Stress loading test device in extreme high and low temperature cycle test
By designing a stress loading test device suitable for extreme high and low temperature environments, and using Invar steel support and clamping frames, the problems of cumbersome operation and low testing efficiency of existing devices in extreme environments are solved, and stable stress loading and efficient batch testing of composite materials are realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SUZHOU LABORATORY
- Filing Date
- 2026-02-25
- Publication Date
- 2026-05-08
AI Technical Summary
Existing stress loading test equipment is difficult to apply stable stress to composite materials under extreme high and low temperature environments, and its operation is cumbersome, making it difficult to achieve batch testing and failing to meet the performance research needs under long-term service environments.
A stress loading test device for extreme high and low temperature cycling tests was designed. It adopts a support frame and clamping frame made of Invar steel, combined with a double-layer frame top and stabilizing block, and is equipped with an adjustable tension base and locking components to achieve stable clamping of the specimen and long-term stress retention. It is suitable for high and low temperature cycling test machines.
Maintaining structural stability under extreme high and low temperature environments ensures uniform stress distribution, improves testing efficiency and result reliability, and supports long-term performance studies.
Smart Images
Figure CN121994598A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of stress loading testing technology, and more specifically to a stress loading testing device for extreme high and low temperature cycling tests. Background Technology
[0002] In the aerospace field, the development of materials for space launch vehicle tanks is gradually shifting from traditional alloy materials to carbon fiber composites, which is an inevitable trend for achieving lightweight design. However, space launch vehicle tanks often face extreme environments during actual service, including complex mechanical loading conditions and extreme temperature environments such as ultra-low or high temperatures. In particular, under high and low temperature thermal fatigue conditions, composite materials may experience significant performance degradation due to thermo-mechanical coupling effects.
[0003] To study the performance changes of carbon fiber composites under extreme environments, it is typically necessary to apply stable stress to the material during high and low temperature cycling tests. Currently, the commonly used testing methods involve using mechanical testing equipment in conjunction with high and low temperature testing chambers. However, these devices have several limitations. First, existing equipment is difficult to adapt to extreme low-temperature environments (such as -180°C), resulting in test results that cannot accurately reflect the material's performance under real service conditions. Second, the structure of existing devices is usually relatively fixed, operation is cumbersome, and it is difficult to achieve batch testing of materials, thus limiting research efficiency. Furthermore, existing technologies lack sufficient stress retention capability under long-term low-temperature service environments, failing to meet the requirements for long-term stability testing of composite materials.
[0004] Therefore, achieving stable stress loading on composite material samples under extreme high and low temperature environments has become a major technical challenge in current research and is also key to promoting the practical application of composite material storage tanks. Developing a test device capable of conducting high and low temperature cycling tests within a range of -180℃ to 180℃ while maintaining stable stress loading is of great significance for revealing the failure mechanism of composite materials under extreme environments and evaluating their residual properties. Summary of the Invention
[0005] This invention provides a stress loading test apparatus for extreme high and low temperature cycling tests to solve the problem that existing stress loading test apparatuses cannot perform stress loading cyclic tests on composite materials at high and low temperatures.
[0006] The stress loading test apparatus for extreme high and low temperature cycling tests of the present invention adopts the following technical solution: A stress loading test apparatus for extreme high and low temperature cycling tests, comprising a support frame, a clamping frame, and a load-holding device; The support frame includes a frame top and support columns; two frame tops are provided, and the two frame tops are respectively fixedly installed at both ends of the support columns; the clamping frame includes a specimen clamp, a fixed base, and a tensile base, the fixed base being fixedly connected to one of the frame tops; the tensile base is movably installed on the other frame top, and the distance between the tensile base and the fixed base can be changed; two specimen clamps are provided, one of which is fixedly installed on the tensile base and the fixed base, and the specimen clamp is used to clamp the end of the specimen; the load-bearing device includes a fixed end, a tensile end, and a locking assembly, the fixed end being fixedly connected to the fixed base, and the tensile end being connected to the tensile base; the tensile end passes through the frame top and extends outward, and the end of the tensile end extending outside the frame top is the clamping end; the fixed end can be fixed on an external tensile testing machine, and the clamping end can be loaded by the external tensile testing machine; the locking assembly is used to lock the clamping end on the frame top.
[0007] Furthermore, the support column is a hollow rectangular Invar steel, and there are two support columns, which are distributed in parallel and spaced apart between the tops of the two frames.
[0008] Furthermore, the top of the frame is a type II Invar double-layer structure, the top of the frame is a hollow structure, and the top of the frame is connected to the support column by welding.
[0009] Furthermore, a stabilizing block is provided inside the top of the frame. The stabilizing block is made of solid Invar steel and is fixedly installed inside the middle of the top of the frame.
[0010] Furthermore, the specimen clamp has a clamping slot, and the end of the specimen can be inserted into the clamping slot. The specimen clamp is provided with a fixing bolt, which is used to fix the end of the specimen in the clamping slot.
[0011] Furthermore, a positioning pin is fixedly provided on the stretch base, and the positioning pin slides through the top of the frame.
[0012] Furthermore, the fixed end is fixedly connected to the fixed base, the fixed end passes through the top of the frame and extends outward, and the fixed end passes through the stabilizing block, and one end of the fixed end extending outside the top of the frame can be fixed on the external tensile testing machine.
[0013] Furthermore, the locking assembly includes two fixing rods, both of which are fixed on the tension base. The two fixing rods are distributed on both sides of the tension end. The fixing rods slide through the top of the frame. The outer side wall of the fixing rod is provided with a first threaded groove. A first nut can be screwed onto the fixing rod extending to the outside of the top of the frame.
[0014] Furthermore, the outer wall of the clamping end of the stretching end is provided with a second threaded groove, on which a second nut can be screwed.
[0015] Furthermore, the locking direction of the first nut is opposite to that of the second nut to form a bidirectional locking mechanism.
[0016] The beneficial effects of this invention are as follows: The stress loading test device for extreme high and low temperature cycling tests of this invention includes a support frame, a clamping frame, and a load-holding device. The support frame is made of Invar steel, whose low coefficient of thermal expansion and excellent dimensional stability ensure that the device maintains structural stability in extreme high and low temperature environments ranging from -180°C to +180°C, avoiding uneven stress distribution caused by thermal expansion and contraction. Furthermore, the installation of two fixing rods on the tension base and the setting of the tension end, along with the locking methods of the first and second nuts being set in opposite directions, achieves long-term stress retention in the specimen, facilitating performance studies under long-term service conditions. The device has a simple structure and is easy to operate, and can be used with a mature high and low temperature cycling test machine to achieve rapid batch testing, significantly improving testing efficiency. Through precise loading and locking design, it ensures uniform stress distribution in the specimen during testing, resulting in highly reliable and repeatable test results. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0018] Figure 1 This is a schematic diagram of the stress loading test apparatus for extreme high and low temperature cycling tests provided in an embodiment of the present invention; Figure 2 This is a side view of the stress loading test apparatus for extreme high and low temperature cycling testing provided in an embodiment of the present invention; Figure 3 for Figure 2 A cross-sectional view along the AA direction.
[0019] In the figure: 110, top of upper frame; 120, top of lower frame; 130, support column; 140, specimen clamp; 150, fixed base; 160, tension base; 170, stabilizing block; 210, first fixed shaft; 220, second fixed shaft; 230, fixed rod; 240, first nut; 250, second nut. Detailed Implementation
[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0021] The serial numbers assigned to components in this document, such as "first," "second," etc., are merely used to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages). In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.
[0022] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0023] like Figures 1 to 3 As shown in the embodiment of the present invention, the stress loading test device for extreme high and low temperature cycle testing includes a support frame, a clamping frame, and a load-holding device.
[0024] The support frame includes a frame top and a support column 130. There are two frame tops, which are arranged parallel to each other vertically. The upper frame top is called the upper frame top 110, and the lower frame top is called the lower frame top 120. The support column 130 is arranged vertically, and the upper and lower ends of the support column 130 are fixedly connected to the upper frame top 110 and the lower frame top 120, respectively.
[0025] The clamping frame includes a specimen clamp 140, a fixed base 150, and a tension base 160. The fixed base 150 is horizontally positioned between the top of the upper frame 110 and the top of the lower frame 120, and is fixed to the upper surface of the top of the lower frame 120. The tension base 160 is horizontally positioned between the top of the upper frame 110 and the top of the lower frame 120, and is movably connected to the lower surface of the top of the upper frame 110. The tension base 160 is directly above the fixed base 150, and the distance between the tension base 160 and the fixed base 150 can be changed.
[0026] Two specimen clamps 140 are provided. One specimen clamp 140 is fixedly installed on the upper surface of the fixed base 150, and the other specimen clamp 140 is fixedly installed on the lower surface of the tensile base 160. The specimen clamp 140 is used to clamp the end of the specimen. When the specimen is subjected to stress loading test, the two ends of the specimen are fixed on the two specimen clamps 140 respectively. Then, the tensile base 160 gradually moves away from the fixed base 150, thereby applying tensile stress to the specimen.
[0027] The load-bearing device includes a fixed end, a tensile end, and a locking assembly. The fixed end is fixedly connected to a fixed base 150. The tensile end is connected to a tensile base 160, passes through the top of the upper frame 110, and extends outward. The end of the tensile end extending outside the top of the upper frame 110 is the clamping end. The fixed end can be fixed to an external tensile testing machine, and the clamping end can be loaded by the external tensile testing machine. The locking assembly is used to lock the clamping end onto the top of the upper frame 110, ensuring that it remains stable when tensile stress is applied to the specimen.
[0028] In one embodiment, the support column 130 is a hollow rectangular Invar steel. There are two support columns 130, which are distributed in parallel between the tops of the upper frame 110 and the tops of the lower frame 120. Furthermore, the two support columns 130 are equidistant from the fixed base 150, ensuring that the support column 130 can maintain a stable shape when tensile stress is applied to the specimen. In addition, the Invar steel material has a low coefficient of thermal expansion and excellent dimensional stability, ensuring that the support column 130 can maintain structural stability in extreme high and low temperature environments from -180°C to +180°C.
[0029] In one embodiment, both the upper frame top 110 and the lower frame top 120 are Type II Invar double-layer structures, and both are hollow structures. The upper frame top 110 and the lower frame top 120 are fixedly connected to the support column 130 by welding. Similarly, Invar steel has a low coefficient of thermal expansion and excellent dimensional stability, ensuring that the upper frame top 110 and the lower frame maintain structural stability in extreme high and low temperature environments ranging from -180°C to +180°C.
[0030] In one embodiment, a stabilizing block 170 is provided inside both the top 110 of the upper frame and the top 120 of the lower frame. The stabilizing block 170 is made of solid Invar steel and is fixedly installed inside the middle of the top 110 of the upper frame or the top 120 of the lower frame. Furthermore, in order to prevent the top 110 of the upper frame or the top 120 of the lower frame from deforming when tensile stress is applied to the specimen, the vertical dimension of the stabilizing block 170 is processed to be equal to the vertical dimension inside the top 110 of the upper frame or the top 120 of the lower frame. After installation, the stabilizing block 170 increases the deformation resistance of the top 110 of the upper frame or the top 120 of the lower frame.
[0031] In one embodiment, the specimen clamp 140 has a clamping slot, into which the end of the specimen can be inserted. The specimen clamp 140 is provided with a fixing hole that passes through the clamping slot. When it is necessary to fix the end of the specimen to the specimen clamp 140, a fixing bolt is passed through the fixing hole, and a matching fixing nut is used to cooperate with the fixing bolt to fix the end of the specimen in the clamping slot. When it is necessary to replace the specimen, the operator can simply rotate the fixing nut to disassemble and assemble the specimen.
[0032] In one embodiment, a positioning pin is fixedly provided on the upper surface of the tensile base 160. The positioning pin is vertically positioned and slides through the top of the upper frame 110. When the tensile base 160 is not connected to an external tensile testing machine, in order to ensure that the tensile base 160 will not detach from the top of the upper frame 110 due to its own weight, the positioning pin is fixedly provided on the tensile base 160, and the positioning pin can ensure that the tensile base 160 is stably positioned directly above the fixed base 150.
[0033] In one embodiment, the fixed end is fixedly connected to the fixed base 150. The fixed end includes a first fixed plate and a first fixed shaft 210. The first fixed plate is fixedly attached to the lower surface of the fixed base 150, and the first fixed shaft 210 is fixedly connected to the lower surface of the first fixed plate. The first fixed shaft 210 passes through the top of the lower frame 120 and extends downward. At the same time, the first fixed shaft 210 passes through the stabilizing block 170 located inside the top of the lower frame 120. The end of the first fixed shaft 210 extending to the outside of the top of the lower frame 120 can be fixed on an external tensile testing machine.
[0034] In one embodiment, the locking assembly includes two fixing rods 230, and the tensioning end includes a second fixing plate and a second fixing shaft 220. The second fixing plate is fixedly attached to the upper surface of the tensioning base 160, and the second fixing shaft 220 is fixedly connected to the upper surface of the second fixing plate. The second fixing shaft 220 passes through the top of the upper frame 110 and also passes through a stabilizing block 170 located inside the top of the upper frame 110. Further, the second fixing shaft 220 located outside the top of the upper frame 110 serves as a clamping end. Both fixing rods 230 are vertically fixed on the upper surface of the tensioning base 160, and the two fixing rods 230 are distributed on both sides of the tensioning end, so the horizontal distance between the two fixing rods 230 and the second fixing shaft 220 is the same. Both fixing rods 230 slide through the top of the upper frame 110. The upper outer side wall of the fixing rod 230 is provided with a first threaded groove. The worker can thread a first nut 240 onto the fixing rod 230 above the top of the upper frame 110, thereby fixing the fixing rod 230 onto the top of the upper frame 110.
[0035] In one embodiment, the outer side wall of the upper part of the second fixed shaft 220 is provided with a second threaded groove, so that the operator can thread a second nut 250 onto the second fixed shaft 220 above the top 110 of the upper frame, thereby fixing the second fixed shaft 220 onto the top 110 of the upper frame.
[0036] In one embodiment, the first threaded groove and the second threaded groove have opposite helical directions, so the locking direction of the first nut 240 is opposite to that of the second nut 250, thereby forming a bidirectional locking mechanism. In this embodiment, the first nut 240 is first locked clockwise to a predetermined torque, and then the second nut 250 is locked counterclockwise, so that the tension end and the fixed rod 230 form a bidirectional prestressed interlock.
[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A stress loading test apparatus for extreme high and low temperature cycling tests, characterized in that, Includes a support frame, a clamping frame, and a load-bearing device; The support frame includes a frame top and a support column; there are two frame tops, and the two frame tops are respectively fixed at both ends of the support column; The clamping frame includes a specimen clamp, a fixed base, and a tension base. The fixed base is fixedly connected to the top of one of the frames. The tension base is movably installed on the top of the other frame. The distance between the tension base and the fixed base can be changed. There are two specimen clamps. One specimen clamp is fixedly installed on the tension base and the fixed base. The specimen clamp is used to clamp the end of the specimen. The load-bearing device includes a fixed end, a tensile end, and a locking assembly. The fixed end is fixedly connected to the fixed base, and the tensile end is connected to the tensile base. The tensile end passes through the top of the frame and extends outward, with the end of the tensile end extending outside the top of the frame serving as a clamping end. The fixed end can be fixed to an external tensile testing machine, and the clamping end can be subjected to load by the external tensile testing machine. The locking assembly is used to lock the clamping end onto the top of the frame.
2. The stress loading test apparatus for extreme high and low temperature cycling tests according to claim 1, characterized in that: The support column is a hollow rectangular Invar steel, and there are two support columns, which are distributed in parallel and spaced apart between the tops of the two frames.
3. The stress loading test apparatus for extreme high and low temperature cycling tests according to claim 1, characterized in that: The top of the frame is a type II double-layer Invar steel structure, the top of the frame is a hollow structure, and the top of the frame is connected to the support column by welding.
4. The stress loading test apparatus for extreme high and low temperature cycling tests according to claim 3, characterized in that: A stabilizing block is provided inside the top of the frame. The stabilizing block is made of solid Invar steel and is fixedly installed inside the middle of the top of the frame.
5. The stress loading test apparatus for extreme high and low temperature cycling tests according to claim 1, characterized in that: The specimen clamp has a clamping slot, and the end of the specimen can be inserted into the clamping slot. The specimen clamp is provided with a fixing bolt, which is used to fix the end of the specimen in the clamping slot.
6. The stress loading test apparatus for extreme high and low temperature cycling tests according to claim 1, characterized in that: A positioning pin is fixedly installed on the tension base, and the positioning pin slides through the top of the frame.
7. The stress loading test apparatus for extreme high and low temperature cycling tests according to claim 4, characterized in that: The fixed end is fixedly connected to the fixed base, the fixed end passes through the top of the frame and extends outward, and the fixed end passes through the stabilizing block. The end of the fixed end extending outside the top of the frame can be fixed on the external tensile testing machine.
8. The stress loading test apparatus for extreme high and low temperature cycling tests according to claim 1, characterized in that: The locking assembly includes two fixing rods, both of which are fixed on the tension base. The two fixing rods are distributed on both sides of the tension end. The fixing rods slide through the top of the frame. The outer side wall of the fixing rod is provided with a first threaded groove. A first nut can be screwed onto the fixing rod extending to the outside of the top of the frame.
9. The stress loading test apparatus for extreme high and low temperature cycling tests according to claim 8, characterized in that: The outer wall of the clamping end of the stretching end is provided with a second threaded groove, on which a second nut can be screwed.
10. The stress loading test apparatus for extreme high and low temperature cycling tests according to claim 9, characterized in that: The locking direction of the first nut is opposite to that of the second nut to form a bidirectional locking mechanism.