A modular temperature control system and sample testing method for thermal-mechanical coupling materials

Abstract

The present application relates to a kind of temperature control system and sample testing method.The temperature control system includes environmental chamber, temperature sensor assembly, temperature control unit and temperature adjustment execution unit;Environmental chamber is enclosed to form the cavity for accommodating sample and its surrounding medium;Temperature sensor assembly is used to measure the temperature in environmental chamber;Temperature control unit generates control signal according to the measured value of temperature sensor assembly;Temperature adjustment execution unit adjusts the temperature in environmental chamber according to control signal, and at least includes heat module and circulating unit.Temperature sensor assembly at least includes environmental temperature sensor, and can include at least two sample temperature sensors, and at least two sample temperature sensors measure the temperature at both ends of sample respectively;Temperature control unit represents sample temperature gradient according to the temperature difference at both ends of sample, and adjusts circulating unit power according to the temperature difference, to change the circulating speed of medium in environmental chamber;When temperature difference increases, circulating unit power is increased, and when temperature difference decreases to within preset range, circulating unit power is reduced.Sample temperature sensor can be clamped type temperature sensor, and form thermal coupling with the corresponding clamp of sample or sample end portion.The system can dynamically correct sample temperature gradient on the basis of environmental temperature closed-loop control, improve temperature uniformity, temperature stability and thermal-mechanical coupling test precision.

Description

Technical Field

[0001] This invention relates to the field of material performance testing and temperature control technology, and in particular to a testing system and method for conducting tensile loading, cyclic loading and temperature recovery tests on shape memory alloy samples under controlled temperature conditions. Background Technology

[0002] The mechanical properties of temperature-sensitive materials such as shape memory alloys are closely related to temperature. Under external loads and temperature changes, they often exhibit significant nonlinear deformation, load-unload hysteresis, and recovery characteristics with temperature changes. To obtain the performance parameters and response characteristics of such materials under different temperature and load conditions, it is usually necessary to conduct isothermal tensile cyclic tests under controlled temperature conditions and temperature recovery tests under constant load conditions after pre-deformation.

[0003] Current testing methods typically rely on materials testing equipment for load or displacement control, with temperature control often achieved through environmental chambers, liquid thermostatic baths, or dedicated temperature control systems. Among these existing technologies, dedicated temperature control systems are often highly integrated and expensive, resulting in high equipment configuration and maintenance costs. Environmental chambers or thermostatic baths, designed to meet sealing, insulation, and heat exchange requirements, have complex structures and are heavily reliant on fixtures, thermometers, and extensometers, leading to similarly high overall costs. Furthermore, existing temperature control devices, when used with materials testing equipment, suffer from limitations in switching and expanding test conditions. They struggle to achieve flexible selection of air and liquid media, isothermal cyclic tensile testing, and constant-load temperature recovery testing on a single platform with high degrees of freedom. Changing samples, arranging temperature measurement points, and adjusting clamping methods are also often constrained by space and structure, resulting in a limited adjustable range and inconvenient operation, thus reducing testing efficiency and applicability.

[0004] Therefore, existing technologies still suffer from high costs and low testing flexibility when addressing the temperature-controlled mechanical testing needs of materials such as shape memory alloys. There is an urgent need for a testing device that is compatible with devices / systems of different sizes and shapes, can be flexibly connected to different testing platforms and modularly expanded, can work collaboratively between force-thermal systems, and has strong adaptability and versatility. Summary of the Invention

[0005] To address the problems of high cost of temperature control equipment, insufficient compatibility with different material testing equipment and fixtures, easy deviation between ambient temperature and actual sample temperature, easy formation of temperature gradients between different positions of the sample, and low degree of freedom in switching test conditions for existing thermo-mechanical coupling testing of thermo-mechanical materials such as shape memory alloys, this invention provides a modular temperature control system and a sample testing method for thermo-mechanical coupling materials.

[0006] According to one aspect of the present invention, a temperature control system is provided, comprising an environmental chamber, a temperature sensor assembly, a temperature control unit, and a temperature regulation execution unit. The environmental chamber encloses a cavity for containing a sample and its surrounding medium, the medium including a gas or a liquid. The temperature sensor assembly measures the temperature within the environmental chamber. The temperature control unit is electrically connected to the temperature sensor assembly and generates a control signal based on the measured value from the temperature sensor assembly. The temperature regulation execution unit is electrically connected to the temperature control unit and regulates the temperature within the environmental chamber according to the control signal. The temperature regulation execution unit includes at least a thermal module and a circulation unit, and the temperature control unit adjusts the operating state of the thermal module and / or the circulation unit based on the measured value from the temperature sensor assembly.

[0007] In some embodiments, the temperature sensor assembly includes an ambient temperature sensor and a first sample temperature sensor. The ambient temperature sensor is disposed inside the ambient chamber and in contact with the ambient medium to measure the ambient temperature; the first sample temperature sensor is disposed on the sample, or at a location thermally coupled to the sample, to measure the sample temperature. Thus, the temperature control system can acquire not only the temperature of the ambient medium but also the actual temperature of the sample, thereby avoiding testing errors caused by inferring the sample temperature solely from the ambient temperature.

[0008] In some embodiments, the first sample temperature sensor is a clamp-on sample temperature sensor. The clamp-on sample temperature sensor includes a clamp body, a jaw, and a temperature measuring point. The jaw forms an opening and closing space for accommodating and clamping the sample. The clamp body provides clamping force to ensure the jaw fits against the outer surface of the sample. The temperature measuring point is located inside the jaw. With this structure, the sample temperature sensor can be quickly clamped onto the sample or a corresponding clamp at the sample end, forming direct contact or thermal coupling with the sample, thereby improving the ease of installation, contact stability, and reliability of sample temperature measurement.

[0009] In some implementations, the temperature control unit adjusts the power of the thermal module based on the difference between the measured value from the temperature sensor assembly and the target temperature. Further, the temperature control unit can adjust the power of the thermal module based on the difference between the measured value from the ambient temperature sensor and the target temperature, and correct the power of the thermal module based on the difference between the measured value from the first sample temperature sensor and the measured value from the ambient temperature sensor. Thus, the temperature control system can be based on closed-loop control of the ambient temperature, combined with compensatory control using the actual sample temperature, enabling the sample to approach the target temperature more quickly and reducing the following hysteresis between the ambient temperature and the actual sample temperature.

[0010] In some embodiments, the temperature sensor assembly further includes a second sample temperature sensor. The first and second sample temperature sensors are used to measure the temperature at different locations on the sample, respectively. The temperature control unit controls the circulation power of the circulation unit based on the temperature difference between the first and second sample temperature sensors. Specifically, when the temperature difference between different locations on the sample increases, the temperature control unit increases the circulation power of the circulation unit to increase the circulation speed of the medium in the ambient chamber and enhance convective heat transfer or medium mixing; when the temperature difference decreases to a preset range, the temperature control unit reduces the circulation power of the circulation unit to reduce unnecessary disturbances and maintain a stable temperature field. Thus, the temperature control system can dynamically correct the circulation intensity of the medium in the ambient chamber according to the sample temperature gradient, improving the sample temperature uniformity and the reliability of the thermo-mechanical coupling test results.

[0011] In some implementations, the temperature sensor assembly and the temperature control unit are separate components. The temperature sensor assembly can be located within a confined space inside the sample, fixture, or environmental chamber, while the temperature control unit can be located outside the environmental chamber or away from high-temperature areas and moving parts. This allows the system to flexibly arrange the temperature measurement positions under different material testing equipment, different fixture types, and different sample sizes, and improves the convenience of disassembly, maintenance, and module expansion.

[0012] In some embodiments, the temperature control system further includes a temperature display device. The temperature display device is located outside the environmental chamber and connected to the temperature sensor assembly, used to display the temperature measurements acquired by the temperature sensor assembly. Further, when the temperature sensor assembly includes an environmental temperature sensor and / or a sample temperature sensor, the temperature display device can display the ambient temperature, the sample temperature, and / or the temperature difference between different locations on the sample, so that the user can determine whether the environmental temperature establishment process, the isothermal maintenance state, the actual sample temperature, and the sample temperature gradient meet the testing requirements.

[0013] In some implementations, the thermal module is used to heat and / or cool the ambient medium, and / or to directly heat the sample. The thermal module may only regulate the temperature of the ambient medium, or it may act directly on the sample, or it may include both an ambient thermal module for regulating the ambient temperature and a sample thermal module for directly regulating the sample temperature. Thus, the temperature control system can select between ambient medium temperature control, direct sample temperature control, or a combination of both, depending on different testing conditions, improving the system's adaptability to different testing conditions such as isothermal tensile testing, cyclic loading, and constant-load temperature recovery.

[0014] In some embodiments, the clamp and / or jaw of the clamp-on sample temperature sensor can form an electrically conductive clamping element. This electrically conductive clamping element is electrically connected to the thermal module and is used to form a conductive connection with the sample to input current into the sample. Thus, the clamp-on sample temperature sensor can simultaneously perform sample clamping, temperature measurement, and electrical connection functions, reducing the number of additional components, simplifying the sample end structure, and improving system integration.

[0015] In some embodiments, the environmental chamber is a gas environment chamber. The gas environment chamber forms a gas cavity surrounding the sample testing area to contain the gaseous medium. A heating module is used to heat the gaseous medium, and a circulation unit includes a fan that drives the gaseous medium to circulate between the gas cavity and the heating module, thereby delivering the heated gaseous medium to the gas cavity and forming a continuous circulating airflow. By driving the gaseous medium circulation with a fan, localized heat buildup and localized cold zones can be reduced, improving the uniformity of temperature distribution in the gas environment.

[0016] In some embodiments, the environmental chamber is a water bath environmental chamber. The water bath environmental chamber forms a liquid cavity around the sample testing area to contain the liquid medium. A thermal module is used to heat the liquid medium, and a circulation unit includes a water pump to drive the liquid medium to circulate within the liquid cavity. The water bath environmental chamber may also include circulation channels, flow guiding structures, and / or filtration structures to optimize the flow field distribution of the liquid medium and improve circulation stability. Direct heat exchange between the liquid medium and the sample can improve heat exchange efficiency, shorten temperature settling time, and reduce temperature differences between different locations on the sample.

[0017] In some implementations, the environmental chamber can be a flexible environmental chamber. The flexible environmental chamber is detachably installed in the loading space of the materials testing equipment and forms a controlled temperature environment around the sample testing area. The flexible environmental chamber adapts to different sizes of testing equipment, fixtures, tie rods, sensor arrangements, and sample testing areas through a flexible shell, flexible fitting area, constriction structure, opening and closing structure, and / or sealing structure. Thus, the environmental chamber can be quickly installed and disassembled without changing the main structure of the materials testing equipment, improving the versatility, adaptability, and modular expansion capabilities of the temperature control system.

[0018] According to another aspect of the present invention, a sample testing method based on the above-described temperature control system is provided, comprising: installing an environmental chamber in the loading space of a material testing device and enclosing the sample testing area; acquiring temperature measurements within the environmental chamber using a temperature sensor assembly; generating a control signal by a temperature control unit based on the temperature measurements; adjusting the operating state of a thermal module and / or a circulation unit by a temperature regulation execution unit based on the control signal to regulate the temperature within the environmental chamber and / or the sample; and applying a mechanical testing force to the sample after the temperature within the environmental chamber reaches a set state.

[0019] In some embodiments, the sample testing method further includes: acquiring the ambient temperature using an environmental temperature sensor, acquiring the sample temperature using at least one sample temperature sensor, and adjusting the power of the thermal module based on the difference between the ambient temperature and the target temperature; in the case of two sample temperature sensors, acquiring the temperature at different locations on the sample using the two sensors respectively, and adjusting the circulation power of the circulation unit based on the temperature difference between the two locations. Thus, this method can simultaneously control the ambient temperature, monitor the actual sample temperature, and correct the sample temperature gradient during thermo-mechanical coupling testing, enabling the acquisition of load, displacement / strain, and temperature data under more stable and uniform temperature field conditions.

[0020] Compared with the prior art, the present invention has at least the following beneficial effects:

[0021] First, the temperature control system of the present invention forms a closed-loop temperature control structure through a temperature sensor assembly, a temperature control unit, and a temperature adjustment execution unit. The temperature control unit can adjust the working state of the heat module and / or the circulation unit in real time according to the measured value of the temperature sensor assembly, so that the ambient indoor temperature converges to the target temperature and remains stable, thereby improving the temperature control accuracy and temperature control stability.

[0022] Secondly, the temperature control system of this invention simultaneously acquires both the ambient temperature and the sample temperature. The temperature control unit, based on closed-loop control of the ambient temperature, adjusts the power of the thermal module in conjunction with the actual sample temperature. Therefore, the system can reduce the deviation between the ambient temperature and the actual sample temperature, minimizing temperature judgment errors caused by relying solely on ambient temperature for control, and enabling the sample to reach the target temperature state more quickly and accurately.

[0023] Third, the temperature control system of this invention can acquire the temperature at different locations on the sample using at least two sample temperature sensors, and characterize the sample temperature gradient based on the temperature difference between these locations. The temperature control unit adjusts the circulation power of the circulation unit according to this temperature difference, dynamically adjusting the flow rate or circulation intensity of the medium within the ambient chamber as the temperature gradient changes. Simultaneously, the power adjustment of the thermal module compensates for the deviation between the ambient temperature and the target temperature, while the power adjustment of the circulation unit mitigates uneven temperature distribution within the ambient chamber and the sample temperature gradient. Therefore, the system can simultaneously ensure both temperature stability and temperature uniformity, improving the reliability of temperature boundary conditions in thermo-mechanically coupled material testing.

[0024] Fourth, the clamp-on sample temperature sensor of the present invention can be clamped onto the sample or a corresponding fixture at the end of the sample, and forms direct contact or thermal coupling with the sample through the temperature measuring point inside the clamp. This structure facilitates the rapid arrangement of sample temperature measuring points within the loading space of the material testing equipment, improving the convenience of temperature measuring point installation, contact stability, and repeatability, thereby enhancing the reliability of sample temperature data.

[0025] Fifth, the temperature control system of this invention can adapt to different media conditions, such as gas environment chambers and water bath environment chambers. In a gas environment chamber, the circulation unit can drive the gas medium circulation through a fan; in a water bath environment chamber, the circulation unit can drive the liquid medium circulation through a water pump. Therefore, the system can select appropriate heat modules and circulation unit configurations for different heat exchange media, improving the adaptability of the temperature control system to different test temperature field requirements. Attached Figure Description

[0026] The accompanying drawings are used to further illustrate the technical solutions of the present invention and constitute a part of this specification. The schematic drawings and their descriptions are for explaining the present invention only and do not constitute an undue limitation on the scope of protection of the present invention. Wherein:

[0027] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the overall structure of the environmental chamber in one embodiment of the present invention;

[0029] Figure 3 This is a cross-sectional view of the environmental chamber in one embodiment of the present invention;

[0030] Figure 4 This is a schematic diagram of the structure of the flexible shell forming a longitudinally expanding and contracting space in one embodiment of the present invention;

[0031] Figure 5 This is a schematic diagram of a flexible shell multilayer composite structure in one embodiment of the present invention;

[0032] Figure 6 This is a schematic diagram of a perforated tape structure in one embodiment of the present invention;

[0033] Figure 7 This is a schematic diagram of a double-layered closing structure in one embodiment of the present invention;

[0034] Figure 8 This is a schematic diagram of the structure of a socket-type flexible environmental chamber in one embodiment of the present invention;

[0035] Figure 9 This is a schematic diagram of the structure of a cover sheet provided at the opening and closing interface in one embodiment of the present invention;

[0036] Figure 10 This is a system block diagram of a temperature control system according to an embodiment of the present invention;

[0037] Figure 11 This is a schematic diagram of the structure of the clamping sample temperature sensor clamping the sample in one embodiment of the present invention. Detailed Implementation

[0038] Several embodiments of the present invention will now be described with reference to the accompanying drawings. Where the shape, relative position, and other aspects of the components described in the embodiments are not explicitly defined, the scope of the invention is not limited to the components shown in the drawings. The components shown in the drawings are for illustrative purposes only. Furthermore, while many details have been set forth, it should be understood that some embodiments of the invention may be practiced without these details. In other instances, structures and techniques well-known in the art have not been shown in detail so as not to obscure the understanding of the invention.

[0039] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. Spatially related terms, such as “below,” “under,” “down,” “above,” “above,” etc., may be used herein for convenience in describing the relationship of one element or feature to one or more other elements or features, as illustrated in the accompanying drawings. It should be understood that spatially relative terms are intended to cover different orientations of the device during use or operation other than those shown in the accompanying drawings. For example, if the device in the drawings is flipped, an element described as “below” or “under” other elements or features may then be oriented “above” other elements or features. Thus, the exemplary term “below” can cover both the orientations above and below. The device may be oriented in other ways (e.g., rotated 90 degrees or otherwise), and the spatially relative descriptive terms used herein are interpreted accordingly.

[0040] As used herein, the singular forms “a,” “the,” etc., are intended to include the plural forms as well, unless the context otherwise indicates. It should be further understood that the terms “comprising” and / or “including” define the presence of a feature, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or collections thereof.

[0041] The terms “or” and “and / or” as used herein should be interpreted as inclusive or refer to any one or any combination thereof. Therefore, “A, B, or C” or “A, B, and / or C” means “any one of the following: A; B; C; A and B; A and C; B and C; A, B, and C.” Exceptions to this definition only arise when the combination of elements, functions, steps, or behaviors is inherently mutually exclusive to some extent.

[0042] The term "connection" as used in this article encompasses various connection methods, including direct and indirect connections, without requiring physical contact between the connected parts. Specific connection methods include snap-fit ​​connections, screw connections, connections without fixing devices, welding, riveting, and integral molding. In the context of component mating, it includes various mating relationships such as clearance fits, transition fits, interference fits, or variable clearance.

[0043] This invention relates to a testing system for temperature-controlled mechanical testing, suitable for use in conjunction with material testing equipment to test the mechanical response of temperature-sensitive materials under different temperature conditions. The testing system includes an environmental chamber 100 and a temperature control system 200. In some embodiments, the environmental chamber can be used in conjunction with testing equipment for applying test conditions to the sample. The testing equipment can be a material testing device, a mechanical loading device, a thermo-mechanical coupling testing device, or other equipment capable of applying loads, displacements, strains, cyclic loads, constant loads, temperature paths, or other test parameters to the sample. The specific structural form of the testing equipment is not limited, as long as it can apply mechanical force and / or preset test parameters to the sample during the test, and together with the environmental chamber, form the sample testing conditions. The environmental chamber 100 is used to create a controlled temperature environment around the sample, and the temperature control system 200 is used to regulate and stabilize the temperature within the environmental chamber. After the environmental chamber is set in the working area of ​​the material testing equipment and arranged around the sample, it can realize isothermal tensile cyclic testing, pre-deformation and constant load temperature recovery testing, and other working conditions without changing the main structure of the testing equipment, thereby reducing the configuration cost of a dedicated temperature-controlled testing system and increasing the freedom of working condition configuration.

[0044] As an optional embodiment, the environmental chamber is a flexible environmental chamber. The flexible environmental chamber is detachably installed in the working space between the two columns of the testing equipment or near the fixtures, and encloses a temperature-controlled cavity. The temperature-controlled cavity covers the sample gauge length and its adjacent area, and can be spatially adapted to the fixture structure and the installation position of the temperature measuring elements. To improve the problem of existing environmental chambers being highly dependent on fixture size, tie rod position, and sensor arrangement, resulting in a small adaptation range and insufficient testing freedom, the flexible environmental chamber adopts a flexible shell structure. The flexible shell can undergo elastic or recoverable deformation within a certain range, allowing the environmental chamber to still achieve enclosure and coverage when changing different specifications of fixtures, different testing equipment models, or different measuring devices, thereby improving compatibility and adaptation freedom.

[0045] like Figure 2As shown, the flexible environmental chamber 110 may include a shell body 111 forming the outer surface of the chamber, and at least one flexible adaptation area 112. The shell body 111 forms the main environmental area, and the flexible adaptation area 112 adapts to the frame of the test device, forming a seal with the frame. The flexible adaptation area 112 may be located at the opening and closing edge of the shell body, the transition area adjacent to the fixture, or near the protrusion position of the test device's pull rod, so as to make way or fit the fixture shape, pull rod diameter changes, extensometer clamping arm or optical measurement field of view requirements in the installed state. After the flexible shell is assembled into the working area of ​​the test device, its shape contour can be changed by pressing, stretching, springing or partial folding, so that the environmental chamber maintains continuous coverage with the outside world, while avoiding rigid restrictions on the size and installation position of the fixture. Therefore, when the size of the test device changes or the fixture model needs to be changed, there is no need to re-process a matching rigid environmental box or replace the entire environmental chamber. It can be quickly adapted by the deformation of the flexible shell, thereby improving the system's compatibility with different test configurations and the freedom of field use.

[0046] In one embodiment, the flexible environmental chamber 120 is as follows: Figure 3 As shown, the flexible outer shell 121 is a horizontally extendable structure. For example, the flexible outer shell adopts a horizontally pleated structure. The pleated structure has several folds / pleats arranged circumferentially or laterally along the environmental chamber, forming multiple fan-shaped segments between the folds. In the closed state, each fan-shaped segment moves closer together and encloses the chamber to form a temperature-controlled cavity. In the unfolded state, it unfolds around the folds to increase the lateral coverage of the cavity. As an optional implementation, the folds corresponding to the pleated structure can be flat folds or butterfly folds, etc., and the present invention does not limit this.

[0047] The horizontal extension of the flexible shell 121 refers to the deformability of the flexible shell, which is mainly reflected in the change of the cross-sectional dimensions of the cavity, including but not limited to changes in the cavity's coverage radius, coverage perimeter, coverage angle, or lateral width. By adjusting the unfolding angle of each blade segment, the flexible shell can achieve lateral expansion when the clamp is replaced, the clamp size is increased, or the cable layout needs to make way; and it can achieve lateral contraction when the clamp size is small or heat leakage needs to be reduced, thus balancing adaptability and sealing.

[0048] In this embodiment, the folds / pleats can extend along the axial direction of the flexible shell, so that the flexible shell remains essentially unchanged or changes little in the height direction, while the size adjustment is mainly achieved through lateral expansion / contraction. A flexible adaptation area 122 can be provided at the opening and closing edge of the flexible shell. The flexible adaptation area 122 changes its adaptation size with the amount of lateral expansion to maintain a sealed enclosure under different lateral dimensions. Optionally, the flexible adaptation area 122 is made of an elastic material and does not have pleats, thereby ensuring a sealing effect. As an optional implementation, for a single pleat, a shaping strip or reinforcing rib can be provided along the fold line position of the single pleat to improve the pleat strength, giving the flexible shell a more precise expansion trajectory and improving repeatability accuracy, so that the flexible shell can maintain its preset shape after multiple expansions / contractions.

[0049] In another embodiment, such as Figure 4 As shown, the flexible shell 131 is a vertically extendable structure with a corrugated telescopic shape. The corrugated telescopic shape forms continuous folds / corrugations along the axial direction (corresponding to the sample length direction) or height direction of the environmental chamber, allowing the flexible shell 131 to be stretched or compressed in the vertical direction, thereby changing the effective length or height of the temperature control chamber.

[0050] The vertical extension of the corrugated stretchable flexible shell refers to the deformation of the flexible shell, primarily manifested in changes in the axial dimensions of the cavity, including but not limited to changes in cavity height, effective coverage length, or the distance between the upper and lower ports. When the sample gauge position changes, the distance between the upper and lower clamps changes, or a temporary increase in operating space is required during sample loading, the flexible shell can be stretched vertically to extend the coverage area; when it is necessary to reduce the volume of ineffective cavities, improve temperature control efficiency, or reduce heat loss, the flexible shell can be compressed vertically to shorten the coverage area. This vertically stretchable corrugated stretchable structure is particularly suitable for applications requiring testing of the elastic response curve of the sample, in which the sample needs to be stretched in the extension direction (…). Figure 4 The test device applies a deformation force (vertical direction) to the sample, meaning it may move vertically up and down in the vertical direction. During the movement of the test device, the flexible shell can change its height while ensuring a tight seal within the chamber.

[0051] In this embodiment, the fold direction of the corrugated section is aligned with the axial direction of the environmental chamber, allowing the flexible shell to have a significant expansion and contraction stroke in the vertical direction, while remaining essentially constant or exhibiting minimal variation in the horizontal direction (direction of the cavity cross-section). This avoids interference with the fixture or unstable sealing due to lateral dimensional fluctuations. The upper and lower ends of the flexible shell can respectively form upper and lower ports. The upper and lower ports can be fitted to the adjacent areas of the fixture through elastic closures, tightening bands, or overlapping sealing structures, thereby maintaining the sealing continuity at the ports while expanding and contracting in the vertical direction.

[0052] If necessary, limiting bands or limiting ribs can be set in the corrugated section. For example, for a flexible shell with axial expansion and contraction, a limiting line can be set between the upper and lower flexible adaptation areas to limit the maximum height of the flexible shell with axial expansion and contraction; for a flexible shell with lateral contraction, the maximum circumference of the flexible shell with contraction can be limited in the horizontal direction to limit the maximum stretching length and avoid excessive stretching that could cause material fatigue; as an optional implementation, a rebound support including springs and elastic bands can also be set so that the flexible shell can automatically retract to a preset length after the external force is released, thereby improving assembly efficiency and repeatability.

[0053] In some embodiments, such as Figure 5 As shown, the flexible shell adopts a multi-layer composite structure to meet the requirements of heat insulation, temperature resistance, and durability. The outer side of the flexible shell can be a wear-resistant and tear-resistant layer to withstand the friction generated by frequent loading and unloading and contact with the edges of the clamps.

[0054] by Figure 3 In a corresponding embodiment, the flexible shell has a material layer on its outer surface 111a that meets the requirements for gas tightness and / or liquid tightness. The outer surface material forms a continuous and dense barrier interface to reduce the risk of gas and liquid infiltration. The outer surface material has a gas tightness function, which is used to block the exchange between the air inside the chamber and the outside air, preventing the formation of convection between the inside and outside air and introducing additional heat exchange channels, thereby reducing heat disturbance and improving the temperature field stability of the chamber. As an optional implementation, the outer surface material also has a liquid tightness function, which is used to prevent liquid water from seeping into the chamber through the shell; when the temperature inside the chamber is low, condensation may occur on the outer surface of the shell. The liquid tightness barrier can prevent condensation from entering the chamber and causing humidity changes, condensation pollution, or affecting temperature measurement and temperature control. By using a material with both gas tightness and liquid tightness on the outer surface, dual suppression of gas convection disturbance and condensation infiltration is achieved, improving the environmental isolation capability and operational reliability of the gas environment chamber under different temperature conditions.

[0055] The material of the outer surface 111a can be a high-barrier polymer film, a dense layer of rubber elastomer, or a multi-layer composite structure to form a continuous and dense sealing interface while maintaining flexibility and deformability. The outer surface material can be selected from thermoplastic polyurethane film, polyamide film, ethylene-vinyl alcohol copolymer barrier layer, polyvinylidene chloride coated film, polyvinylidene fluoride film, polytetrafluoroethylene dense film, silicone rubber dense layer, butyl rubber film, fluororubber film, ethylene propylene rubber film, or nitrile rubber film to suppress air convection and moisture penetration. The outer surface material can also adopt a multi-layer composite structure, such as a co-extruded composite film of polyamide / ethylene-vinyl alcohol copolymer / polyethylene, a composite film of polyester / polyurethane, a composite structure of fluoropolymer film and elastomer substrate, or a laminated structure with an airtight coating and a waterproof coating on the substrate surface, to balance flexibility, resistance to low-temperature condensation environments, and long-term sealing stability. The outer surface material can also be selected according to the usage environment, with a formulation system that has higher resistance to hydrolysis, chemical corrosion and temperature cycling, and can be formed into an integral sealing layer through hot pressing, coating curing or co-extrusion molding to improve the reliability of gas seal and liquid seal.

[0056] The intermediate layer 111b can be a thermal insulation layer to reduce heat exchange between the ambient chamber and the outside environment and improve temperature control efficiency. The thermal insulation layer can be selected from high and low temperature resistant elastomers, flexible polymer films, coated fabrics or composite materials according to the target temperature range. The material thickness and number of layers can be adjusted according to the cavity size, temperature uniformity requirements and assembly space constraints.

[0057] In some embodiments, the inner layer of the flexible shell is a sheet or membrane structure. The materials of the inner layer include, but are not limited to, one or more of polytetrafluoroethylene (PTFE) membrane, expanded polytetrafluoroethylene (ePTFE) membrane, polyimide film, polyetheretherketone (PEEK) film, silicone rubber sheet, fluororubber sheet, or fluorosilicone rubber sheet. By selecting heat-resistant polymer membranes or rubber sheets, the inner layer can maintain flexibility under high temperature, low temperature, and alternating thermal conditions, and reduce the risk of cracking, powdering, or significant hardening.

[0058] In some embodiments, the inner layer is a composite membrane structure, such as... Figure 5 As shown, the composite membrane structure includes a polymer base membrane 111c and a metallization layer 111c' disposed on the polymer base membrane. The metallization layer can be a vapor-deposited metal layer or a metal foil layer, and the metal material can be aluminum or an aluminum alloy, etc. By setting the metallization layer, the water vapor barrier performance and / or gas barrier performance of the inner layer are improved. At the same time, the metallization layer reflects the radiant heat in the temperature control cavity, thereby reducing heat loss and improving temperature control efficiency.

[0059] In some embodiments, the inner layer is a coating structure. The inner layer is formed by coating material applied to the surface of a substrate, which may be a fabric base or a fiber layer; the coating material includes, but is not limited to, one or more of silicone rubber coating, fluoropolymer coating, polyurethane coating, or temperature-resistant modified resin coating. By forming a continuous and dense coating on the substrate surface, the inner layer achieves lower permeability and better resistance to condensate erosion, and is easy to clean and maintain.

[0060] In some embodiments, the thickness of the inner layer is 0.02 mm to 1.0 mm, for example, 0.05 mm to 0.5 mm. By limiting the thickness range of the inner layer, the inner layer can ensure airtightness / liquid tightness and abrasion resistance while still meeting the flexibility required for folding, unfolding, or stretching deformation of the flexible shell.

[0061] In some embodiments, the inner layer surface is a low surface energy surface or a hydrophobic surface to reduce condensation adhesion and improve drainage; and / or the inner layer is treated with antifouling to reduce the impact of oil, dust or frost residue on the sensor and sample inside the temperature control cavity; and / or the inner layer is treated with antistatic treatment to reduce the risk of contamination caused by electrostatic adsorption of particles.

[0062] In some embodiments, the inner layer is connected to other layers of the flexible outer shell by one or more of the following methods: heat sealing, hot-press bonding, adhesive bonding, sewing bonding, or mechanical compression. Optionally, when sewing the connection, a sealing tape, heat-sealing strip, or a sealing material is applied to the seam area to reduce pinhole leakage and maintain seal continuity.

[0063] As an optional implementation, such as Figure 3 As shown, the flexible adaptation area 122 of the flexible environmental chamber 120 is elastic. The flexible adaptation area 122 is used to reduce the diameter of the opening end and lock it after the flexible shell covers the target device, tooling, or test area, thereby reducing gas exchange and moisture ingress / exit between the temperature control chamber and the outside environment, reducing cold or heat leakage, and maintaining the positioning stability of the flexible shell under thermal cycling, vibration, or repeated assembly / disassembly conditions. Optionally, the flexible adaptation area 122 can also be used to provide a controlled exit path for sensor leads, temperature signal transmission lines, or power supply lines to reduce the risk of wear, compression, and pull-out of the wiring harness at the opening edge.

[0064] In some embodiments, such as Figure 6As shown, the flexible adaptation area employs a perforated tape structure 124'. The perforated tape structure 124' is located in the circumferential region of the open end, forming a perforated channel 127 along the circumferential direction. This perforated channel can be formed by a flanged covering structure, an edge-binding tape structure, or a reinforcing webbing structure. Multiple perforations are spaced circumferentially along the perforated channel. Reinforcing sheets, reinforcing layers, or high-strength fiber rings can be placed around the perforations to improve tear resistance. The tape is alternately threaded between the multiple perforations. The tape can be a drawstring, flat tape, or high-strength fiber rope. A buckle, cord lock, or self-locking clip can be installed at the end of the tape to achieve rapid tightening and loosening. By tightening the tape, the open end contracts circumferentially, creating a circumferential clamping force on the target area, enabling the flexible shell to obtain adjustable clamping and positioning capabilities at the open end. The perforated end cap structure is easy to adapt to target parts with different outer diameter ranges, has high installation and disassembly efficiency, and the perforated channel can provide a path for the wire harness to be led out; in some embodiments, at least one perforation is configured as the exit hole for the temperature signal transmission line, and a protective coil, wear-resistant bushing or elastic compression ring is provided around the perforation to reduce the friction between the wire harness and the hole wall and reduce gap leakage.

[0065] In some embodiments, such as Figure 3 , 4 As shown, the flexible adaptation area employs a built-in sealing strip structure 124 and 134. The built-in sealing strip enters through a first perforation at the upper or lower end of the environmental chamber and exits through a second perforation on the opposite side, forming a channel between the first and second perforations to accommodate and guide the sealing strip as it inserts and slides. Alternatively, the built-in strip channel can be formed by folding the inner layer of the flexible shell inwards, or by connecting an independent strip to the flexible shell; the connection method includes heat sealing, heat-pressing composite, adhesive composite, or sewing connection and integral molding, and sealing tape or sealing material can be applied to the seam area to reduce the risk of leakage.

[0066] The sealing tape can be a drawstring, flat tape, or high-strength fiber rope. The ends of the sealing tape can be equipped with buckles, cord locks, or self-locking clips for quick tightening and loosening. Tightening the sealing tape causes the open end to contract circumferentially, creating a circumferential tightening force on the target area. For internal sealing tapes, since the insertion section of the sealing tape is located in the belt channel inside the housing, there is no need to provide discrete perforations around the housing, thereby reducing potential leakage channels caused by openings and improving overall sealing continuity and durability.

[0067] In some embodiments, such as Figure 7As shown, the flexible adaptation area adopts a double-layer sealing structure combining an internal sealing strip 144a and an external perforated sealing strip 144b. The internal sealing strip 144a is positioned closer to the main body of the environmental chamber at the opening end of the flexible shell, and it passes through an internal threading channel (strip track) that extends continuously along the circumference of the opening end. When the internal sealing strip is tightened, the opening end forms a continuous circumferential contact pressure on the covered part, thereby forming a primary sealing interface that is preferentially used for airtight / liquid-tight sealing. The external perforated sealing strip 144b is positioned further away from the main body of the environmental chamber at the opening end. The external sealing strip alternately passes through and tightens through multiple perforations along the circumference of the shell to apply circumferential clamping and locking to the opening end. This ensures that the flexible shell remains stable under conditions of material creep / rebound caused by vibration, tension, assembly / disassembly, and temperature cycling, thus serving as a primary means of mechanical fixation, anti-slip, and stress relief. When the inner and outer sealing strips are used together, the inner sealing strip is tightened first to establish a seal, and then the outer perforated sealing strip is tightened to complete the positioning and locking. The tightening force of the outer perforated sealing strip is used to maintain the fit with the inner sealing strip and reduce the disturbance of the sealing interface by external pulling.

[0068] In some embodiments, such as Figure 8 As shown, the flexible environmental chamber 150 and the testing device are fitted together using a sleeve connection. In this configuration, the flexible outer shell 151 has no opening or closing structure, forming a single unit. The flexible outer shell 151 is configured in both circumferential and axial dimensions to fit entirely into and cover the testing device. During assembly, the flexible outer shell is axially sleeved onto the testing device from one end to a predetermined position, ensuring a continuous or controlled-gap fit between the outer circumferential surface of the flexible shell and the outer circumferential surface of the testing device for at least a certain axial length. After the sleeve connection is completed, the open end of the flexible shell is reduced in diameter through a flexible fitting area and pressed against the outer circumferential surface, end step, or transition rounded corner area of ​​the testing device, achieving a tight fixation of the open end. Because the sleeve connection method does not introduce additional splicing connectors or through-type opening and closing interfaces between the flexible shell and the testing device, the flexible shell material remains intact and continuous in the circumferential direction, reducing leakage paths and thus achieving higher sealing reliability and temperature field stability.

[0069] In some embodiments, such as Figure 3 , 4 As shown in Figures 6 and 7, the flexible environment chamber adopts a surround-opening and closing mechanism. The flexible shell forms an openable and closable interface along its circumference. During assembly, the flexible shell unfolds around the testing device in the open state and covers it to a predetermined position. Then, the openable and closable interface is closed through the opening and closing structure, transforming the flexible shell from an unfolded state to an enclosed state. For example... Figure 3As shown, the opening and closing structure of the flexible shell may include a zipper structure 125, and optionally one or more of the following: hook and loop fasteners, Velcro, snap fasteners, snap buttons, or roll fasteners. The wraparound opening and closing method allows for encapsulation assembly without needing to be slipped onto the end of the testing device. It is suitable for scenarios where the end of the testing device has protruding parts, abrupt changes in shape, or is inconvenient to axially slip onto. Furthermore, by adjusting the closing position or allowing for overlap allowance, it can adapt to testing devices with different outer diameters, heights, or external contours, thereby improving versatility and field adaptability.

[0070] In some embodiments, such as Figure 9 As shown, the closable interface surrounding the opening mechanism is a potential leakage path. Even after closing, the closable interface may still form micro-gaps or through-gap extending along its length. To reduce this leakage risk, the closable interface is structurally configured with overlapping shielding and multi-level barrier features. Overlapping edges are provided on both sides of the closable interface, forming an overlapping cover after closing. As an optional implementation, the zipper structure uses a waterproof zipper, a film-coated zipper, or a zipper structure with a sealing lip. A pressure strip or cover plate 166 can be provided on the outside of the zipper. The cover plate 166 connects with the flexible shell to form a covering channel to reduce leakage at the zipper teeth. For Velcro or snap fastener structures, after closing, the closable interface can be subjected to additional load through external straps or circumferential clamping straps to keep the overlapping area continuously compressed, thereby reducing slack gaps caused by material springback, creep, or temperature cycling.

[0071] In some embodiments, the opening portion of the flexible housing is provided with an additional sealing structure, such as... Figure 3 123 in Figure 4 In section 133, the additional sealing structure is used to form a compressible elastic sealing interface between the flexible shell and the covered part to compensate for the micro gaps generated at the open end due to assembly tolerances, irregular shape, surface roughness differences, and material rebound changes caused by thermal cycling. This reduces gas exchange and water vapor intrusion, reduces cold or heat leakage, and improves the sealing effect and temperature stability of the temperature control cavity in the open end area.

[0072] In some embodiments, such as Figure 3As shown, the additional sealing structure is a foam seal 123. The foam seal 123 is continuously arranged circumferentially along the open end, forming an annular sealing ring or a segmented circumferential sealing ring. The foam seal 123 is disposed on the inner mating surface of the open end, the inner surface of the flange of the open end, or the pressing area adjacent to the flexible adaptation area of ​​the open end. This ensures that after the open end is tightened, the foam seal 123 is radially compressed and forms a surface contact or multi-point contact seal with the outer surface of the covered part. The material of the foam seal 123 can be closed-cell foam, microporous elastic foam, foamed rubber, or foamed silicone to reduce gas permeation and improve resilience. The surface of the foam seal 123 can be provided with a coating layer, a coating layer, or a film layer to improve resistance to condensation, oil stains, and wear.

[0073] In some embodiments, such as Figure 3 As shown, the additional sealing structure 123 works in conjunction with the flexible adaptation area 122. The flexible adaptation area 122 applies a tightening force in the circumferential direction and provides primary positioning. Under the action of the tightening force, the sealing structure 123 undergoes elastic compression and fills the micro-gap, forming a secondary sealing barrier. When there are wire harness protrusions, local protrusions, or areas with changes in outer diameter at the opening end, the compressibility of the sealing structure 123 can provide differentiated contact pressures at different locations, thereby suppressing the formation of local leakage points. In some embodiments, the sealing structure 123 is configured as a replaceable structure, with a disassembly and assembly interface or positioning reference reserved at the opening end, facilitating quick replacement after foam aging, permanent compression deformation, or contamination, to maintain long-term sealing performance.

[0074] With its flexible shell structure, the flexible environmental chamber can adapt to test devices of different sizes and increase the degree of freedom of adaptation. It reduces the dependence of the environmental chamber on specific test equipment and fixture models, and provides greater structural layout space and operating condition expansion capability for the system integration of temperature control system and environmental chamber.

[0075] The temperature control system 200 is used to regulate and stabilize the ambient temperature in the environmental chamber. It is also used to measure, process and determine the sample temperature and the ambient temperature, and generate a control strategy based on this to drive the temperature regulation execution unit, thereby realizing closed-loop temperature control with the ambient temperature as the main regulation object and the sample temperature as the key constraint / correction quantity.

[0076] The temperature control system 200 includes a temperature sensor assembly 201, a temperature control unit 202, and a temperature regulation execution unit 203. The temperature sensor assembly 201 acquires the sample temperature and ambient temperature, and inputs the temperature signal to the temperature control unit 202 to form a closed-loop control. The temperature sensor assembly 201 includes an ambient temperature sensor 2011, a first sample temperature sensor 2012, and a second sample temperature sensor 2013. The first sample temperature sensor 2012 and the second sample temperature sensor 2013 measure the temperature of the sample, while the ambient temperature sensor 2011 measures the temperature of the ambient medium inside the ambient chamber, which includes at least one of a gas or a liquid medium.

[0077] In some embodiments, such as Figure 11 As shown, the sample temperature sensor 2012 adopts a clamping structure. The clamping structure includes a clamp body 20121, a clamping opening 20122, and a temperature measuring point 20123. The clamping opening 20122 forms an opening and closing space for accommodating and clamping the sample. The clamp body 20121 provides clamping force to make the clamping opening fit against the outer surface of the sample 300. The temperature measuring point 20123 is arranged inside the clamping opening, so that when the clamping structure is clamped on the sample, the temperature measuring point 20123 forms direct contact with the sample 300 or forms thermal coupling through a heat-conducting medium, thereby collecting the real-time temperature of the sample.

[0078] The clamp can be an elastic clamp, spring clamp, or screw clamp structure. The inner surface of the clamp 20122 can be provided with a flexible thermally conductive layer, a heat-resistant insulating layer, or an anti-slip layer to reduce thermal resistance and suppress clamp slippage while ensuring electrical isolation and clamping stability. The temperature measuring point 20123 can be any one or more of thermistors, thermocouples, and thin-film resistance thermometers. A stress relief structure and an insulating encapsulation structure can be provided between the temperature measuring point and the lead wire to reduce lead wire fatigue and measuring point offset caused by tensile loads, vibration, or temperature cycling.

[0079] Optionally, the sample temperature sensor can be configured as a single-point or multi-point temperature measurement structure. In a multi-point temperature measurement structure, multiple temperature measurement points simultaneously measure the temperature near a certain location on the sample, thereby improving the temperature measurement accuracy.

[0080] Optionally, a thermistor can be used as the sample temperature sensor. Thermistors are small in size and simple in structure, ensuring full contact with the sample. Furthermore, in the range from room temperature to tens or hundreds of degrees Celsius, thermistors typically have a large resistance-temperature slope (high sensitivity), making it easier to obtain finer temperature resolution with simpler acquisition circuitry.

[0081] In some embodiments, the environmental temperature sensor 2011 is disposed inside the environmental chamber and in contact with the environmental medium to measure the ambient temperature and serve as feedback for the temperature control system. The environmental temperature sensor 2011 can be located in the main airflow channel, return channel, mixing zone near the heating element, fan outlet side, or sample vicinity of the environmental chamber to characterize the representative temperature within the chamber and reduce the impact of local temperature differences on control accuracy. The environmental temperature sensor can be one or more of a thermistor, thermocouple, or thin-film resistance thermometer. A waterproof, anti-condensation, or corrosion-resistant protective layer can be provided on the outer surface of the sensor to adapt to working conditions in gaseous or liquid environments. The environmental temperature sensor can be disposed inside the environmental chamber by bracket fixing, wall mounting, or through-wall sealed installation. When installed through a wall, a sealing structure can be provided at the wall penetration location to reduce environmental medium leakage and improve temperature control stability.

[0082] As an optional implementation, a second sample temperature sensor 2013 is further added, forming a "2+1" temperature measurement configuration consisting of an ambient temperature sensor 2011, a first sample temperature sensor 2012, and a second sample temperature sensor 2013. The first sample temperature sensor 2012 and the second sample temperature sensor 2013 are respectively located in the corresponding clamps at both ends of the sample, forming a stable thermal coupling with the sample and used to characterize the temperature state at both ends of the sample; the ambient temperature sensor 2011 is still used for ambient temperature acquisition and temperature control feedback, and the second sample temperature sensor 2013 is used to cooperate with the first sample temperature sensor 2012 to output the temperature difference between the two ends of the sample and thereby characterize the axial temperature gradient of the sample.

[0083] By adding a second sample temperature sensor 2013, compared to the scheme that only configures the ambient temperature sensor 2011 and the first sample temperature sensor 2012, it is possible to simultaneously obtain the temperature data at both ends of the sample without changing the original closed-loop control loop. The temperature difference between the two ends can be directly calculated and recorded as a temperature uniformity index, thus providing verifiable data for the sample temperature consistency in isothermal mechanical tests. When the ambient temperature remains stable but the temperature difference between the two ends continues to deviate from the preset range, it can identify the temperature gradient caused by asymmetrical heat dissipation at the ends of the sample or uneven local temperature field, and provide criteria for test waiting, data rejection, or device adjustment.

[0084] This method is particularly suitable for testing shape memory alloys. The phase transformation initiation and termination temperature ranges of shape memory alloys are temperature-sensitive. If there is a temperature deviation between the two ends of the sample during the test, the two ends may be in different phase states or different phase transformation processes at the same time, resulting in inconsistencies between the phase transformation plateau, phase transformation stress level, and recovery strain at the ends. The end temperature difference obtained by two sample temperature sensors can be used to determine whether the phase transformation process is approximately synchronous across the entire length of the sample, thereby improving the reliability of phase transformation-related feature point identification.

[0085] In some embodiments, the temperature control system further includes a temperature display device. The temperature display device is located outside the environmental chamber and is connected to the environmental temperature sensor and / or sample temperature sensor via wired and / or wireless means, for selectively displaying the environmental temperature and / or sample temperature. By placing the temperature display device outside the environmental chamber, the user can obtain the temperature status inside the chamber without opening it, thereby facilitating the assessment of the environmental temperature establishment process, the isothermal maintenance status, and whether the actual sample temperature meets the testing requirements.

[0086] As an optional implementation, the temperature display device is also used to display the temperature difference between different locations on the sample to indicate the sample temperature gradient to the user. By displaying the absolute value of the sample temperature and / or the sample temperature difference, a basis can be provided for starting the test, extending the holding time, adjusting the cycle intensity, or correcting the test data.

[0087] like Figure 10 As shown, the temperature regulation execution unit 203 is used to regulate and maintain the internal temperature of the environmental chamber to form a stable temperature field that meets the requirements of thermo-mechanical coupling tests. The temperature regulation execution unit 203 includes a thermal module 2031 and a circulation unit 2032. The thermal module 2031 is used to heat / cool the environmental medium to form a heat medium for temperature regulation; the circulation unit 2032 is used to provide circulation driving force, transporting the heated environmental medium to the environmental chamber and forming a continuously flowing circulating medium to balance the temperature inside the chamber.

[0088] In some embodiments, the heating module 2031, in addition to heating and / or cooling the ambient medium, can also directly act on the sample to regulate its temperature. The heating module 2031, acting directly on the sample, can shorten the time it takes for the sample temperature to reach the target value and reduce the hysteresis of the sample temperature relative to the ambient temperature. The heating module 2031 can be used only for ambient temperature regulation, or only for direct sample heating, or it can simultaneously include an ambient heating module for regulating the ambient temperature and a sample heating module for directly regulating the sample temperature.

[0089] In some embodiments, the thermal module 2031, which acts directly on the sample, employs an electric heating method. The electric heating method generates Joule heat in the sample by applying current, thereby achieving direct temperature regulation. Alternatively, the clamp and / or jaws of the clamp-type sample temperature sensor can form an electrically conductive clamping element, which is electrically connected to the thermal module 2031 acting directly on the sample to input current to the sample. Thus, the clamp-type sample temperature sensor structurally performs sample clamping, temperature measurement, and electrical connection functions simultaneously, thereby reducing the number of additional components, simplifying the sample end structure, and improving system integration.

[0090] Taking the circulation unit 2032 as an example of a fan, during the fan's operation, the output airflow completes heat exchange near the thermal module and carries heat into the environmental chamber. The hot air diffuses and flows back along a predetermined flow path within the chamber, achieving agitation and renewal of the air within the chamber space. This weakens localized heat accumulation and the formation of localized cold zones, reduces the temperature gradient within the chamber, and improves the uniformity of temperature distribution. Compared to static heating, maintaining airflow through the circulation unit 2032 ensures more thorough heat transfer within the chamber, faster temperature response, and better spatial consistency after temperature stabilization. This is beneficial for providing a relatively balanced thermal environment for the sample and clamping area at the set target temperature and provides a stable execution basis for subsequent closed-loop temperature control.

[0091] The temperature regulation execution unit 203 establishes closed-loop control logic based on the detection results of the temperature sensor component 201. It regulates the ambient temperature within the environmental chamber using the target temperature as the setpoint and dynamically corrects the temperature uniformity within the chamber. During control, it acquires the real-time measurement values ​​of the target temperature and the ambient temperature sensor 2011, calculates the temperature deviation, and modulates the output power of the thermal module 2031 based on the temperature deviation. Simultaneously, it controls the coordinated output of the thermal module 2031 and the circulation unit 2032 to ensure the ambient temperature converges towards the target temperature and remains stable. By using the measurement value of the ambient temperature sensor 2011 as feedback for closed-loop power regulation, the accuracy of ambient temperature control can be improved, and temperature fluctuations can be reduced.

[0092] As an optional implementation, the adjustment of the thermal module's output power is also based on the temperature difference between the ambient temperature sensor and the sample temperature sensor. If the difference between the ambient temperature and the sample temperature is large, the power of the thermal module can be increased, thereby quickly adjusting the sample temperature and improving the temperature control efficiency of the temperature control system. Optionally, in terms of the adjustment sequence, the power of the thermal module is first adjusted based on the difference between the ambient temperature and the target temperature, which is a process of bringing the sample close to or reaching the target temperature. After the sample approaches or reaches the target temperature, control is then performed based on the temperature difference between the ambient temperature and the sample temperature. At this point, taking the heating process as an example, the ambient temperature can be allowed to be higher than the target temperature, thereby quickly modulating the sample temperature and improving the temperature control efficiency.

[0093] Optionally, the temperature regulation execution unit 203 further utilizes the temperature difference between multiple temperature sensors as a metric for evaluating temperature uniformity. When there is a difference between the measured values ​​of the first sample temperature sensor 2012, the second sample temperature sensor 2013, or all three temperature sensors, the temperature difference is calculated, and the power or circulation efficiency of the circulation unit 2032 is adjusted according to the magnitude of the temperature difference to change the medium flow rate and circulation intensity within the chamber. The power of the circulation unit 2032 increases with the increase of the temperature difference, thereby increasing the flow rate of the medium and enhancing convective heat transfer and mixing of hot and cold media, thus accelerating the diffusion and redistribution of heat within the chamber, reducing the temperature gradient, and making the temperature distribution within the chamber more uniform. When the temperature difference decreases to a preset range, the power of the circulation unit 2032 is reduced to minimize unnecessary disturbances and maintain a stable temperature field.

[0094] During real-time control, the thermal module power adjustment is used to compensate for the deviation between the ambient temperature and the target temperature, while the circulation unit power adjustment is used to suppress gradient errors caused by uneven internal temperature. These two adjustments can be performed independently or in conjunction. When heat loss occurs due to insufficient sealing performance in the ambient chamber, the thermal module output is dynamically increased by continuously monitoring the ambient temperature deviation to compensate for the heat loss in a timely manner, ensuring the chamber temperature remains near the target temperature. Simultaneously, increasing the airflow circulation intensity improves local heat exchange conditions, reducing local temperature differences caused by leaks, external disturbances, or structural heat sinks. Through real-time closed-loop control of temperature, heating power, and rotation speed, synchronous adjustment of temperature stability and uniformity is achieved, enhancing the reliability of temperature control under non-ideal sealing conditions.

[0095] A temperature signal transmission line connects the temperature sensor assembly 201 and the temperature control unit 202, and is used to stably transmit the temperature signal collected by the temperature sensor assembly 201 to the temperature control unit 202 for temperature display, recording, and control calculations. One end of the temperature signal transmission line is electrically connected to each temperature sensor in the temperature sensor assembly 201, and the other end is electrically connected to the temperature input interface of the temperature control unit 202, enabling reliable wiring between different installation locations and reducing the impact of external electromagnetic interference on the temperature measurement signal.

[0096] The temperature sensor assembly 201 and the temperature control unit 202 are configured separately via a temperature signal transmission line. The temperature sensor can adopt a smaller structure and be placed near the fixture, sample, or other space-constrained locations, thereby improving installation freedom and layout flexibility. The temperature control unit 202 can be centrally located away from high-temperature areas, moving parts, or confined spaces, facilitating operation, maintenance, and replacement. As a component of the modular temperature control system, the temperature signal transmission line supports rapid connection and disconnection of the temperature sensor, enabling rapid combination and expansion of the temperature sensor assembly 201 and the temperature control system 200 under different experimental conditions.

[0097] Optionally, the temperature signal of any module in the temperature sensor assembly 201 can be transmitted wirelessly.

[0098] As an alternative implementation, the environmental chamber is a water bath environmental chamber, and the temperature control system 200 is a water bath temperature control system. The water bath environmental chamber is used to create a constant temperature liquid environment covering the sample testing area; the water bath environmental chamber forms a water medium circulation space inside, and the water medium directly exchanges heat with the outer surface of the sample. Compared with the gas medium, a higher heat transfer coefficient can be obtained, thereby reducing the temperature settling time and reducing the axial temperature difference of the sample.

[0099] The water bath environment chamber includes a heater and a water pump. The heater provides heat to the water medium to raise or maintain the water bath temperature; the water pump drives the water medium to circulate within the water bath environment chamber, homogenizing the temperature field of the water medium, enhancing convective heat transfer, and reducing local hot spots and temperature stratification. The water bath environment chamber may also include circulation channels, flow guiding structures, or filtration structures to optimize the flow field distribution and improve circulation stability; an insulation layer can be installed on the outside of the water bath environment chamber to reduce heat conduction and convective heat loss between it and the outside environment, improve temperature stability, and reduce energy consumption.

[0100] In this embodiment, the temperature control system 200 is electrically connected to the thermal module 2031 and the circulation unit 2032, and is also signal-connected to the environmental temperature sensor 2011, the first sample temperature sensor 2012, and the second sample temperature sensor 2013. The temperature control system 200 collects the water bath ambient temperature and sample temperature through the temperature sensor assembly 201, and adjusts the output power of the thermal module 2031 based on the deviation between the set temperature and the measured value of the environmental temperature sensor 2011 to achieve closed-loop control of the water bath temperature. The circulation unit 2032 can be implemented by a water pump under liquid conditions. The water pump operates continuously or intermittently according to a control strategy to maintain water medium circulation and temperature uniformity. Since there is heat loss due to heat conduction and convection between the water bath environment chamber and the outside environment, the temperature control system 200 dynamically adjusts the heating input to match the heating power with the heat loss in a time-averaged sense, thereby stabilizing the water bath ambient temperature within the set range and ensuring that the sample is in a stable and controllable constant-temperature liquid environment during the test period.

[0101] The sample testing method based on the temperature control system of this invention integrates the temperature control system of this invention with an environmental chamber to achieve controllable circumferential and axial temperature boundaries, verifiable temperature field, and synchronous acquisition and traceability of thermo-mechanical data. The method includes the following steps:

[0102] Environmental chamber preparation: Install the environmental chamber in the loading space of the material testing equipment and make it enclose the sample gauge length. The outer side of the environmental chamber is equipped with a thermal insulation structure to reduce undesirable heat exchange with the outside environment and the frame of the testing equipment. Select a gas environment chamber or a liquid environment chamber according to the test target and complete the modular assembly so that the sample is in a relatively closed heat exchange space, thereby providing stable boundary conditions for subsequent temperature control and mechanical loading.

[0103] Temperature control system connection: Connect the temperature control unit 202 to the temperature regulation execution unit 203, the environmental chamber, and the data acquisition system, and enable the temperature control unit 202 to drive the temperature regulation execution unit 203 to input heat to the medium inside the chamber; connect the circulation unit 2032 to the environmental chamber and complete the connection of the fan convection loop under gas conditions or the pump circulation loop under liquid conditions; connect the temperature signal transmission line to the temperature control unit 202, the temperature sensor assembly 201, and the data acquisition system respectively, and complete the channel verification to ensure that temperature setting, execution, and recording are in the same control and acquisition system.

[0104] Temperature measurement point arrangement: An environmental temperature sensor 2011 is arranged in the environmental chamber and serves as the feedback quantity for the closed-loop control of the temperature control system 200. A first sample temperature sensor 2012 and a second sample temperature sensor 2013 are arranged at both ends of the sample or on both sides of the gauge length and connected to the data acquisition system to achieve synchronous recording with load, displacement / strain. The sample temperature measurement is used to verify the actual temperature and temperature difference of the sample and to provide a basis for judging the uniformity of the temperature field, thereby avoiding the accumulation of errors caused by inferring the material state based solely on the ambient temperature.

[0105] Stable ambient temperature: The temperature control system 200 is activated and the target temperature or preset temperature path is set. The thermal module 2031 adjusts its output under the feedback of the ambient temperature sensor 2011 and converges the ambient chamber temperature to the set value. At the same time, the circulation unit 2032 is activated to form forced convection or circulation flow in the chamber to reduce temperature stratification. The stability of the temperature field is determined by the range of ambient temperature fluctuation, the range of temperature difference between two measurement points of the sample, and the steady-state holding time. When the temperature difference or fluctuation exceeds the preset range, the speed / flow rate of the circulation unit 2032 is increased or the holding time is extended to bring it back within the range.

[0106] Mechanical test force application: Under the condition that the temperature control system maintains constant temperature or operates according to the preset temperature path, the material testing equipment applies mechanical test force conditions according to displacement control, strain control or load control. The mechanical path includes loading-unloading cycle, loading to a specified strain and holding, constant load holding, etc. During the entire mechanical loading process, the cyclic unit is kept running continuously and the ambient temperature is kept stable in a closed loop, so that the sample undergoes phase transformation and deformation response in a relatively uniform temperature field, which facilitates the acquisition of repeatable stress-strain-temperature coupled data.

[0107] Temperature path execution: Under the condition of keeping the mechanical boundary unchanged or changing according to preset rules, the temperature control system 200 performs heating, cooling or segmented heating and cooling and heat preservation on the environmental chamber; the feedback of the environmental temperature sensor 2011 is used to correct the output of the thermal module 2031 in real time and reduce overshoot; the circulation unit 2032 is used to improve the heat exchange capacity and shorten the time constant of sample temperature following; the first sample temperature sensor 2012 and the second sample temperature sensor 2013 are used to synchronously record and monitor the temperature difference and thermal hysteresis, so that the phase change platform, hysteresis curve and recovery process can accurately correspond to the temperature path.

[0108] Synchronous data acquisition: The measured values ​​of load, displacement / strain, and ambient temperature sensor 2011, as well as the measured values ​​of the first sample temperature sensor 2012 and the second sample temperature sensor 2013, are synchronously acquired and stored under a unified sampling clock. The temperature setpoint, actual value, heating and cooling rate and deviation are recorded along with the mechanical data and time-aligned, so that the post-processing can correlate the material response with temperature fluctuation, temperature difference and rate deviation, and improve the consistency of parameter identification and working condition comparison.

[0109] Results Extraction and Archiving: Based on the synchronously acquired data, the phase transition start / end characteristic points, plateau stress / strain, hysteresis area, residual strain, recovery strain, and temperature-sensitive parameters are extracted. The parameter results are then bound and archived with the environmental temperature fluctuations, sample temperature differences, temperature path deviations, and cycle unit operating status recorded during the test, providing traceable data for material model calibration and engineering applications.

[0110] This invention is not limited to the specific structure and arrangement shown. Any technical solution that adopts a similar technical solution and can achieve a similar effect should be considered to fall within the protection scope of this invention.

Claims

1. A temperature control system, characterized in that: The temperature control system includes an environmental chamber, a temperature sensor assembly, a temperature control unit, and a temperature regulation execution unit; The environmental chamber is enclosed to form a cavity for containing the sample and its surrounding medium, which may include gas or liquid. The temperature sensor assembly is used to measure the temperature inside the ambient room. The temperature control unit is electrically connected to the temperature sensor assembly and is used to generate a control signal based on the measured value of the temperature sensor assembly. The temperature regulation execution unit is electrically connected to the temperature control unit and is used to adjust the temperature of the ambient room according to the control signal. The temperature regulation execution unit includes at least a thermal module and a circulation unit, and the temperature control unit adjusts the working state of the thermal module and / or the circulation unit according to the measured value of the temperature sensor assembly.

2. The temperature control system according to claim 1, characterized in that, The temperature sensor assembly includes an ambient temperature sensor and a first sample temperature sensor. The ambient temperature sensor is arranged inside the ambient chamber and in contact with the medium inside the ambient chamber, and is used to measure the ambient temperature. The first sample temperature sensor is arranged on the sample or at a position that forms thermal coupling with the sample, and is used to measure the sample temperature.

3. The temperature control system according to claim 2, characterized in that, The first sample temperature sensor is a clamp-type sample temperature sensor, which includes a clamp body, a clamp opening, and a temperature measuring point. The clamp opening forms an opening and closing space for accommodating and clamping the sample. The clamp body provides clamping force to make the clamp opening fit against the outer surface of the sample. The temperature measuring point is arranged inside the clamp opening.

4. The temperature control system according to any one of claims 1 to 3, characterized in that, The temperature control unit adjusts the power of the thermal module based on the difference between the measured value of the temperature sensor assembly and the target temperature.

5. The temperature control system according to claim 4, characterized in that, The temperature sensor assembly includes an ambient temperature sensor and a first sample temperature sensor. The temperature control unit first adjusts the power of the thermal module based on the difference between the measured value of the ambient temperature sensor and the target temperature, and then corrects the power of the thermal module based on the difference between the measured value of the first sample temperature sensor and the measured value of the ambient temperature sensor.

6. The temperature control system according to claim 2 or 3, characterized in that, The temperature sensor assembly further includes a second sample temperature sensor. The first sample temperature sensor and the second sample temperature sensor are used to measure the temperature at different locations of the sample, respectively. The temperature control unit controls the circulation power of the circulation unit based on the temperature difference between the first sample temperature sensor and the second sample temperature sensor.

7. The temperature control system according to claim 2, characterized in that, The temperature sensor assembly and the temperature control unit are separate components.

8. The temperature control system according to any one of claims 1 to 7, characterized in that, It also includes a temperature display device, which is located outside the environmental chamber and connected to the temperature sensor assembly, for displaying the temperature measurement value acquired by the temperature sensor assembly.

9. The temperature control system according to any one of claims 1 to 7, characterized in that, The thermal module is used to heat and / or cool the indoor medium, and / or to directly heat the sample.

10. The temperature control system according to claim 3, characterized in that, The thermal module is used to directly heat the sample. The clamp body and / or clamp opening of the clamp-type sample temperature sensor form an electrically conductive clamping component. The electrically conductive clamping component is electrically connected to the thermal module and is used to form a conductive connection with the sample to input current to the sample.

11. The temperature control system according to claim 6, characterized in that, The environmental chamber is a gas environment chamber, which forms a gas cavity around the sample testing area to contain the gas medium. The heating module is used to heat the gas medium. The circulation unit includes a fan, which drives the gas medium to circulate between the gas cavity and the heating module, so as to deliver the heated gas medium to the gas cavity and form a continuous circulating airflow.

12. The temperature control system according to claim 6, characterized in that, The environmental chamber is a water bath environmental chamber, which forms a liquid chamber around the sample testing area to contain the liquid medium. The thermal module is used to heat the liquid medium. The circulation unit includes a water pump, which is used to drive the liquid medium to circulate within the liquid chamber.

13. The temperature control system according to claim 12, characterized in that, The water bath environment chamber also includes a circulation channel, a flow guiding structure, and / or a filtration structure.

14. A sample testing method based on the temperature control system according to any one of claims 1 to 13, characterized in that, include: The environmental chamber is installed in the loading space of the material testing equipment and encloses the sample testing area. The temperature measurement value of the indoor environment is obtained through the temperature sensor assembly; The temperature control unit generates a control signal based on the measured temperature value; The temperature regulation execution unit adjusts the working state of the thermal module and / or the circulation unit according to the control signal to regulate the temperature of the ambient room and / or the sample. After the temperature in the ambient room reaches the set state, a mechanical testing force is applied to the sample.

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