Foaming adhesive film penetrability testing tool and testing method

Abstract

The invention discloses a foaming adhesive film penetrability testing tool and a testing method. The testing tool comprises a base; the testing platform is arranged on the base through a plurality of adjusting supports and is used for bearing a foaming adhesive film to be tested; the calibration mechanism is used for detecting the levelness of the test platform; the bracket is arranged on the base; and the load loading mechanism is arranged on the bracket and is used for applying a load to the to-be-tested foaming adhesive film. Quantitative test characterization of the penetrability of the foaming adhesive film is achieved, dependence on the skill level of an operator can be effectively reduced, meanwhile, the stability and reproducibility of a test result can be improved, and the method is suitable for penetrability tests of various types of adhesive films and other flexible materials.

Description

Technical Field

[0001] The invention belongs to the technical field of composite material penetration testing, and in particular relates to a foam film penetration testing tool and a testing method. Background Art

[0002] Honeycomb sandwich structures have the characteristics of high strength, large bending stiffness and low density, and are widely used in aircraft and helicopter structures, such as wall panels, tail beams, antenna radomes, cabin floors, etc. However, due to the limitation of honeycomb size, in the molding process of large-size or large-curvature components of sandwich structures, the honeycomb core usually needs to be spliced ​​to meet the size and configuration requirements. There are three main splicing methods commonly used: direct splicing, film + aramid thread sewing, and sheet foam film splicing. Among them, the honeycomb spliced ​​with foam film has the best bending performance of the sandwich structure and is widely used in actual production processes.

[0003] Based on the special requirements of honeycomb splicing, foam adhesive needs to have a certain bonding strength and penetration, which is conducive to improving the strength of honeycomb splicing. However, the current performance evaluation of foam adhesive is still based on traditional testing methods, such as expansion rate, single lap shear and other bonding performance characterizations. There is a lack of evaluation methods for the penetration performance of foam adhesive films under real production conditions. Summary of the invention

[0004] In order to address the deficiencies in the prior art, the present invention provides a foam film penetration test tool and test method, which realizes the quantitative test characterization of the penetration performance of the foam film, can effectively reduce the dependence on the operator's skill level, and at the same time can improve the stability and reproducibility of the test results, and is suitable for penetration tests of various types of films and other flexible materials.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: In a first aspect, a foam film penetration test tool is provided, comprising: a base; a test platform mounted on the base via a plurality of adjustment supports and used to support the foam film to be tested; a calibration mechanism for detecting the horizontality of the test platform; a bracket arranged on the base; and a load loading mechanism arranged on the bracket and used to apply a load to the foam film to be tested.

[0006] Furthermore, the calibration mechanism comprises: a calibration link and a bar level installed on the calibration link; the calibration link is installed on the base via a calibration support, and the calibration link is hinged to the calibration support.

[0007] Furthermore, one end of the calibration rod extends above the test platform, and the distance d from the center of the test platform to the calibration rod satisfies: r1<d≤r2, wherein r1 represents the radius of the contact area between the load loading mechanism and the foam film to be tested, and r2 represents half of the radius of the test platform.

[0008] Furthermore, the bracket includes a loading platform parallel to the base, and a plurality of legs connected between the base and the loading platform; a sleeve with a vertical axis passes through the loading platform and is fixedly connected to the loading platform.

[0009] Furthermore, the center of the base coincides with the center of the loading platform, and a plurality of the legs are evenly distributed around the centers of the base and the loading platform.

[0010] Furthermore, the load loading mechanism comprises a pressure rod, which is installed in a sleeve through a ball bushing; one end of the pressure rod is provided with a load loading rod for carrying a weight, and the other end is provided with a test pressure head for abutting against the foam film to be tested.

[0011] Furthermore, the compression rod is provided with a plurality of weight-reducing holes.

[0012] Furthermore, a pointer is provided on the pressure rod, and a scale line for marking the moving distance of the load loading mechanism is provided on the sleeve.

[0013] Furthermore, an operating handle is provided on the pressure rod.

[0014] In a second aspect, a foam film penetration test method is provided, based on the foam film penetration test tool described in the first aspect, the method comprising: first placing the foam film to be tested on a test platform, and then adjusting the horizontality of the test platform by a calibration mechanism; after adjusting the horizontality of the test platform, installing a load loading mechanism equipped with a set weight on a bracket, and recording the position of the test pressure head of the load loading mechanism when it just contacts the foam film to be tested, and the distance L moved by the load loading mechanism under the action of gravity after a set time; the distance L is used to evaluate the penetration performance of the foam film under a set load and a set time.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention realizes quantitative test characterization of the penetration performance of foam films by designing the specific structure of the foam film penetration test tooling, arranging a base, a test platform for carrying the foam film to be tested, a load loading mechanism for applying a load to the foam film to be tested, etc., which can effectively reduce the dependence on the skill level of the operator and at the same time improve the stability and reproducibility of the test results, and is suitable for penetration tests of various types of films and other flexible materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional structural schematic diagram of a foam film penetration test tool provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of the planar structure of a foam film penetration test tool provided by an embodiment of the present invention; In the figure: 10, base; 11, loading platform; 12, support leg; 13, sleeve; 14, test starting position; 15, knob; 20, test platform; 30, calibration rod; 31, strip level; 32, calibration support; 40, pressure rod; 41, ball bushing; 42, load loading rod; 43, test pressure head; 44, pointer; 45, operating handle. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0018] Embodiment 1 like Figure 1 , Figure 2 As shown, a foam film penetration test tool includes a base 10; a test platform 20 installed on the base 10 through a plurality of adjustment supports and used to carry the foam film to be tested; a calibration mechanism for detecting the horizontality of the test platform 20; a bracket arranged on the base 10; and a load loading mechanism arranged on the bracket and used to apply a load to the foam film to be tested.

[0019] The calibration mechanism includes: a calibration link 30 and a strip level 31 installed on the calibration link 30; the calibration link 30 is installed on the base 10 through a calibration support 32, and the calibration link 30 is hinged to the calibration support 32. One end of the calibration link 30 extends above the test platform 20, and the distance d from the center of the test platform 20 to the calibration link 30 satisfies: r1<d≤r2, where r1 represents the radius of the contact area between the load loading mechanism and the foam film to be tested, and r2 represents half of the radius of the test platform 20. By limiting the distance from the center of the test platform 20 to the calibration link 30, sufficient contact between the calibration link 30 and the test platform 20 can be ensured; the strip level 31 is used to indicate the horizontality of the calibration link 30. When the calibration link 30 and the test platform 20 are in sufficient contact, the horizontality of the test platform 20 can be further calibrated through the calibration link 30.

[0020] The test platform 20 is installed on the base 10 through four adjustment supports, and a knob 15 is provided on the adjustment support. By adjusting the knob 15, the upper and lower positions of the test platform 20 in different directions can be adjusted, and then cooperated with the calibration mechanism to complete the adjustment of the horizontality of the test platform 20.

[0021] The bracket includes a loading platform 11 parallel to the base 10, three legs 12 connected between the base 10 and the loading platform 11; a sleeve 13 with a vertical axis passes through the loading platform 11 and is fixedly connected to the loading platform 11. The center of the base 10 coincides with the center of the loading platform 11, and the three legs 12 are evenly distributed around the center of the base 10 and the loading platform 11. In the present invention, by setting the three legs 12 evenly distributed around the center of the base 10 and the loading platform 11 and jointly supporting between the base 10 and the loading platform 11, the stability and bearing capacity of the loading platform 11 can be improved. At the same time, sufficient operating space can be reserved between the base 10 and the loading platform 11 to improve the convenience of operation.

[0022] The load loading mechanism includes a pressure rod 40, which is installed in the sleeve 13 through a ball bushing 41; a load loading rod 42 for carrying a weight is provided at one end of the pressure rod 40, and a test pressure head 43 for abutting against the foam film to be tested is provided at the other end. The friction between the inner wall of the sleeve 13 and the pressure rod 40 can be reduced by providing the ball bushing 41, so as to ensure that the force acting on the foam film to be tested during the test is more accurate.

[0023] The pressure rod 40 is provided with a plurality of weight-reducing holes. Since the weight acting on the foam film to be tested during the test is the sum of the weight of the load loading mechanism itself and the weight of the weight on the load loading rod 42, the weight of the load loading mechanism itself can be reduced as much as possible by providing the weight-reducing holes, thereby expanding the detection range of the entire device and improving the detection accuracy. The area occupied by each weight-reducing hole does not exceed 50% of the surface area of ​​the pressure rod 40, which can ensure that the pressure rod 40 still has sufficient strength and stability after the weight-reducing holes are provided.

[0024] A pointer 44 is provided on the pressure rod 40, and a scale line for marking the moving distance of the load loading mechanism is provided on the sleeve 13. By recording the scale indicated by the pointer 44 at the beginning of the test and the scale indicated by the pointer 44 at the end of the test, the moving distance of the load loading mechanism can be calculated, and the moving distance is used to evaluate the penetration performance of the foam film under a set load and a set time.

[0025] An operating handle 45 is provided on the pressure rod 40. The operating handle 45 is used to lift or lower the entire load loading mechanism before and after the test.

[0026] The method of using the foam film penetration test tool of the present invention is as follows: (1) Place the base 10 and the bracket of the tooling on a calibrated marble platform; (2) Place the foam film to be tested on the test platform 20 and adjust the knob 15 below it until the bubble of the bar level 31 on the calibration connecting rod 30 is centered; (3) Insert the pressure rod 40 into the sleeve 13, lift the pressure rod 40 by operating the handle 45, ensure that the test pressure head 43 does not contact the foam film to be tested, and put a weight or other heavy object on the load loading rod 42 according to the required weight; (4) Gently lower the pressure rod 40 by operating the handle 45 until the pointer 44 reaches the 0 mark (i.e., the test starting position 14) (at this time, the test pressure head 43 just contacts the upper surface of the foam film to be tested), release the operating handle 45, start timing, and allow the test pressure head to penetrate the film under the action of a given load; (5) When the required load application time is reached, the position of the pointer 44 is read and the downward movement of the test pressure head 43 is recorded as the film penetration performance.

[0027] The material of the test tool of the present invention is stainless steel or aviation aluminum, etc., which is low in cost, simple in structure, easy to manufacture and carry. By adjusting the upper and lower positions of the test platform, it is ensured that when the test pressure head starts to contact the film to be tested, the pointer is always at the 0 scale line, which reduces the error of human judgment and improves the stability and reproducibility of the test results. At the same time, it is convenient for inexperienced personnel to operate and reduces the requirements for the operator's hands-on ability. The test method of the present invention is simple in principle and has a wide range of uses. It can be used for multi-load and multi-type flexible material penetration performance testing.

[0028] Embodiment 2 Based on the foam film penetration test tool described in Example 1, this embodiment provides a foam film penetration test method, including: First, place the foam film to be tested on the test platform 20, and then adjust the levelness of the test platform 20 through the calibration mechanism; After adjusting the horizontality of the test platform 20, the load loading mechanism equipped with a set weight is installed on the bracket, and the position of the test pressure head 43 of the load loading mechanism when it just contacts the foam film to be tested, as well as the distance L moved by the load loading mechanism under the action of gravity after a set time are recorded; the distance L is used to evaluate the penetration performance of the foam film under a set load and a set time.

[0029] The following is a specific film test process to further explain the specific method of penetration test. Test environment requirements: temperature 23±2℃, humidity 50±10%.

[0030] Step 1: Place the base 10 and the bracket of the tooling on the calibrated marble platform and confirm that they are placed horizontally using a level; Step 2: Cut 3 pieces of LOCTITE EF 562 50M AERO film with a 50mm diameter sample block and lay them together in sequence, leaving the protective paper on the upper and lower surfaces; Step 3: Remove the protective film from the previous step, place it on the test platform 20, and adjust the knob 15 below it until the bubble of the bar level 31 on the calibration connecting rod 30 is centered; Step 4: insert the pressure rod 40 into the sleeve 13, lift the pressure rod 40 by operating the handle 45, ensure that the test pressure head 43 does not contact the film to be tested, and put a 90g weight (plus the pressure rod's own weight of 95g, a total of 185g) on ​​the load loading rod 42; Step 5: Hold the operating handle 45 and gently lower the pressure rod 40 until the pointer 44 on the pressure rod 40 indicates the 0 mark (i.e. the test starting position 14) (at this time, the test pressure head 43 just contacts the upper surface of the film to be tested), release the operating handle 45, start timing, and allow the test pressure head 43 to penetrate the film under the given load; Step 6: When the penetration time reaches (300±10) s, read the position of the pointer 44 and record the downward movement of the test pressure head 43 as the film penetration performance.

[0031] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A foam film penetration test tool, characterized in that: include: Base (10); A test platform (20) mounted on the base (10) via a plurality of adjustment supports and used to support the foam film to be tested; A calibration mechanism for detecting the horizontality of the test platform (20); A bracket arranged on the base (10); A load loading mechanism is arranged on the bracket and is used to apply a load to the foamed rubber film to be tested.

2. The foam film penetration test tool according to claim 1, characterized in that: The calibration mechanism comprises: a calibration link (30) and a bar-type level (31) mounted on the calibration link (30); the calibration link (30) is mounted on the base (10) via a calibration support (32), and the calibration link (30) is hinged to the calibration support (32).

3. The foam film penetration test tool according to claim 2, characterized in that: One end of the calibration connecting rod (30) extends above the test platform (20), and the distance d from the center of the test platform (20) to the calibration connecting rod (30) satisfies: r1<d≤r2, wherein r1 represents the radius of the contact area between the load loading mechanism and the foam film to be tested, and r2 represents half of the radius of the test platform (20).

4. The foam film penetration test tool according to claim 1, characterized in that: The bracket comprises a loading platform (11) parallel to the base (10), a plurality of legs (12) connected between the base (10) and the loading platform (11), and a sleeve (13) with a vertical axis that passes through the loading platform (11) and is fixedly connected to the loading platform (11).

5. The foam film penetration test tool according to claim 4, characterized in that: The center of the base (10) coincides with the center of the loading platform (11), and a plurality of the legs (12) are evenly distributed around the centers of the base (10) and the loading platform (11).

6. The foam film penetration test tool according to claim 4, characterized in that: The load loading mechanism comprises a pressure rod (40), wherein the pressure rod (40) is installed in the sleeve (13) via a ball bushing (41); one end of the pressure rod (40) is provided with a load loading rod (42) for carrying a weight, and the other end is provided with a test pressure head (43) for abutting against the foam film to be tested.

7. The foam film penetration test tool according to claim 6, characterized in that: The pressure rod (40) is provided with a plurality of weight-reducing holes.

8. The foam film penetration test tool according to claim 6, characterized in that: The pressure rod (40) is provided with a pointer (44), and the sleeve (13) is provided with a scale line for marking the moving distance of the load loading mechanism.

9. The foam film penetration test tool according to claim 6, characterized in that: An operating handle (45) is provided on the pressure rod (40).

10. A method for testing the penetration of a foam film, characterized in that: Based on the foam film penetration test tool according to any one of claims 1 to 9, the method comprises: First, place the foam film to be tested on the test platform (20), and then adjust the levelness of the test platform (20) by means of a calibration mechanism; After adjusting the horizontality of the test platform (20), a load loading mechanism equipped with a set weight is installed on the bracket, and the position of the test pressure head (43) of the load loading mechanism when it just contacts the foam film to be tested, as well as the distance L moved by the load loading mechanism under the action of gravity after a set time, are recorded; the distance L is used to evaluate the penetration performance of the foam film under the set load and set time.

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