage pit. The structure is very simple and the operation is very convenient.

[0032] 3) The test specimen fixing component of the present invention can fix the test specimen through the combined action of the first fixing component and the second fixing component, thus meeting the requirements of the impact test specimen constraint method.

[0033] 4) The test piece fixing member of the present invention, through the first constraint member and the second constraint member, can prevent the test piece from moving along the vertical direction of the straight edge during the impact process.

[0034] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the composite material R-zone impact point location and damage depth measurement device of the present invention;

[0036] Figure 2 This is a schematic diagram of the structure of the test piece of the present invention;

[0037] Figure 3 This is a schematic diagram of the structure of the first track of the present invention;

[0038] Figure 4 This is a partial cross-sectional view of the first track of the present invention;

[0039] Figure 5 This is another schematic diagram of the structure of the first track of the present invention;

[0040] Figure 6 This is a schematic diagram of the structure of the second track of the present invention;

[0041] Figure 7 This is a physical diagram of the installation of the test specimen and the test specimen fixing component of the present invention. Detailed Implementation

[0042] To further illustrate the technical means and effects of the present invention in achieving the intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0043] like Figure 1-6The composite material R-zone impact point location and damage depth measurement device shown includes a base 1, a bracket 2, a support arm 3, a support plate 4, and a test piece fixing component. A groove 10 is provided on the base 1, and at least one threaded hole is provided on the side wall of the groove 10, with an adjusting bolt 100 installed in the threaded hole. A bracket 2 is provided on the base 1; a support arm 3 is provided on the bracket 2, and the support arm 3 can move up and down along the bracket 2. A dial indicator 6 is provided on the support arm 3. The support plate 4 is disposed in the groove 10, and the free end of the adjusting bolt 100 abuts against the support plate 4 to achieve [the desired effect]. The support plate 4 is fixed; the test piece fixing member is used to fix both ends of the test piece, and the test piece fixing member is set on the support plate 4. The dial indicator 6 is directly opposite the R region of the test piece; and is configured such that: in the first state, the dial indicator 6 is directly opposite the first area of ​​the R region of the test piece; in the second state, the dial indicator 6 is directly opposite the second area of ​​the R region of the test piece; the dial indicator 6 and the test piece can be displaced along the X-axis and Y-axis directions, the X-axis direction and the X-axis opposite direction are perpendicular to the longitudinal axis direction of the R region, and the Y-axis direction is parallel to the longitudinal axis direction of the R region.

[0044] This invention uses a dial indicator 6 to determine the impact location of the R-zone test specimen. Since R-zone impact requires impact at the highest point of the R-zone arc, this invention selects the midpoint of the two vertices as the impact point. The first step is to select the weakest point of the test specimen as the impact point. Because the weakest point is more prone to delamination or fiber breakage, test specimens meeting the damage depth requirements still need to undergo subsequent mechanical property tests (such as residual strength tests). Therefore, the impact damage depth value obtained by the method of this invention meets the impact damage requirements in the aerospace field. Due to the characteristics of the R-zone test specimen, the vertices of the R-zone test specimen are the weakest points. Using the midpoint of the two vertices as the impact point allows the highest point of the R-zone of the conforming material to be found. Determining the impact point through the midpoint of the two vertices is a secondary confirmation of the vertices of the R-zone. This avoids errors in vertices due to the test specimen itself (such as local protrusions or depressions) and also avoids the influence of delamination damage when measuring the depth of the pit.

[0045] By using a dial indicator 6 to find the lowest value point in two regions (i.e., the first region and the second region) along the width of region R, the vertex of region R is located and used as the impact point. This invention considers the structural characteristics of the test specimen in region R; since region R is a continuous arc-shaped area, finding the vertex of the first and second regions essentially determines the range of the vertex. The device for determining the impact point using a dial indicator 6 in this invention has a very simple structure and is very convenient to operate.

[0046] The dial indicator 6 is set perpendicular to the R zone, the length of the R zone is L (generally 80~150mm), the first area of ​​the R zone is the area 1 / 10~1 / 4 L away from the first edge of the R zone, and the second area of ​​the R zone is the area 1 / 10~1 / 4 L away from the second edge of the R zone.

[0047] Taking a test piece with a width of 150mm (i.e., the length of the R region is 150mm) as an example, the specific locations of the first and second regions will be further explained. The first region is located 15mm to 37.5mm from the first edge of the test piece, and the second region is located 15mm to 37.5mm from the second edge of the test piece.

[0048] Since the dent depth at the impact point is a relative concept, calculated using the initial undamaged vertex as a reference, the dent depth is the value of the indentation. Based on existing experimental data, in addition to dents, impact points also exhibit delamination damage, which extends along the width of the specimen. The furthest extension reaches 1 / 4 L from the edge. Due to this delamination extension, the initial state of the specimen's vertex is altered, making it unsuitable as a reference point for dent measurement. Furthermore, the edge of the specimen is also unsuitable as a reference point. Therefore, the first region of the R zone is defined as the area 1 / 10 to 1 / 4 L from the first edge of the R zone, and the second region of the R zone is defined as the area 1 / 10 to 1 / 4 L from the second edge of the R zone.

[0049] In specifically implementing the solution that "the dial indicator 6 and the test piece can undergo displacement along the X-axis and Y-axis directions," the present invention specifically designed two implementation schemes:

[0050] Option 1:

[0051] The movement of the bracket 2 and the support arm 3 drives the movement of the dial indicator 6, thereby enabling displacement of the dial indicator 6 and the test piece along the X-axis and Y-axis directions. Specifically, a first track 7 is provided on the bracket 2, and the support arm 3 can move along the first track 7 to achieve the opposite movement of the dial indicator 6 along the X-axis and X-axis directions; a second track 8 is provided on the base 1, and the lower end of the bracket 2 can move on the second track 8 to achieve the opposite movement of the dial indicator 6 along the Y-axis and Y-axis directions.

[0052] In this embodiment, as Figure 3 and Figure 4As shown, the first track 7 can be in the form of a limiting ring 70. In this configuration, the support arm 3 is disposed within the limiting ring 70, which has a threaded through hole. A limiting bolt 71 is disposed within the threaded through hole, and the limiting bolt 71 abuts vertically against the side of the support arm 3. When the limiting bolt 71 abuts against the support arm 3, the support arm 3 remains stationary. When the limiting bolt 71 is not abutting against the support arm 3, the support arm 3 can move back and forth. This allows the dial indicator 6 to move within the first region of the test piece to find the first vertex, and the dial indicator 6 to move within the second region of the test piece to find the second vertex during the vertex-finding process.

[0053] As a possible implementation method, such as Figure 5 As shown, the first track 7 can also be in the form of a threaded limiting ring 72. The threaded limiting ring 72 includes an internal thread portion 722 and a mounting base 721. The internal thread portion 722 can rotate on the mounting base 721. A strip groove is provided on the base 1. The internal thread portion 722 is rotatably engaged with one end of the support arm 3. A protrusion is provided on the support arm 3. The protrusion slides in the strip groove, so that when the internal thread portion 722 rotates, the back-and-forth movement of the internal thread portion 722 can drive the support arm 3 to move back and forth (due to the action of the strip groove and the protrusion, the support arm 3 only moves in a straight line). In this way, in order to realize the electric operation mode of the composite material R-zone impact point positioning and damage depth measurement device shown, the composite material R-zone impact point positioning and damage depth measurement device also includes a first motor. The first motor is electrically connected to the internal thread portion 722. The first motor is used to drive the internal thread portion 722 to rotate, so that the support arm 3 moves in the X-axis direction (straight line movement).

[0054] In this embodiment, the second track 8 is a straight track, specifically a grooved track 10, and the cross-section of the track on the base 1 is as follows. Figure 6 As shown, the lower end of the bracket 2 is provided with a sliding protrusion 80 that matches the track of the groove 10. The sliding protrusion 80 can slide within the track of the groove 10 and can keep the bracket 2 in a vertical state. When the bracket 2 slides, the dial indicator 6 can move from the first region to the second region of the test piece, or from the second region to the first region. In order to realize the electric operation mode of the composite material R-zone impact point positioning and damage depth measurement device shown, the composite material R-zone impact point positioning and damage depth measurement device also includes a second motor, and the first motor is used to drive the bracket 2 to move along the Y-axis direction.

[0055] The second option:

[0056] The movement of the support plate 4 allows the dial indicator 6 and the test piece to move along the X-axis and Y-axis. The groove 10 on the base 1 serves as a sliding groove 40 for the support plate 4. When the adjusting bolt 100 is loose, the support plate 4 can move along the Y-axis (including the Y-direction and its opposite) within the groove 10 on the base 1. The support plate 4 has a sliding groove 40 oriented along the X-axis. A through hole is provided on the test piece fixing member, and a fixing bolt is installed within the through hole. The fixing bolt passes through the through hole and the sliding groove 40 to adjust and fix the position of the test piece fixing member. When the fixing bolt is loose, the test piece fixing member drives the test piece to move along the X-axis (including the X-direction and its opposite).

[0057] The test piece fixing component is fixed to the base 1 by fixing bolts, which facilitates the movement of the test piece and also makes it easy to replace the test piece fixing component.

[0058] In the above specific embodiments, both the first and second schemes can achieve relative displacement between the dial indicator 6 and the test piece, thereby enabling the use of the dial indicator 6 to measure the apex of the R zone. The impact point positioning method includes the following steps: Step 1.1, bringing the first region of the R zone of the test piece into contact with the dial indicator 6; Step 1.2, displacing the test piece and the dial indicator 6 in the X-axis direction, the X-axis direction being perpendicular to the longitudinal axis of the R zone, and marking the point with the smallest reading of the dial indicator 6 during the movement as point A; Step 1.3, displacing the test piece and the dial indicator 6 in the Y-axis direction, the Y-axis direction being parallel to the longitudinal axis of the R zone, bringing the second region of the R zone into contact with the dial indicator 6, and moving the test piece in the opposite direction along the X-axis direction, marking the point with the smallest reading of the dial indicator 6 during the movement as point B; Step 1.4, connecting points A and B and extending the line to the entire length of the R zone to form a line segment, the midpoint of which is the impact point. In practice, the test piece can be manually moved from the support plate 4 to a position near the side of the dial indicator 6, below it, with the dial indicator 6 in contact with the R zone. The test piece can then be moved back and forth by rotating the R zone positioning adjustment bolt 100, displaying a continuously changing value on the dial indicator 6. The vertex of the R zone is marked as point A. The other side of the test piece can then be manually moved to the underside of the dial indicator 6, with the dial indicator 6 in contact with the R zone. The test piece can then be moved back and forth by rotating the R zone positioning adjustment bolt 100, displaying a continuously changing value on the dial indicator 6. The vertex of the R zone is marked as point A. A line connecting points A and B can be drawn using a marker and extended to the entire width of the test piece; the point in the middle of the width on the line connecting A and B is the impact point. Alternatively, a computer program can drive the first and second motors to move the support 2 and the support arm 3, thereby moving the dial indicator 6 to locate the impact point.

[0059] After locating the impact point of the test specimen, an impact testing machine can be used to conduct the impact test. The support base of this invention is very easy to disassemble, so during the impact test, the support base and the test specimen can be placed together into the impact testing machine. This invention mounts the test specimen to the support base via the test specimen fixing member. The fixing member constrains the deformation of the test specimen along its straight edge during impact. Furthermore, a groove 10 matching the external dimensions of the test specimen can be provided on the base 1. The bottom plane of the groove 10 contacts and abuts against the test specimen, further providing constraint force. The test specimen, the fixing member, and the support base are placed together into a standard impact testing machine. The testing machine is positioned so that the impact point is directly below the punch of the standard drop hammer impact testing machine. The support base is fixed to the base 1 of the standard impact testing machine. The drop hammer is released to impact the test specimen, thus introducing damage to the test specimen.

[0060] After the impact test, the composite material R-zone impact point positioning and damage depth measurement device of the present invention can also measure the damage depth of the test piece. The specific steps for measuring the damage depth are as follows: Step 2.1, align the dial indicator 6 with point A of the test piece; Step 2.2, displace the test piece and the dial indicator 6 so that the dial indicator 6 moves from being aligned with point A to being aligned with point B, and record the maximum value of the dial indicator 6 during this process as S1; Step 2.3, displace the test piece and the dial indicator 6 in the opposite direction so that the dial indicator 6 moves from being aligned with point B to being aligned with point A, and record the maximum value of the dial indicator 6 during this process as S2; Step 2.4, the impact damage depth value is the average of S1 and S2. In practice, the test piece, its fixing component, and support base are removed together after the impact test. Then, these components are placed back into the composite material R-zone impact point positioning and damage depth measurement device. The support base is placed in the groove 10 of the base 1. The support base can be manually pushed to move the dial indicator 6's pin along a path coinciding with the line connecting points A and B on the test piece, from point A to point B. The maximum value S1 of the dial indicator 6 during this movement is recorded. Then, the support base is pushed again to move the dial indicator 6's pin along the same path, from point B to point A, and the maximum value S2 of the dial indicator 6 during this movement is recorded. The average of S1 and S2 is the impact damage depth value. Alternatively, a computer program can drive the first and second motors to move the bracket 2 and the support arm 3, thereby moving the dial indicator 6 to measure the damage depth of the test piece.

[0061] Furthermore, to achieve the constraint capability of the test specimen, this embodiment further designs the test specimen fixing component. The test specimen fixing component includes a first fixing component 51 and a second fixing component 52. The first fixing component 51 is used to fix a first side of the test specimen, and the second fixing component 52 is used to fix a second side of the test specimen. Specifically: the first fixing component 51 includes two opposing plates and a connecting portion connecting the two plates. The first side is located between the two plates, and one of the plates has at least one threaded hole. A bolt (in this embodiment, the bolt is perpendicular to the first side) is installed in the threaded hole. When tightened, the bolt abuts against the first side to fix the first side. The second fixing component 52 includes two opposing plates and a connecting portion connecting the two plates. The second side is located between the two plates, and one of the plates has at least one threaded hole. A bolt (in this embodiment, the bolt is perpendicular to the second side) is installed in the threaded hole. When tightened, the bolt abuts against the second side, pressing the test specimen against the second fixing component 52. Simultaneously, the clamping force provides friction to ensure that the test specimen does not shift. This achieves the fixation of the second side. This method not only facilitates the installation of the test piece but also provides reliable fastening force. More importantly, it prevents damage to the test piece. The accompanying drawings of this embodiment show a specific configuration where the first fixing member 51 has 6 threaded holes and 6 bolts. The number of threaded holes (bolts) can also be 1, 2, 3, 4, 5, or more than 6. The bolts only need to be sufficient to fix the test piece.

[0062] The test piece includes a first side and a second side, the connection between the first side and the second side is the R region, and the angle between the first side and the second side is generally 90°±2°.

[0063] As a possible implementation, the angle between the first side and the second side can be any value between 30° and 120°. In this implementation, simply matching the angles of the first fixing member 51 and the second fixing member 52 with those of the test piece is sufficient to fix the first and second sides of the test piece. Specifically, the first fixing member 51 is matched with the angle of the first side, and the second fixing member 52 is matched with the angle of the second side.

[0064] The device of the present invention can adjust the position of the support arm 3 and the dial indicator 6 according to the different sizes of the test specimen and the different angles formed by the first side and the second side.

[0065] To further enhance the constraint capability of the test specimen fixing component on the test specimen, the test specimen fixing component also includes a first constraint component and a second constraint component. The first constraint component is perpendicular to a first side of the test specimen, and the second constraint component is perpendicular to a second side. When the first constraint component abuts against the first side, it provides vertical pressure to the first side; when the second constraint component abuts against the second side, it provides vertical pressure to the second side. Specifically, the first constraint component includes a handle and a rubber indenter, with the rubber indenter abutting against the first side; the second constraint component also includes a handle and a rubber indenter, with the rubber indenter abutting against the second side. Since the test specimen needs to be constrained to deform outwards and translate along the straight edge direction during the impact process, the handle with the rubber indenter presses the test specimen perpendicular to the straight edge, preventing the test specimen from shifting along the straight edge perpendicularly during the impact, thus completing the fixation of the test specimen.

[0066] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A device for locating impact points and measuring damage depth in the R-zone of a composite material, characterized in that, include: A base, having a groove on the base, at least one threaded hole on the side wall of the groove, and an adjusting bolt inside the threaded hole; A bracket is provided on the base; A support arm is provided on the bracket, the support arm can move up and down along the bracket, and a dial indicator is provided on the support arm; A support plate is provided in the groove, and the free end of the adjusting bolt abuts against the support plate to fix the support plate. The test specimen holder is used to fix both ends of the test specimen. The test specimen holder is set on the support plate, and the dial indicator is directly opposite the R area of ​​the test specimen. And configure it as follows: In the first state, the dial indicator is directly facing the first region of the R zone of the test specimen; In the second state, the dial indicator is positioned directly over the second region of the R zone of the test specimen; The dial indicator and the test piece can be displaced in the X-axis and Y-axis directions. The X-axis direction is perpendicular to the longitudinal axis of the R-zone, and the Y-axis direction is parallel to the longitudinal axis of the R-zone. The X-axis direction includes both the X-direction and the opposite direction of the X-direction, and the Y-axis direction includes both the Y-direction and the opposite direction of the Y-direction. The length of the R region of the test piece is L. The first region of the R region is the region located 1 / 10L to 1 / 4L away from the first edge of the R region. The second region of the R region is the region located 1 / 10L to 1 / 4L away from the second edge of the R region. The composite material R-zone impact point location and damage depth measurement device includes two usage methods: impact point location and damage depth measurement. The impact point location method includes the following steps: Step 1.1: Contact the first region of the R area of ​​the test piece with the dial indicator; Step 1.2: Displace the test piece and the dial indicator in the X-axis direction, where the X-axis direction is perpendicular to the longitudinal axis of the R region. The point where the dial indicator reading is the lowest during the movement is marked as point A. Step 1.3: Displace the test piece and the dial indicator in the Y-axis direction, the Y-axis direction being parallel to the longitudinal axis of the R region, so that the second region of the R region contacts the dial indicator, and move the test piece in the opposite direction along the X-axis direction. During the movement, the point where the dial indicator reading is the smallest is marked as point B. Step 1.4: Connect points A and B and extend the line to the length of the entire R zone to form a line segment. The midpoint of this line segment is the impact point.

2. The composite material R-zone impact point location and damage depth measurement device according to claim 1, characterized in that, A first track is provided on the bracket, and the support arm can move along the first track to realize the movement of the dial indicator along the X-axis direction; A second track is provided on the base, and the lower end of the bracket can move on the second track to enable the dial indicator to move along the Y-axis.

3. The composite material R-zone impact point location and damage depth measurement device according to claim 2, characterized in that, It also includes a first motor and a second motor. The first motor is used to drive the support arm to move along the X-axis direction; The first motor is used to drive the bracket to move along the Y-axis.

4. The composite material R-zone impact point location and damage depth measurement device according to claim 1, characterized in that, With the adjusting bolt in a relaxed state, the support plate can move along the X-axis. A sliding groove is provided on the support plate, and the sliding groove is arranged in the Y-axis direction. A through hole is provided on the test piece fixing member, and a fixing bolt is provided in the through hole. The fixing bolt passes through the through hole and the sliding groove to adjust and fix the position of the test piece fixing member.

5. The composite material R-zone impact point location and damage depth measurement device according to claim 1, characterized in that, The test specimen fixing component includes a first fixing component and a second fixing component. The first fixing component is used to fix a first side of the test specimen, and the second fixing component is used to fix a second side of the test specimen, wherein: The first fastener includes two plates arranged opposite each other and a connecting part connecting the two plates. The first side is disposed between the two plates. At least one threaded hole is provided on one of the plates, and a bolt is provided in the threaded hole. The bolt can abut against the first side when tightened to fix the first side. The second fastener includes two plates arranged opposite each other and a connecting part connecting the two plates. The second side is disposed between the two plates. At least one threaded hole is provided on one of the plates, and a bolt is provided in the threaded hole. The bolt can abut against the second side when tightened to fix the second side.

6. The composite material R-zone impact point location and damage depth measurement device according to claim 5, characterized in that, The test piece includes a first side and a second side, the connection between the first side and the second side is the R region, the angle between the first side and the second side is 60°~120°, the angle of the first fixing member matches the angle of the first side, and the angle of the second fixing member matches the angle of the second side.

7. The composite material R-zone impact point location and damage depth measurement device according to claim 5, characterized in that, The test specimen fixing component further includes a first constraint member and a second constraint member. The first constraint member is perpendicular to a first side of the test specimen, and the second constraint member is perpendicular to a second side. When the first constraint member abuts against the first side, it provides vertical pressure to the first side, and when the second constraint member abuts against the second side, it provides vertical pressure to the second side.

8. The composite material R-zone impact point location and damage depth measurement device according to claim 7, characterized in that, The first constraint member includes a handle and a rubber pressure head, with the rubber pressure head of the first constraint member abutting against the first side; The second constraint member includes a handle and a rubber pressure head, with the rubber pressure head of the second constraint member abutting against the second side.

9. The composite material R-zone impact point location and damage depth measurement device according to claim 1, characterized in that, The method for measuring damage depth includes the following steps: Step 2.1: Position the dial indicator directly over point A of the test specimen; Step 2.2: Displace the test piece and the dial indicator so that the dial indicator moves from facing point A to facing point B, and record the maximum value of the dial indicator during this process as S1; Step 2.3: Displace the test piece and the dial indicator in opposite directions, so that the dial indicator moves from facing point B to facing point A, and record the maximum value of the dial indicator during this process as S2; Step 2.4, the impact damage depth value is the average of S1 and S2.

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