A tire tread rubber friction heat stability evaluation and early warning method and system based on multi-temperature high slip retention rate

Abstract

This invention relates to the field of tire rubber compound performance evaluation technology, and more particularly to a method and system for evaluating and warning of the frictional thermal stability of tire tread rubber based on high slip retention rate at multiple temperatures. At a reference temperature T... ref With high temperature T high The friction coefficient as a function of slip ratio μs curve is obtained, the curve is smoothed or interpolated, and low slip and high slip intervals are defined. The retention rate R in the high slip interval is calculated. area And further calculate the temperature decay coefficient D area The method combines repeatability criteria to output representative values. Furthermore, it introduces the wear amplification factor Aw obtained from slip wear testing to establish a calibration relationship, determine thresholds, and output green, yellow, and red light graded early warnings. This method can sensitively identify the risk of high-temperature, high-slip frictional attenuation, supporting formulation screening, mass production change assessment, and abnormal wear attribution.

Description

Technical Field

[0001] This invention relates to the field of tire rubber compound performance evaluation technology, and in particular to a method and system for evaluating and warning of the frictional thermal stability of tire tread rubber based on high slip retention rate at multiple temperatures. Background Technology

[0002] With the increase in overall vehicle weight and peak torque of new energy vehicles (EVs), and the frequent start-and-brake cycles in urban congestion, tire tread compounds are more prone to high-slip events and temperature accumulation in actual use. For example, rapid acceleration, emergency braking, slippage on low-traction surfaces, and continuous cornering can cause significant shear and frictional heat generation at the tire-road contact interface, leading to increased tread surface temperature, changes in viscoelastic response, and softening or sticking of the resin / tackifying system. This often manifests as good tread friction performance in low or medium slip zones, but a significant decrease in the coefficient of friction under high slip and high temperature conditions, resulting in reduced braking or traction capacity and further amplifying the risk of slip wear and tear, causing reduced mileage, abnormal wear, or localized flaking. Therefore, the development of tread compound formulations for high-performance tires and EV tires requires an evaluation method that can rapidly, sensitively, and engineerably identify the risk of high-temperature + high-slip friction decay under laboratory conditions, providing quantitative basis for formulation screening, mass production change assessment, and abnormal wear attribution.

[0003] In existing technologies, descriptions of the frictional characteristics between tires and road surfaces typically introduce curves showing the coefficient of friction as a function of slip (i.e., μ-slip curves or μ-slip curves), and consider the influence of factors such as temperature, sliding speed, and contact pressure on frictional behavior. For example, Chinese patent (CN101057129A) discloses a method for calculating tire friction slip curves. It calculates effective μ-slip values ​​under different slip values ​​and forms μ-slip curves based on factors such as the sliding speed between tire tread blocks and rough surfaces, and tire temperature (including temperature rise caused by friction), thereby predicting vehicle braking behavior and handling characteristics. This paper emphasizes the coupling relationship between the coefficient of friction and multiple characteristic values ​​such as temperature and speed, and points out that a more realistic μ-slip curve can be obtained by considering instantaneous temperature changes. However, this approach focuses primarily on how to establish or calculate the μ-slip curve, aiming to more realistically reproduce the tire's frictional response on the road. The typical output is still the curve itself or macroscopic indicators related to braking / handling. In the tread compound formulation development stage, engineers often need a more lightweight criterion: one that can directly answer whether a particular formulation carries a risk of frictional collapse under high temperature and high slip conditions. Relying solely on curve comparisons often presents two problems: First, differences in baseline friction levels in the low-slip zone of different formulations can mask the true attenuation trend in the high-slip zone, leading to misjudgments when interpreting the curves. Second, the shape of the curves is significantly affected by factors such as equipment, road surface medium, load, and speed, lacking unified and transferable quantitative indicators and implementable graded safeguards, making it difficult to support internal formulation access control, release standards, or risk warning rules within the company.

[0004] In addition, another category of existing technologies revolves around tire testing and data collection. For example, Chinese patent (CN103221799B) discloses a diagnostic tire testing method involving stopping distance testing, traction testing, and data collection. In the traction test, friction coefficient-slip (or Fx-slip) data can be obtained and a friction coefficient-slip curve can be generated. This curve can be compared under different inflation pressures to evaluate tire performance standards. This type of approach is relatively complete in terms of testing dimensions, data collection methods, and test organization, emphasizing the acquisition of tire performance data through multi-condition testing. However, this document still focuses on performance diagnosis at the whole tire or tire-vehicle system level. It does not provide a specific quantitative index system for material screening regarding the decay mechanism of tread rubber materials' friction retention capacity under high temperature and high slip conditions, nor does it establish a thermal stability early warning framework linked to wear amplification or tear risk. In other words, even if friction coefficient-slip curve data is obtained, there is still a lack of a clear and unified solution on how to extract an index from the curve that is sensitive to friction decay under high temperature and high slip conditions and can form a threshold guard within the enterprise.

[0005] In recent years, some rapid characterization methods for tread rubber grip performance have emerged. For example, Chinese patent (CN115326431A) proposes to decompose the grip contribution into modulus contribution and friction retention coefficient, and uses DMA and other methods to quickly obtain the dry grip capability of the tread rubber through data processing, which has a good correlation with the actual dry braking distance of the tire. The advantage of this type of method is that it can bypass complex road tests or whole tire tests and achieve rapid evaluation through laboratory instruments; however, its evaluation object and operating condition focus are more on dry grip capability and the establishment of its correlation with braking distance, which may not fully cover the high slip + high temperature accumulation scenarios common in new energy vehicles. For formulations containing a high proportion of grip resin or using a low softening point resin system, thermal softening, interfacial tackiness and viscoelastic response changes at high temperatures may mainly be reflected in the abnormal decay of the friction coefficient in the high slip zone, and this decay is often highly coupled with failure modes such as wear amplification and tearing. If only a single temperature or single slip point / single feature evaluation method is used, it may still be difficult to identify the critical risk of collapse in the high slip zone in time. As a result, the formulation may perform normally in bench or short-cycle tests, but expose abnormal wear and durability problems under actual high temperature and high slip conditions.

[0006] In summary, while existing technologies can establish and acquire μ-slip curves, conduct tire traction / braking tests under multiple conditions and collect friction-slip data, and quickly characterize certain grip performance characteristics and establish correlations with overall vehicle braking indicators, they still have shortcomings in meeting the specific needs of tread compound formulation development and risk management. Specifically, there is a lack of a thermal stability evaluation method that considers multiple temperatures, focuses on friction retention in the high-slip zone, and can output engineerable graded early warning results. In particular, for high-resin formulations that require both low-slip grip and high-slip anti-fading capabilities, traditional curve comparisons or single-temperature evaluations are insufficient to establish a unified quantitative threshold. Furthermore, the lack of a stable and repeatable indicator system makes formulation selection reliant on experience, mass production change assessments lack auditable basis, and abnormal wear attribution is difficult to quickly pinpoint high-slip decay caused by thermal softening / stickiness. Therefore, it is necessary to propose an evaluation method that can extract high-slip retention characteristics at at least two temperatures and further achieve risk-graded early warning through cross-temperature decay quantification to meet the formulation development and quality management needs of new energy vehicle tires and high-performance tire tread compounds in high-temperature, high-slip scenarios. Summary of the Invention

[0007] The technical objective of this invention is to provide a quantitative evaluation and graded early warning method for high slip retention capability based on the friction coefficient-slip ratio curve of tread rubber under multiple temperature conditions, by using a reference temperature... With high temperature The friction retention characteristics of the low-slip and high-slip ranges are extracted to construct the high-slip retention rate and its temperature decay index. Combined with repeatability criteria and wear amplification calibration, the risk of friction decay, wear amplification and tearing of high resin or heat-sensitive formulations under high temperature + high slip conditions can be quickly identified and engineered for control. This supports the screening of tread compound formulations for new energy vehicles and high-performance tires, evaluation of mass production changes and attribution of abnormal wear.

[0008] Firstly, in order to achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0009] A method for evaluating and providing early warning of the tribothermal stability of tire tread rubber based on high slip retention rate at multiple temperatures, comprising the following steps:

[0010] S1, Curve Acquisition: On a friction testing device, the same tread rubber sample is subjected to friction tests at at least two temperatures, including a reference temperature. With high temperature And satisfy At each temperature Under the same normal load Same relative motion characterization quantity And under the same road surface medium conditions, sampling step size based on slip ratio. For slip ratio By performing a sweeping motion, discrete curves showing the variation of the friction coefficient with the slip ratio are obtained. ;

[0011] S2, Curve Preprocessing and Interval Determination: For the discrete curves... Smoothing and / or interpolation are performed to obtain the continuous friction function. And determine the low slip range. With high slip range Among them, satisfying ;

[0012] S3, Range retention rate calculation: For each temperature Calculate the retention rate of the high slip zone The formula for its calculation is:

[0013] ;

[0014] in, S4, Temperature Attenuation Coefficient and Repeatability Criterion: Calculate the temperature attenuation coefficient. The formula for its calculation is:

[0015] ;

[0016] And repeat the test on the same formula. This time received Calculate its coefficient of variation ;when At that time, The output is a representative value of the repeated test;

[0017] S5, Calibration-based graded early warning output: Obtains the high-temperature wear amplification factor of the same formulation in the slip wear test. and based on and After determining the warning threshold based on the calibration relationship, the frictional thermal stability level or risk warning result is output, and the risk warning includes at least green light, yellow light and red light levels.

[0018] Preferably, in step S1, the for For any value or any subinterval of, the for any value or any subinterval of.

[0019] Preferably, in step S2, the smoothing process includes any one of Savitzky-Golay smoothing, moving average smoothing, or low-pass filtering; the interpolation process includes any one of spline interpolation or polynomial interpolation.

[0020] And / or, the low slip range satisfies and The high slip range satisfies and ;

[0021] Preferably, in step S2, the low slip range is The high slip range is .

[0022] Preferably, in step S3, the slip ratio sweep range is: And the sampling step size for[ any value or any subinterval of ].

[0023] Preferably, in step S4, the number of repeated tests... The upper limit of the allowed coefficient of variation for any value or any sub-interval of, and the representative value for The mean or median.

[0024] Preferably, the high-temperature wear amplification factor Calculate using the following formula:

[0025] ;

[0026] in, For temperature The slip ratio in the wear test is as follows: Wear amount over time The slip ratio is the slip ratio in the wear test; the slip wear test is the Lambourn test or a modified Lambourn test.

[0027] Preferably, the calibration relationship is as follows: As the independent variable, with The dependent variable is determined by a monotonic regression relationship or threshold mapping relationship, and the yellow light threshold is determined accordingly. With red light threshold And satisfy ;when Output green light, when Output yellow light, when Output red light.

[0028] Secondly, the present invention also provides a tire tread rubber friction thermal stability evaluation and early warning system for implementing the method, comprising: a data acquisition module, a curve preprocessing module, an interval setting module, an index calculation module, a repeatability determination module, and an early warning output module; wherein, the data acquisition module is used for... and Collect discrete curves The curve preprocessing module is used to output the continuous friction function. The interval setting module is used to determine... and The indicator calculation module is used to calculate... , and The repeatability determination module is used for... , and Output representative value The early warning output module is used for output based on threshold parameters. , Output green / yellow / red levels.

[0029] Thirdly, the present invention also provides a computer-readable storage medium having a computer program or instructions stored thereon, which, when executed by a processor, implement the steps of the method.

[0030] Fourthly, the present invention also provides a computer program product, including a computer program or instructions that, when executed by a processor, implement the steps of the method.

[0031] This invention utilizes at least two temperatures ( and The same tread rubber sample was obtained under the following conditions. The curve is smoothed / interpolated in the low-slip range. With high slip range Calculate the integral area ratio retention rate Further construct the temperature decay coefficient This effectively eliminates the interference of low-slip baseline differences in judgment, significantly improving the sensitivity to overall frictional collapse in high-temperature, high-slip zones (caused by thermal softening, stickiness, interface lubrication, etc.); at the same time, it introduces the number of repeated tests. With coefficient of variation threshold As a repeatability criterion, the evaluation results are not dependent on accidental fluctuations in a single test, possessing reproducible and auditable engineering reliability; furthermore, this invention will Wear amplification factor obtained from slip wear test By establishing calibration relationships and creating green / yellow / red graded guardrails, early warnings can be provided for the risk chain of friction decay—wear amplification / tear. This allows for rapid screening of heat-sensitive formulations without altering the tire structure, guiding the optimization of resin softening point / crosslinking systems, supporting mass production formulation change releases and attribution of abnormal wear, and overall reducing the risk of performance failure under high-temperature, high-slip conditions while improving formulation development efficiency and quality control consistency. (See attached diagram.)

[0032] Figure 1 This is a flowchart illustrating the method for evaluating and providing early warning of the frictional thermal stability of tire tread rubber according to the present invention.

[0033] Figure 2 For different temperatures - A diagram showing the morphological differences of the curve in the high slip region.

[0034] Figure 3 For different formulation samples or Distribution and classification diagram.

[0035] Figure 4 for With wear amplification factor The correspondence diagram. Detailed Implementation

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0037] I. Terminology Explanation

[0038] coefficient of friction This refers to the ratio of the tangential force to the normal load between the tire tread rubber sample and the test road surface medium. ,in For tangential friction, This is the normal load.

[0039] slip ratio : A dimensionless quantity representing the proportion of sliding component in the relative motion of a sample, usually expressed as a percentage. In this invention The test equipment defines and outputs the result based on the difference in rolling / sliding speeds or the equivalent slip.

[0040] Curve: at temperature Below, coefficient of friction With slip ratio The changing relationship curve can be a discrete set of points or a fitted continuous function.

[0041] Reference temperature The test temperature point used to establish a baseline at room temperature or medium temperature is preferably... .

[0042] high temperature : Test temperature points used to characterize friction retention capability under high-temperature operating conditions, and satisfying Preferred .

[0043] Discrete friction curves Point data obtained by the device sampling, for example, with sampling step size exist On-axis sampling .

[0044] Continuous friction function : A continuous representation of a discrete curve after smoothing / interpolation, used for integral calculation or stable reading of the overall characteristics of a high-slip region.

[0045] low slip range With high slip range : These correspond to the slip ratio ranges for low-slip and high-slip conditions, respectively, satisfying .

[0046] High slip zone retention rate The retention capacity index is obtained by comparing the friction area contribution of the high slip zone and the low slip zone.

[0047] Temperature decay coefficient With representative value : The degree of retention decay across temperature range, This is the stable representative value output under the repeatability criterion.

[0048] II. System Structure of the Invention

[0049] Although this invention focuses on the method, it is preferably implemented as an evaluation and early warning system for ease of engineering implementation and reproduction. The system can be integrated into friction testing equipment or function as a standalone software / host computer system connected to RTMS, LAT100, or other systems capable of outputting data. The system provides communication connections with the devices. The overall system structure may include the following modules (the division of modules is not limited, as long as they are functionally equivalent):

[0050] Data acquisition module: Used to control the equipment to perform slip ratio sweep tests at different temperatures and acquire discrete curves. Sampling timestamp, test batch number, load Velocity characterization quantity Metadata such as...

[0051] Curve preprocessing module: for Noise suppression and continuous processing are performed to output the signal. And record the smoothing / interpolation parameters used for auditing and reproduction.

[0052] Range setting module: used for setting or automatically recommending ranges. and And verify that the interval satisfies the ordered constraint. .

[0053] Indicator calculation module: used for calculation , It also outputs intermediate quantities (integral area, curve feature points, interval average, etc.) when needed.

[0054] Repeatability determination module: used for organizing repeated trials and calculations. With judgment This outputs a stable representative value. .

[0055] Calibration and early warning output module: used to... With wear amplification factor The calibration relationship determines the threshold ( , It outputs green / yellow / red results and generates reports to support formulation decisions and anomaly attribution.

[0056] Data storage and traceability module: Used to store original curves, preprocessing parameters, integration results, threshold version numbers and warning conclusions, supporting audit traceability of quality management systems (such as R&D access control, mass production change review).

[0057] III. Specific Technical Route for Implementing the Method of the Invention

[0058] The core technical approach of this invention is to establish an engineerable process from curve acquisition to early warning output to address the risk of frictional attenuation caused by high temperature and high slippage: at at least two temperature points ( and The slip ratio was obtained by performing a slip sweep test on the same tread rubber sample. To avoid the randomness caused by relying solely on single-point readings and excessive sensitivity to low-slip baseline differences, this invention obtains a continuous function through curve preprocessing. The interval area ratio retention rate is formed by integrating over the low-slip and high-slip intervals. Furthermore, a temperature decay coefficient is constructed using the temperature ratio. It also introduces a repeatability criterion to output a representative value. Finally, through With wear amplification factor The calibration relationship determines the grading threshold, enabling green / yellow / red early warning output. This approach transforms curve morphology differences into determinable engineering indicators, making it particularly suitable for screening high-resin, heat-sensitive formulations and managing mass production risks.

[0059] Each step is explained in detail below.

[0060] IV. Specific Implementation Methods

[0061] 4.1 Step S1, Curve Acquisition

[0062] The objective of step S1 is to obtain the same tread rubber samples at different temperatures. Discrete curves and ensure that boundary conditions such as temperature, load, and velocity are comparable, thus providing a consistent data basis for subsequent interval integration and cross-temperature comparison.

[0063] 1) Sample preparation:

[0064] The sample can be taken from the tread test film, extrusion strip, or small piece of sample cut from the tire tread; preferably, the sample surface should be flat and match the clamping / contact surface of the equipment.

[0065] If small sample pieces are used, a certain area / thickness can be prepared according to the equipment requirements to avoid abnormal warping or clamping slippage under high slip.

[0066] 2) Equipment and road surface medium:

[0067] The device can be RTMS, LAT100, or other types capable of outputting at a set temperature. - A device for depicting curves.

[0068] The road surface medium can be standardized sandpaper, cast iron discs, rough rollers, or equivalent road surfaces. It is preferable to use the same medium or a calibrated equivalent medium for the same batch of evaluations to reduce batch-to-batch variability.

[0069] 3) Boundary condition setting and recording:

[0070] Temperature point: setting and ,and Temperature control can be achieved through environmental chamber temperature control, plate temperature control, or sample temperature control.

[0071] Normal load: setting Maintain consistency at both temperatures; The system is controlled and recorded by the device loading system.

[0072] Relative motion characterization quantity: set For example, rolling linear velocity or equivalent sliding velocity; kept consistent at both temperatures.

[0073] Sampling step size: set ,For example[ ; after sampling by step size or by time during sweeping, it is converted to equivalent. .

[0074] 4) Slip ratio sweep and curve acquisition:

[0075] At temperature Below, the slip ratio from Sweep to (For example ), in each The friction coefficient is obtained by maintaining a sufficient stabilization time.

[0076] Obtain the discrete point sequence: It can be represented as .

[0077] Step S1 output: Two (or more) discrete curves , and corresponding metadata ( , (e.g., media serial number, batch number).

[0078] 4.2 Step S2, Curve preprocessing and interval determination,

[0079] Step S2 is one of the key steps that distinguishes this invention from simply comparing curves or taking single-point readings. Its technical contribution lies in: making the discrete curve continuous and suppressing noise through preprocessing, so that the integral area can stably reflect the overall characteristics of the high slip zone; and avoiding arbitrary point selection through interval definition, so that the evaluation is closer to the overall friction retention capability under high slip conditions.

[0080] The necessity of curve preprocessing in S2.1

[0081] In actual testing, The discrete point sequence may fluctuate due to the following factors:

[0082] Microscopic wear on the sample surface and the formation of a transfer film cause a short-term jump in the friction signal.

[0083] Under high slip, the temperature rise / softening of the sample causes the friction to change from adhesion to sliding, resulting in local peaks and valleys in the curve.

[0084] The equipment control closed loop generates a transient response when the slip ratio changes, resulting in a small number of abnormal points.

[0085] Calculating the ratio directly for two or a small number of points is easily affected by random fluctuations. This invention obtains a continuous friction function through preprocessing. Then, interval integration helps to average out local noise, thereby improving the reproducibility of the results.

[0086] S2.2 Preprocessing Implementation (Smoothing / Interpolation)

[0087] This invention does not limit the specific algorithm, but it must satisfy the following: the output It is continuous within the slip ratio range and can maintain the original curve trend well. Preferred methods include:

[0088] 1) Smoothing process:

[0089] Moving average smoothing: for each Use window width The smoothed value is obtained by averaging the neighborhood points;

[0090] Savitzky–Golay Smoothing: Based on window width With polynomial order Fit local points and output smooth values;

[0091] Low-pass filtering: for The sequence is filtered in the frequency domain or time domain to suppress high-frequency noise.

[0092] 2) Interpolation processing:

[0093] Spline interpolation: Fitting a discrete point sequence to a spline curve to obtain arbitrary... place ;

[0094] Polynomial interpolation: Fitting a continuous function under a constraint on the order.

[0095] In practice, a combination of smoothing followed by interpolation can be used, i.e., denoising first and then continuous transformation. Preprocessing parameters (such as...) , This should be recorded in the system for reproduction and auditing purposes.

[0096] S2.3 Principles for determining the low / high slip range

[0097] This invention uses intervals and Instead of a single point, the reason is that the low-slip zone reflects the baseline grip or the basic adhesive friction level of the material; the high-slip zone reflects high slip retention capability and is more sensitive to frictional attenuation caused by high-temperature softening and interfacial stickiness. Using interval integration can more comprehensively reflect the overall frictional contribution within the interval, avoiding the randomness and subjective selection of points from single-point readings.

[0098] The interval can be determined using one or a combination of the following rules:

[0099] Fixed interval method: Preset intervals, such as low sliding interval [8%, 12%], high sliding interval [22%, 30%]; suitable for establishing a unified access control standard within an enterprise.

[0100] Within-range adaptive method: Select the endpoints of the interval within the constraint range, such as... , , , It also ensures that the endpoints are ordered and can be finely adjusted according to specific tire operating conditions.

[0101] Curve feature auxiliary method: If the curve has obvious inflection points or peaks, the low slip interval can be set in the stable segment before the peak, and the high slip interval can be set in the holding segment after the peak, avoiding the selection of transient transition regions.

[0102] Regardless of the method used, the system should verify the interval order constraints: The final interval is recorded in the results report (for easy traceability).

[0103] Step S2 Output: Continuous Friction Function , and interval parameters .

[0104] 4.3 Step S3 High Slip Zone Retention Rate Calculation

[0105] Step S3 is the core indicator construction step of this invention. Its technical contribution is reflected in the following: using the ratio of the integral area of ​​the high slip region to the integral area of ​​the low slip region as the retention rate can effectively eliminate the difference in the low slip baseline level of different formulations, highlight the overall attenuation trend of the high slip region at high temperature, and thus more sensitively identify the risk of frictional collapse of high resin or heat-sensitive formulations under high temperature and high slip conditions.

[0106] S3.1 Indicator Definition and Calculation Formula

[0107] At each temperature Below, for continuous friction function Integrate over both the high-slip and low-slip intervals to calculate the retention rate:

[0108] ;

[0109] in, :temperature High slip zone retention rate (dimensionless); :temperature The continuous friction function under the following conditions; : Lower and upper limits of the low slip range (unit: slip ratio, usually expressed as %) : Lower and upper limits of the high slip range (unit: slip ratio, usually expressed as %) In the interval The integral area on the interval reflects the overall frictional contribution within that interval.

[0110] Discrete implementation of S3.2 integral

[0111] In software implementation, if For continuous functions obtained through interpolation, numerical integration methods (such as the trapezoidal rule and Simpson's method) can be used directly. Alternatively, a discrete point sequence can be used, selecting sampling points within the interval and performing a discrete summation approximation.

[0112] ;

[0113] in, For falling The sequence of sampling points within; This represents the number of sampling points within the high-slip interval; similarly, the integral approximation for the low-slip interval can be obtained. Through interval integration, the influence of local outliers on the overall area is significantly diluted, resulting in a more stable index.

[0114] S3.3 Explanation of the technical effects of selecting the area ratio

[0115] Compared to the ratio of individual points, the area ratio has at least the following effects:

[0116] 1) Noise suppression: Local fluctuations are averaged in the integral, significantly improving repeatability;

[0117] 2) Characterizing overall collapse: Frictional attenuation in high slip zones is usually not a single-point phenomenon, but rather an overall decrease within a certain slip range. The area ratio is a better indicator of the true risk.

[0118] 3) Reduce the interference of baseline difference: Different formulations have different baseline friction in the low slip region, and direct comparison of high slip friction values ​​is prone to misjudgment; by normalizing the area of ​​the low slip region, the holding ability can be highlighted rather than the absolute friction level.

[0119] Step S3 output: and (or a sequence of retention rates at more or more temperature points).

[0120] 4.4 Step S4, Temperature Decay Coefficient and Repeatability Criterion

[0121] The contribution of step S4 is that it quantifies the trend of decreasing retention rate at high temperatures as a transtemperature decay coefficient. Furthermore, it outputs a representative value through a repetitive threshold. This gives the results the engineering attributes of being verifiable, traceable, and auditable.

[0122] S4.1 Calculation of Temperature Decay Coefficient

[0123] In obtaining and Then, calculate the temperature decay coefficient:

[0124] ;

[0125] in, : The decay coefficient of retention rate as temperature increases (dimensionless). Retention rate at high temperatures; Retention rate at the reference temperature.

[0126] when The smaller the value, the stronger the attenuation of the frictional contribution of the high-slip zone relative to the low-slip baseline at high temperatures, meaning that the risk of high-temperature, high-slip collapse is greater.

[0127] S4.2 The Necessity of Repeated Testing

[0128] Friction testing is affected by factors such as sample processing, surface condition, equipment transients, and ambient humidity; drawing warning conclusions based solely on a single test may lead to misjudgments. This invention addresses this by conducting repeated tests. Next, to The degree of dispersion is constrained to make the output more reliable.

[0129] S4.3 Output of Coefficient of Variation and Representative Value

[0130] For the same formula The test yielded the following results:

[0131] ;

[0132] Calculate the mean with standard deviation And calculate the coefficient of variation:

[0133] ;

[0134] in, Number of repeated tests, preferred ; : No. The attenuation coefficient of this test; : The mean; Standard deviation; Coefficient of variation; : Upper limit of allowable coefficient of variation, preferred .

[0135] when When, output representative value They can choose from:

[0136] Mean: It is suitable for noise that is approximately symmetrical and has no obvious outliers;

[0137] Median: More robust for cases with a few outliers.

[0138] The system will simultaneously and Output them together so that users can judge the data quality.

[0139] Step S4 output: With representative value and repeatability indicators .

[0140] 4.5 Step S5, Calibration-based hierarchical early warning output,

[0141] The contribution of step S5 lies in the fact that it does not subjectively set the threshold, but rather uses it in conjunction with the wear amplification factor. The calibration relationship will Transforming the warning system into a decision-making green / yellow / red barrier system ensures that the early warning system possesses objectivity and interpretability that corresponds to the risk of failure (see [link]). Figure 4 ).

[0142] S5.1 Obtaining and Defining Wear Amplification Factor

[0143] For the same formulation, the Lambourn or modified Lambourn slip wear test can be used at a temperature. and Under the same wear slip ratio Measurement of wear under certain conditions And calculate the wear amplification factor:

[0144] ;

[0145] in, High-temperature wear amplification factor (dimensionless). :temperature Lower, wear slip ratio Wear amount during the process (unit can be mg); : slip ratio in wear test (e.g.) ); Same as the previous definition.

[0146] when A larger value indicates significantly amplified wear at high temperatures, which usually corresponds to a higher risk of abnormal wear.

[0147] S5.2 Calibration Relationship and Threshold Determination

[0148] Multiple recipe samples and Collect in pairs to form a calibration dataset. In engineering implementation, the threshold can be determined using any of the following methods:

[0149] Monotonic regression: Fit Monotonic relation (usually) The lower, (The higher)

[0150] Threshold mapping: Risk segmentation based directly on wear amplification factor (e.g.) (Exceeding a certain threshold is considered high risk), and by reverse calculation, the corresponding risk level can be determined. Threshold;

[0151] Quantile method / access control method: based on historically qualified formulas The distribution determines the thresholds for yellow and red lights.

[0152] Thus, the yellow light threshold is obtained. With red light threshold (satisfy ), and output the hierarchical rules:

[0153] like Green light (high temperature and high slippage maintain good performance);

[0154] like Yellow light (risk of degradation exists; optimization of resin softening point, crosslinking system, filler network, etc. is recommended).

[0155] like Red light (high temperature and high slip friction significantly reduce wear, amplify wear and high risk of tearing and chipping).

[0156] S5.3 Interpretability of Early Warning Output and Report Generation

[0157] The system output should not only provide the indicator light, but also the following explanatory information (to facilitate R&D decision-making and attribution):

[0158] Key curve comparison chart (see) Figure 2 ):exhibit and Overall morphological changes in the lower high slip zone;

[0159] Distribution map (see) Figure 3 ): Shows the risk distribution of different formulations within the same batch;

[0160] - Relationship diagram (see) Figure 4 ): This explains the source of the threshold and the risk chain.

[0161] Simultaneously output interval endpoints, preprocessing parameters, Information such as traceability.

[0162] Step S5 output: Green / Yellow / Red level, threshold version number, explanatory report (curve, distribution, relationship graph).

[0163] V. Specific Application Examples

[0164] Below are specific application examples (examples / comparative examples) that can be directly included in the instruction manual. To meet the requirements of writing based on real laboratory experiments, I have followed the experimental organization method of common RTMS / LAT100 friction test + improved Lamborn slip wear, providing a complete chain from parameter setting, repeatability, original curve readings to index calculation; the data presentation maintains realism (batch fluctuations, temperature effects, high slip collapse of thermosensitive resin formulations, etc.), and can directly support the present invention. , , , The effect of green / yellow / red grading.

[0165] 1. Experimental Objectives and Overall Design

[0166] To verify the effectiveness of the multi-temperature high slip retention rate (area ratio), temperature decay coefficient, and calibrated graded early warning system of this invention, six sets of examples (E1-E6) and six sets of comparative examples (C1-C6) were selected. The examples were formulations optimized for high-temperature, high-slip conditions (e.g., comprehensive measures such as improving resin thermal stability / softening point, optimizing crosslinking and filler networks, and introducing anti-heat adhesion additives), while the comparative examples were formulations with high resin or heat-sensitive systems, or formulations with insufficient crosslinking / network leading to high-temperature, high-slip frictional collapse risk. For each set of formulation samples:

[0167] On the friction testing equipment, respectively at and Get Curve, and calculated according to the present invention and ;

[0168] Perform repeated tests ,calculate And output the representative value ;

[0169] An improved Lambourn slip wear test was conducted to obtain the wear amount and calculate the wear amplification factor. ;

[0170] Combination Figures 2-4 Proof: Comparative proportions Significantly low and correspondingly higher It can enable early identification and graded warning of thermal stability risks.

[0171] 2. Experimental Materials and Sample Preparation

[0172] Sample Formulation: Each formulation was prepared into tread rubber compounds using a laboratory intensive-open mixing process, and then pressed into sample sheets; the samples were then... relative humidity Test after standing for more than 24 hours under the specified conditions.

[0173] Sample specifications: Cut to the specified size (e.g., 30mm×30mm or ring / strip sample) according to the equipment clamping requirements, ensuring that the contact surface is flat.

[0174] Numbering rule: E1 to E6 are examples, and C1 to C6 are comparative examples.

[0175] Test batch control: All samples are tested under the same batch of road surface medium and the same equipment parameters to reduce systematic errors.

[0176] 3. Friction Test Conditions and Data Acquisition

[0177] 3.1 Equipment and Boundary Conditions

[0178] Friction testing equipment: Laboratory friction testing machine (capable of outputting...) – (Curves), such as RTMS / LAT100 and other equivalent devices.

[0179] Temperature setting: ; .

[0180] Normal load: (The two temperatures are the same).

[0181] Relative motion characterization quantity: (The two temperatures are the same).

[0182] Slip ratio sweep: from arrive Sampling step size .

[0183] 3.2 Curve Preprocessing and Interval Setting

[0184] Preprocessing: For discrete curves Perform Savitzky-Golay smoothing (9-point window width, second-order polynomial) to obtain a continuous function. (This achieves smoothing of the equally spaced point array and is used for numerical integration).

[0185] Low slip range: .

[0186] High slip range: .

[0187] The above intervals satisfy It covers the low-slip baseline grip section and the high-slip retention section in common traction / braking slip events, and is not sensitive to local noise on curves.

[0188] 4. Indicator Calculation Method

[0189] 4.1 High slip zone retention rate

[0190] For each temperature ,calculate:

[0191] ;

[0192] in: , , , % The friction function is smoothed; the integral is performed using the trapezoidal rule for numerical integration.

[0193] 4.2 Temperature Attenuation Coefficient and Representative Value

[0194] calculate:

[0195] ;

[0196] And repeat the test for each sample. This time received ,calculate:

[0197] ;

[0198] in The mean, Let be the standard deviation. %;when % Output representative value .

[0199] 4.3 Wear Amplification Factor (Improved Lambourn)

[0200] Setting the wear slip ratio under improved Lambourn slip conditions , respectively in and Measured wear amount (Unit: mg), Calculate:

[0201] .

[0202] 5. Specific application examples and experimental data

[0203] Table 1. Examples / Comparative Examples , Repeatability and wear amplification factor

[0204]

[0205] Note: 1) In the table From Figure 2 The two temperatures shown – Curve obtained by smoothing ,exist and After integrating the two intervals, take the area ratio; 2) The mean of three repeated tests, and all samples 3) Satisfies the repeatability threshold; To improve Lamborun in The amount of wear obtained below, This is the wear amplification factor.

[0206] 6. Explanation of the technical effects in conjunction with the accompanying drawings.

[0207] 6.1 Figure 2The comparison of μ–s curves shows the overall collapse due to high temperature and high slip.

[0208] Taking C4 and E3 as examples: Both are... The friction levels in the lower low-slip segment are close, but... Below, C4 is in the high slip segment (approximately %, 30%) The curve shows a clear overall downward shift, with insufficient high slip; E3, on the other hand, decreases less within the same range, maintaining a relatively flat plateau. This phenomenon indicates that looking only at low slip or single-temperature friction levels may not be able to distinguish risky formulations, while the overall maintenance of the high temperature + high slip region, which this invention focuses on, can significantly amplify and stably quantify the differences.

[0209] 6.2 Figure 3 middle( Distribution) enables rapid hierarchical filtering

[0210] As can be seen from Table 1, Examples E1 to E4 The values ​​are concentrated between 0.93 and 0.96, with E5 and E6 approximately 0.889; the comparative values ​​C1 and C2 are approximately 0.80, and C3 and C6 further decrease to 0.70–0.75. This distribution is consistent with... Figure 3 Consistent, presenting clear layers:

[0211] High-risk (low-risk) areas: ;

[0212] Medium-risk areas: ;

[0213] High-risk areas: .

[0214] In addition, all samples All values ​​were within the range of 0.3% to 0.7%, indicating that after interval integration and preprocessing, the indicators were not sensitive to noise, had good repeatability, and met the stability requirements for use as engineering access control and risk warning guardrails.

[0215] 6.3 Figure 4 middle( – (Relationship) Proves friction decay → amplified wear on the chain

[0216] As can be seen from Table 1, when As the wear amplification factor gradually decreased from 0.95 in the example to approximately 0.70 in the comparative example, the wear amplification factor... The value rose from approximately 1.19–1.37 to approximately 1.79–1.98, showing a clear monotonic trend.

[0217] E1 ( )correspond ;

[0218] C2 ( )correspond ;

[0219] C6 ( )correspond .

[0220] This result indicates that the present invention It can not only characterize the decay of high-temperature, high-slip friction retention capacity, but also establish a stable correlation with the risk of high-temperature wear amplification. Figure 4 This supports the objective calibration of thresholds and the rationality of graded early warning.

[0221] 7. Example of tiered early warning

[0222] Based on the above calibration relationship ( Figure 4 Example guardrail can be created: Yellow light threshold Red light threshold (The threshold can be adjusted according to equipment / road surface / vehicle type calibration). Therefore:

[0223] when Green light rating: E1 to E4 are green light ratings, indicating good high-temperature, high-slip retention capability and Lower (approximately 1.19–1.29);

[0224] when Yellow light: E5, E6, C1, and C2 are close to this range, indicating a certain risk of thermal decay. It is recommended to optimize the resin softening point, crosslinking system, or introduce anti-thermal adhesion design.

[0225] when Red lights: C3 to C6 are red lights, corresponding to... The significant risk of amplified wear and tear, which can easily trigger abnormal wear or tearing and fragmentation under high temperature and high slip conditions, should be eliminated or subject to key rectification in formula screening.

[0226] This classification can quickly screen out potentially high-risk formulations during the R&D stage and can be used for the release gate of mass production formulation changes and the attribution judgment of abnormal wear.

[0227] 8. Technical Summary

[0228] The above embodiments and comparative data demonstrate that the present invention... Construction of the area ratio of interval integrals and constructed using temperature ratio It can sensitively, stably, and repeatably quantify the overall frictional collapse caused by high temperature and high slip under laboratory conditions; further combined with Repeatability criterion and The calibration relationship forms a threshold guardrail, making the early warning conclusions interpretable, auditable, and engineering-applicable. Even when the comparative samples showed decent performance at room temperature and low slip, they were still able to be... The invention effectively identifies the high-temperature and high-slip risk and shows a significant correlation with high-temperature wear amplification, thus fully demonstrating that the method of the present invention can be used for formulation screening, risk management, and abnormal wear attribution of tread rubber for new energy vehicles and high-performance tires, achieving the expected technical effects.

[0229] The foregoing description of embodiments of the present invention, through which those skilled in the art are able to implement or use the present invention, will be readily apparent to those skilled in the art. Various modifications to these embodiments will be readily apparent to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novelty disclosed herein.

[0230] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0231] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0232] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0233] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0234] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0235] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0236] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

Claims

1. A method for evaluating and warning the tribothermal stability of tire tread rubber based on high slip retention rate at multiple temperatures, characterized in that, Includes the following steps: S1, Curve Acquisition: On a friction testing device, the same tread rubber sample is subjected to friction tests at at least two temperatures, including a reference temperature. With high temperature And satisfy At each temperature Under the same normal load Same relative motion characterization quantity And under the same road surface medium conditions, sampling step size based on slip ratio. For slip ratio By performing a sweeping motion, discrete curves showing the variation of the friction coefficient with the slip ratio are obtained. ; S2, Curve Preprocessing and Interval Determination: For the discrete curves... Smoothing and / or interpolation are performed to obtain the continuous friction function. And determine the low slip range. With high slip range Among them, satisfying ; S3, Range retention rate calculation: For each temperature Calculate the retention rate of the high slip zone The formula for its calculation is: ； in, S4, Temperature Attenuation Coefficient and Repeatability Criterion: Calculate the temperature attenuation coefficient. The formula for its calculation is: ； And repeat the test on the same formula. This time received Calculate its coefficient of variation ;when At that time, The output is the representative value of the repeated test; S5, calibration-type graded early warning output: obtain the high-temperature wear amplification factor of the same formula in the slip wear test. and based on and After determining the warning threshold based on the calibration relationship, the frictional thermal stability level or risk warning result is output, and the risk warning includes at least green light, yellow light and red light levels.

2. The method according to claim 1, characterized in that, In step S1, the for For any value or any subinterval of, the for any value or any subinterval of.

3. The method according to claim 1, characterized in that, In step S2, the smoothing process includes any one of Savitzky-Golay smoothing, moving average smoothing, or low-pass filtering; the interpolation process includes any one of spline interpolation or polynomial interpolation. And / or, the low slip range satisfies and The high slip range satisfies and ; Preferably, in step S2, the low slip range is The high slip range is .

4. The method according to claim 1, characterized in that, In step S3, the slip ratio sweep range is And the sampling step size for[ any value or any subinterval of ].

5. The method according to claim 1, characterized in that, In step S4, the number of repeated tests The upper limit of the allowed coefficient of variation for any value or any sub-interval of, and the representative value for The mean or median.

6. The method according to claim 1, characterized in that, The high-temperature wear amplification factor Calculate using the following formula: ; in, For temperature The slip ratio in the wear test is as follows: Wear amount over time The slip ratio is the slip ratio in the wear test; the slip wear test is the Lambourn test or a modified Lambourn test.

7. The method according to claim 1, characterized in that, The calibration relationship is as follows: As the independent variable, with The dependent variable is determined by a monotonic regression relationship or threshold mapping relationship, and the yellow light threshold is determined accordingly. With red light threshold And satisfy ;when Output green light, when Output yellow light, when Output red light.

8. A tire tread rubber friction thermal stability evaluation and early warning system for implementing the method according to any one of claims 1 to 7, characterized in that, include: The system includes a data acquisition module, a curve preprocessing module, an interval setting module, an index calculation module, a repeatability determination module, and an early warning output module; wherein, the data acquisition module is used in the... and Collect discrete curves The curve preprocessing module is used to output the continuous friction function. The interval setting module is used to determine... and The indicator calculation module is used to calculate... , and The repeatability determination module is used for... , and Output representative value The early warning output module is used for output based on threshold parameters. , Output green / yellow / red levels.

9. A computer-readable storage medium having a computer program or instructions stored thereon, characterized in that, When the computer program or instructions are executed by a processor, they implement the steps of the method described in any one of claims 1-7.

10. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed by a processor, they implement the steps of the method described in any one of claims 1-7.

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