Acceleration test method for elastic supporting structure under high-temperature vibration coupling
By constructing a temperature-vibration coupling acceleration model and a multi-stress acceleration factor formula, a high-temperature vibration coupling test of an elastic support structure was realized, which solved the problems of long test time and low accuracy in the existing technology and improved the accuracy of the test results.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-04-07
AI Technical Summary
Existing technologies cannot perform high-temperature vibration coupling tests on elastic support structures, resulting in long reliability test times and poor extrapolation accuracy of test results to actual lifespan.
A temperature-vibration coupled acceleration model was constructed. Through a multi-stress acceleration model and acceleration factor formula, temperature-vibration coupled working conditions that meet the acceleration effect requirements were selected, and acceleration tests were conducted using a mechanical testing machine.
It shortened the reliability test time for elastic supports and improved the extrapolation accuracy of test results to actual life.
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Figure CN121804840A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of reliability testing technology for elastic supports, and in particular to an accelerated testing method for elastic support structures under high-temperature vibration coupling. Background Technology
[0002] The primary function of elastic supports is to reduce engine vibration and noise, ensuring engine stability and reliability. During vehicle operation, elastic supports not only bear wide-frequency, random vibration loads from the engine but are also exposed to high temperatures for extended periods. High temperatures and vibrations accelerate the aging process of the rubber materials in the elastic supports, leading to decreased stiffness, increased permanent deformation, and significantly shortened fatigue life. Therefore, accurately assessing the durability of elastic supports under high-temperature and vibration environments is of great significance for the reliability, safety, and lifespan prediction of product design.
[0003] The main failure modes of elastic supports are high-temperature failure and fatigue failure. High-temperature failure occurs when the rubber hardness decreases and its elastic modulus reduces after continuous operation in high-temperature environments, leading to reduced elasticity, lower resilience, and decreased elongation at break. This results in a decline in the performance of the elastic support, making it unable to meet the system's operational requirements. Fatigue failure occurs when, under long-term repeated stress, cracks and fissures appear on the rubber surface. During vehicle operation, engine vibration and vehicle bumps subject the elastic support to alternating stress. After stress cycles, microcracks gradually form on the rubber surface. Over time, these cracks propagate, eventually causing the elastic support to fracture.
[0004] Currently, conventional methods for testing the reliability of elastic supports are typically conducted at room temperature. This method completely ignores the softening and degradation effects of high temperatures on the properties of rubber materials, and the test results are seriously inconsistent with the actual high-temperature operating conditions of elastic supports. In addition, there is a method in the existing technology of "aging first, then testing," which involves placing the elastic support sample in a high-temperature environmental chamber for static aging for a specified time, then taking it out and cooling it to room temperature before conducting vibration fatigue testing. This method separates environmental factors from mechanical loads and cannot simulate the real "high-temperature-vibration coupling" operating conditions where high temperature and vibration act simultaneously.
[0005] None of the aforementioned existing technologies can achieve high-temperature vibration coupling tests on elastic support structures. The reliability test time for elastic supports is relatively long, and the extrapolation accuracy of the test results to the actual life is poor. Summary of the Invention
[0006] This application provides an accelerated testing method for elastic support structures under high-temperature vibration coupling, which solves the problems that existing elastic support reliability testing techniques cannot achieve high-temperature vibration coupling testing of elastic support structures, the elastic support reliability testing time is long, and the extrapolation accuracy of test results to actual life is poor.
[0007] On the one hand, this application provides an accelerated testing method for elastically supported structures under high-temperature vibration coupling, including the following steps: Step 1: Construct a temperature-vibration coupled acceleration model.
[0008] Step 2: Based on the temperature-vibration coupling acceleration model, derive the temperature-vibration coupling conditions that meet the acceleration effect requirements.
[0009] Step 3: Perform accelerated testing on the elastic support structure according to the temperature-vibration coupling conditions that meet the acceleration effect requirements.
[0010] In one possible implementation, step one includes: Based on the relationship between temperature, vibration and lifespan, an accelerated model was selected to construct a multi-stress accelerated model.
[0011] Construct the acceleration factor formula corresponding to the multi-stress acceleration model.
[0012] The multi-stress acceleration model and the corresponding acceleration factor formula together constitute the temperature-vibration coupled acceleration model.
[0013] In one possible implementation, in step one, based on the relationship between temperature, vibration, and lifetime, a multi-stress acceleration model is constructed by selecting an acceleration model, including: Based on the relationship between temperature, vibration and lifespan, a multi-stress acceleration model is constructed using the power-law model in the acceleration model, and the constants and acceleration factor power exponents in the multi-stress acceleration model are solved.
[0014] In one possible implementation, step one involves solving for the constants and acceleration factor exponents in the multi-stress acceleration model, including: Taking the logarithm of both sides of the multi-stress acceleration model yields a linearized acceleration model.
[0015] The linearized acceleration model was fitted using linear regression, and the constants and acceleration factor exponents in the multi-stress acceleration model were solved using the least squares method.
[0016] In one possible implementation, step two includes: Several sets of temperature-vibration coupled working conditions were constructed and substituted into the temperature-vibration coupled acceleration model to obtain the acceleration effect of each set of temperature-vibration coupled working conditions.
[0017] The temperature-vibration coupling conditions that meet the acceleration requirements were selected.
[0018] In one possible implementation, step three includes: The temperature-vibration coupling conditions that meet the requirements for acceleration effect are transformed into the accelerated test conditions of the mechanical testing machine.
[0019] Accelerated tests were performed on the elastic support structure using a mechanical testing machine under accelerated testing conditions.
[0020] In one possible implementation, the compressive permanent deformation rate is used as a performance indicator for the elastic support structure.
[0021] The accelerated testing method for elastically supported structures under high-temperature vibration coupling in this application has the following advantages: By constructing a temperature-vibration coupled acceleration model, the relationship between temperature-vibration coupled working conditions and acceleration effect is established. This not only shortens the reliability test time of elastic supports, but also provides a basis for high-precision extrapolation of test results to actual life. Attached Figure Description
[0022] To more clearly illustrate the technical solutions in the embodiments of this application 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 this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0023] Figure 1 This is a flowchart illustrating the accelerated testing method for high-temperature vibration coupling of an elastic support structure provided in an embodiment of this application. Detailed Implementation
[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0025] like Figure 1 As shown in the embodiments of this application, an accelerated testing method for elastically supported structures under high-temperature vibration coupling is provided, including the following steps: Step 1: Construct a temperature-vibration coupled acceleration model.
[0026] Step 2: Based on the temperature-vibration coupling acceleration model, derive the temperature-vibration coupling conditions that meet the acceleration effect requirements.
[0027] Step 3: Perform accelerated testing on the elastic support structure according to the temperature-vibration coupling conditions that meet the acceleration effect requirements.
[0028] Specifically, the elastic support structure is a rubber-metal component used in the engine compartment of a vehicle. The sensitive factors affecting its lifespan are temperature (high temperature will affect the performance of rubber materials) and vibration (elastic supports are mainly vibrated in service). Before constructing the temperature-vibration coupled acceleration model of this application, the requirements of the acceleration model are first explained: to achieve a 50% reduction in time in the experiment, that is, an acceleration factor greater than 2.
[0029] A temperature-acceleration model and a vibration-acceleration model were established in advance. Neither of these two acceleration models could achieve an acceleration factor greater than 2, thus demonstrating the effectiveness of the temperature-vibration coupled acceleration model of this application.
[0030] The process of establishing the temperature-accelerated model is as follows: A curve relating the elastic support life to the compressive permanent deformation rate was constructed to calculate the temperature-accelerated model, i.e., the Arrhenius model.
[0031] The Arrhenius model is often used to describe the relationship between temperature-accelerated stress and product life characteristics. Its formula is as follows: .
[0032] Where dM / dt is the reaction rate at temperature T (where M is the compressive permanent deformation rate and t is the lifetime). It is a constant. It is activation energy. It is the Boltzmann constant ( ), Absolute temperature (unit: ) ).
[0033] Construct Ln(dM / dt) ~ The curve, the slope of the curve is With the intercept A, the parameters of the Arrhenius model can be obtained.
[0034] Calculated =450, A=-1.947.
[0035] Thus, the final formula for the Arrhenius model is obtained: .
[0036] The acceleration factor corresponding to the final Arrhenius model is then expressed as: .
[0037] The relationship between temperature and acceleration factor is shown in Table 1: Table 1 Relationship between temperature and acceleration factor
[0038] As can be seen from Table 1, when only considering the temperature condition, the acceleration factor increases to 1.225 when the temperature increases from 25 to 80℃, which does not reach 2. Therefore, the acceleration test analysis is not conducted under the single-factor condition of temperature.
[0039] The process of establishing the vibration acceleration model is as follows: A curve relating the elastic support life to the compressive permanent deformation rate was constructed to calculate the vibration acceleration model, namely the Miner linear cumulative damage model.
[0040] The Miner linear cumulative damage model is based on the assumption that under variable amplitude fatigue loading, the damage caused by each load level can accumulate linearly, and product failure occurs when the cumulative damage reaches a certain critical value. Its basic expression is: .
[0041] in, Indicates cumulative damage. It is in the The number of cycles under different stress levels (corresponding to loads with different combinations of vibration acceleration and frequency). It is in the The fatigue life (number of cycles) of a product until failure under a stress level of 1000. The product was deemed to be faulty at that time.
[0042] Then we have: .
[0043] Where N2 represents the number of cycles, N1 represents the remaining number of cycles, a represents the amplitude, and m represents an empirical constant.
[0044] The relationship between vibration amplitude and number of cycles is as follows: The value of m can be calculated based on the number of iterations, the total number of iterations, and the amplitude. The calculated value is m = 9.67.
[0045] The relationship between lifespan and amplitude is: .
[0046] The acceleration factor corresponding to the vibration acceleration model is expressed as: .
[0047] The relationship between vibration amplitude and acceleration factor is shown in Table 2: Table 2 Relationship between vibration amplitude and acceleration factor
[0048] As can be seen from Table 2, when considering only the vibration condition, the acceleration factor increased to 1.63 when the amplitude increased from 0.0069 to 0.0944 g2 / Hz, but did not reach 2. Therefore, other conditions need to be considered and accelerated test analysis needs to be carried out.
[0049] For example, step one includes: Based on the relationship between temperature, vibration and lifespan, an accelerated model was selected to construct a multi-stress accelerated model.
[0050] Construct the acceleration factor formula corresponding to the multi-stress acceleration model.
[0051] The multi-stress acceleration model and the corresponding acceleration factor formula together constitute the temperature-vibration coupled acceleration model.
[0052] For example, in step one, based on the relationship between temperature, vibration, and lifespan, an acceleration model is selected to construct a multi-stress acceleration model, including: Based on the relationship between temperature, vibration and lifespan, a multi-stress acceleration model is constructed using the power-law model in the acceleration model, and the constants and acceleration factor power exponents in the multi-stress acceleration model are solved.
[0053] Specifically, in multi-stress accelerated testing, commonly used acceleration models include linear acceleration models, power-law models, and exponential models. For cases involving stress-life relationships such as vibration and temperature, the power-law model is a more suitable choice, as shown below: .
[0054] in, Indicates stress (Temperature) and stress Lifespan under (vibration) action, n is a constant, and n1 and n2 are the power exponents of the acceleration factor under the corresponding stress.
[0055] Let the temperature be T (unit: °C), the amplitude be R (unit: g² / Hz), and the lifetime be L (unit: h), then the multi-stress acceleration model constructed based on the power-law model is: .
[0056] For example, in step one, the constants and acceleration factor exponents in the multi-stress acceleration model are solved, including: Taking the logarithm of both sides of the multi-stress acceleration model yields a linearized acceleration model.
[0057] The linearized acceleration model was fitted using linear regression, and the constants and acceleration factor exponents in the multi-stress acceleration model were solved using the least squares method.
[0058] Specifically, in this embodiment, taking the logarithm of both sides of the multi-stress acceleration model yields the linearized acceleration model as follows: .
[0059] The linearized acceleration model was fitted using linear regression, and the constants and acceleration factor exponents in the multi-stress acceleration model were solved using the least squares method. The values of A, n1, and n2 were found to be 1.298e17, 4.9363, and 0.5584, respectively. Therefore, the multi-stress acceleration model can also be expressed as: .
[0060] The acceleration factor formula corresponding to the multi-stress acceleration model is expressed as: .
[0061] For example, step two includes: Several sets of temperature-vibration coupled working conditions were constructed and substituted into the temperature-vibration coupled acceleration model to obtain the acceleration effect of each set of temperature-vibration coupled working conditions.
[0062] The temperature-vibration coupling conditions that meet the acceleration requirements were selected.
[0063] Specifically, in this embodiment, five sets of temperature-vibration coupled operating conditions are constructed and substituted into the temperature-vibration coupled acceleration model to obtain the acceleration effect of each set of temperature-vibration coupled operating conditions, that is, the relationship between temperature-vibration coupled operating conditions and acceleration factors, as shown in Table 3: Table 3 Relationship between temperature-vibration coupling condition and acceleration factor
[0064] As can be seen from Table 3, when the temperature-vibration coupling condition is 80℃ and the vibration amplitude is 0.0944g... 2 At / Hz, the acceleration factor is 2.177, which is greater than 2, thus meeting the acceleration effect requirements.
[0065] For example, step three includes: The temperature-vibration coupling conditions that meet the requirements for acceleration effect are transformed into the accelerated test conditions of the mechanical testing machine.
[0066] Accelerated tests were performed on the elastic support structure using a mechanical testing machine under accelerated testing conditions.
[0067] Specifically, in this embodiment, an accelerated test was performed on the elastic support structure using a mechanical testing machine. The vehicle engine weighs 2.47 tons, with a total of four elastic supports, each with a counterweight of 6045N. Therefore, a load of 6045N was applied to the mechanical testing machine. The actual vehicle standard operating conditions (room temperature, 0.0069g) were used. 2 / Hz) corresponds to a stress amplitude of 1mm and a frequency f=4Hz on the mechanical testing machine; the actual vehicle acceleration condition is also (80℃, 0.0944g) 2 / Hz, which is the temperature-vibration coupling condition that meets the acceleration effect requirements, corresponds to a stress amplitude s=1mm and a frequency f=6.3Hz on the mechanical testing machine, i.e., accelerated test conditions. At this time, the acceleration factor is 2.177, and accelerated testing is performed on the elastic support structure according to the accelerated test conditions.
[0068] The specific accelerated testing process is as follows: The elastic support structure is clamped using a mechanical testing machine, and the test can begin after confirming that all components are securely installed; the preload is set to 6045N, and the pressure is increased to 6045N before the test begins; the test frequency is set to 6.3Hz, and the mechanical test control conditions are set to amplitude ±1mm, using displacement control; the mechanical testing machine is started to begin the cyclic test, and records are made; when the elastic support structure does not meet the performance indicators, the test is stopped, and the current number of cycles is recorded.
[0069] Analysis of test results: Under standard operating conditions (room temperature, 0.0069g) 2 At / Hz, the elastic support failed after 800,000 vibrations, corresponding to a vibration time of 55.56 hours; under accelerated conditions (80℃, 0.0944g), 2 At a frequency of 100000 vibrations per 10000 Hz, the corresponding vibration time is 22.04 h. The calculated actual acceleration factor is 2.52, which meets the acceleration requirements.
[0070] For example, the compression permanent deformation rate is used as a performance indicator of the elastic support structure.
[0071] Specifically, in this embodiment, the change of the compression set over time under different working conditions is calculated based on the permanent compression height. The compression set is an important indicator for measuring the elastic performance of an elastic support during long-term use. The calculation formula is as follows: .
[0072] in, Represents the compressive permanent deformation rate. The initial height of the elastic support. This refers to the residual height of the elastic support after fatigue life analysis, after the load is removed and the support has recovered for a certain period of time (e.g., 24 hours). In this embodiment, the elastic support is considered to have failed when the permanent compressive deformation rate exceeds 30%.
[0073] This application embodiment establishes the relationship between temperature-vibration coupling conditions and acceleration effect by constructing a temperature-vibration coupling acceleration model. This shortens the reliability test time of elastic supports and provides a basis for high-precision extrapolation of test results to actual life.
[0074] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.
[0075] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.
Claims
1. An accelerated testing method for elastically supported structures under high-temperature vibration coupling, characterized in that, Includes the following steps: Step 1: Construct a temperature-vibration coupled acceleration model; Step 2: Based on the temperature-vibration coupling acceleration model, derive the temperature-vibration coupling conditions that meet the acceleration effect requirements; Step 3: Perform accelerated testing on the elastic support structure according to the temperature-vibration coupling conditions that meet the acceleration effect requirements.
2. The accelerated testing method for elastically supported structures under high-temperature vibration coupling according to claim 1, characterized in that, Step one includes: Based on the relationship between temperature, vibration and lifespan, an accelerated model is selected to construct a multi-stress accelerated model; Construct the acceleration factor formula corresponding to the multi-stress acceleration model; The multi-stress acceleration model and the corresponding acceleration factor formula together constitute the temperature-vibration coupled acceleration model.
3. The accelerated testing method for elastic support structures under high-temperature vibration coupling according to claim 2, characterized in that, In step one, based on the relationship between temperature, vibration, and lifespan, a multi-stress acceleration model is constructed, including: Based on the relationship between temperature, vibration and lifespan, a multi-stress acceleration model is constructed using the power-law model in the acceleration model, and the constants and acceleration factor power exponents in the multi-stress acceleration model are solved.
4. The accelerated testing method for elastic support structures under high-temperature vibration coupling according to claim 3, characterized in that, Step one involves solving for the constants and acceleration factor exponents in the multi-stress acceleration model, including: Taking the logarithm of both sides of the multi-stress acceleration model yields a linearized acceleration model; The linearized acceleration model was fitted using linear regression, and the constants and acceleration factor exponents in the multi-stress acceleration model were solved using the least squares method.
5. The accelerated testing method for elastic support structures under high-temperature vibration coupling according to claim 1, characterized in that, Step two includes: Several sets of temperature-vibration coupled working conditions were constructed and substituted into the temperature-vibration coupled acceleration model to obtain the acceleration effect of each set of temperature-vibration coupled working conditions. The temperature-vibration coupling conditions that meet the acceleration requirements were selected.
6. The accelerated testing method for elastically supported structures under high-temperature vibration coupling according to claim 1, characterized in that, Step three includes: The temperature-vibration coupling conditions that meet the requirements for acceleration effect are transformed into the accelerated test conditions of the mechanical testing machine; Accelerated tests were performed on the elastic support structure using a mechanical testing machine under accelerated testing conditions.
7. The accelerated testing method for elastically supported structures under high-temperature vibration coupling according to claim 1, characterized in that, The compression permanent deformation rate is used as the performance index of the elastic support structure.