Method for evaluating the impact strength of a rubber element

Abstract

A method for evaluating the impact resistance of a rubber element, comprising the following step: Evaluating the impact performance of the rubber element using an elongation at break Eb, a tear strength TSb and a loss tangent tan δ of the rubber element; wherein a measurement condition of the loss tangent tan δ used in the step of evaluating the impact resistance performance is determined based on a speed of an impact applied under use conditions of the rubber member, wherein the loss tangent tan δ is a relationship between a storage modulus and a loss modulus calculated from a stress when vibrations of a predetermined frequency are applied to the rubber element; and the predetermined frequency of the measurement condition is determined by adjusting the speed of an impact exerted under conditions of use of the rubber element to a maximum speed of the vibrations, and wherein the rubber member is a cover rubber covering a belt core body of a conveyor belt and having the predetermined frequency of 10 kHz.

Description

Technical area

[0001] The present invention relates to a method for evaluating the impact resistance of a rubber member. State of the art

[0002] In the prior art, mechanical strength indicators such as elongation at break (Eb) and tear strength (TSb) are used as performance evaluation indicators for rubber elements such as conveyor belts. For example, when a conveyed object is loaded onto a conveyor belt, the conveyed object may strongly impact the cover rubber covering a core body, causing shear damage on the surface of the cover rubber. To reduce this shear damage, rubber with high mechanical strength (elongation at break (Eb) and tear strength (TSb)) has been developed.

[0003] A known method for evaluating this type of rubber material includes a DIN abrasion test, in which a rubber material test piece is pressed onto a cylindrical member with an abrasive cloth wound around its outer peripheral surface, the cylindrical member makes a predetermined number of rotations, and the amount of wear of the test piece is measured. Furthermore, as a known method for evaluating the durability of a rubber material for a conveyor belt, a method has been proposed in which the durability of a rubber material is evaluated based on how much the weight of a rubber material test piece for a conveyor belt is reduced by abrasive blasting the test piece for a predetermined period of time (see Patent Document 1 below).As described in Patent Document 1, when the granules collide with the surface of the test piece, a large impact force is exerted on the surface of the test piece, and the surface of the test piece is abraded by the impact force applied many times. In other words, the test piece can be subjected to wear similar to the wear actually experienced by a conveyor belt, so it is possible to replicate the durability of an actual conveyor belt. Patent Document 2 describes a rubber composition consisting of natural rubber and styrene-butadiene rubber, comprising 100 parts by weight of rubber, the mixing ratio (weight ratio) of natural rubber and styrene-butadiene rubber being 50 / 50 to 80 / 20, 45 to 65 parts by weight of ultrafine carbon black, 5 to 20 parts by weight of silica, and 2 to 7 parts by weight of resin. Patent Document 3 discloses an impact testing apparatus.A weight is connected to an actuator, and a drive source controller is controlled by a CPU display to drive and stop a driver, causing the actuator to move at a specified speed. After the actuator reaches the specified speed, it stops to eject the weight. The speed of the weight is measured using the output of an optical non-contact displacement detection sensor and stored in RAM via a high-speed A / D conversion memory. When the weight collides with a sample, the contact time between the weight and the sample is measured using the output of a pressure sensor, and the return speed of the weight is measured using the sensor output. The CPU uses the RAM storage data to calculate characteristics such as the angular frequency of strain and output them.Patent Document 4 discloses the provision of a method for predicting the heat generation of a treadmill, a method for predicting the running resistance force, a method for predicting the heat generation of a rotating body during running, and a method for predicting the rolling resistance. A master curve showing the frequency and temperature characteristics of the loss factor tan δ of a viscoelastic material is constructed. Then, the frequency of the waveform representing stress or strain is calculated from the first to the Nth order using the running speed of the specified unit belt body. The loss factor tan δ corresponding to each frequency is obtained from the master curve using the specified temperature. Literature listPatent literature Patent document 1: JP 2008 - 224 510 A Patent document 2: JP 2000 - 198 517 A Patent document 3: JP S63 - 1 950 A Patent document 4: JP 2009 - 222 656 A Brief description of the inventionTechnical problem

[0004] There is a need to develop rubber element products, such as conveyor belts, that can withstand impacts during use and that exhibit high abrasion resistance and high impact performance. Impact performance depends on both the mechanical strength, as described above, and the energy-absorbing properties of the rubber (hysteresis loss due to viscosity). However, quantitative evaluations of these are rare, and there is room for improvement. For example, for the loss tangent tan δ, which is an indicator of the viscoelastic characteristics of a rubber element, from the perspective of simplifying the measurement, the value at room temperature and several tens of Hz is used, but the viscosity of the rubber element depends on the speed, and thus the viscosity characteristics of a speed range (frequency range) should be evaluated according to the application. In view of the above, it is an object of the present invention to quantitatively evaluate the impact resistance performance of a rubber member. Solution to the problem

[0005] To achieve the above-described object, a method for evaluating the impact resistance of a rubber member according to one aspect of the present invention comprises the following step: Evaluating the impact performance of the rubber element using an elongation at break Eb, a tear strength TSb and a loss tangent tan δ of the rubber element; where a measurement condition of the loss tangent tan δ used in the step of evaluating the impact resistance performance is determined based on a speed of an impact applied under use conditions of the rubber member, wherein the loss tangent tan δ is a ratio between a storage modulus and a loss modulus calculated from a stress, when vibrations of a predetermined frequency are applied to the rubber element; and the predetermined frequency of the measurement condition is determined by adjusting the speed of an impact exerted under conditions of use of the rubber element to a maximum speed of the vibrations, and wherein the rubber member is a cover rubber covering a belt core body of a conveyor belt and having the predetermined frequency of 10 kHz. In the method for evaluating the impact resistance of a rubber member according to another aspect of the present invention, a frequency characteristic curve indicating a relationship between the loss tangent tan δ and a frequency of vibrations, and a temperature characteristic curve showing a relationship between the loss tangent tan δ and a temperature of the rubber element, substitutable; and the loss tangent tan δ used in the step of evaluating the impact resistance performance is calculated by calculating the temperature corresponding to the predetermined frequency based on the relationship between the frequency characteristic and the temperature characteristic and using stress when vibration is applied to the rubber member at the temperature. In the method for evaluating the impact resistance of a rubber member according to another aspect of the present invention, when an impact performance evaluation index of the rubber member is defined as a product of the elongation at break Eb, the tear strength TSb and the loss tangent tan δ of the rubber member, and When the impact performance calculated using the loss tangent tan δ at the predetermined frequency of 10 kHz is 6,000 or greater, the impact performance is determined to be high. In the method for evaluating the impact resistance of a rubber member according to another aspect of the present invention, a higher value for the impact performance evaluation index of the rubber member indicates high impact performance of the rubber member. Advantageous effects of the invention

[0006] According to the invention according to one aspect of the present invention, when evaluating the impact resistance performance of the rubber member using the elongation at break Eb, the tensile strength TSb, and the loss tangent tan δ of the rubber member, the measurement condition of the loss tangent tan δ used in the impact resistance performance evaluation is determined based on the speed of the impact applied under the use conditions of the rubber member. As a result, the impact resistance performance can be evaluated using the value of the loss tangent tan δ corresponding to an impact actually applied to the rubber member, and it is possible to improve the accuracy of the impact resistance performance evaluation. According to this aspect of the present invention, the measurement frequency (a predetermined frequency) of the loss tangent tan δ is determined by adjusting the speed of impact applied under the use conditions of the rubber member to the maximum speed of vibrations, and thus the impact resistance performance can be evaluated by reflecting the viscosity of the rubber member which changes depending on the speed of impact. According to the invention according to a further aspect of the invention, even in a case where the measurement of the loss tangent tan δ is carried out at different temperatures instead of different frequencies, the value of the loss tangent tan δ corresponding to an impact actually applied when the rubber member is in use can be calculated. According to the invention of the first aspect of the invention, the impact resistance performance of the cover rubber of the conveyor belt can be easily and accurately evaluated. According to the invention according to a further aspect of the invention, it is possible to provide a conveyor belt having sufficient impact resistance performance in its intended use environment. According to the invention according to another aspect of the invention, the elongation at break Eb, the tear strength TSb and the loss tangent tan δ can be easily unified and compared, and it is possible to provide an evaluation index that clearly reflects the impact resistance performance of the rubber member. Brief description of the drawings Fig. 1 is a flowchart illustrating the process of a method for evaluating impact strength according to one embodiment. Fig. 2 is an explanatory diagram of a method for determining an evaluation frequency based on a speed of an impact. Fig. 3 is an explanatory diagram of a method for determining an evaluation frequency based on a speed of an impact. Fig. Figure 4 is a graph showing a principal curve of a loss tangent tan δ. Fig. Figure 5 is a table listing performance evaluation values ​​and performance evaluation test results of samples A to C. Fig. 6A to 6C are surface photographs of a conveyor belt cover rubber after use for a predetermined period of time. Fig. Figure 7 is a graph showing the impact performance evaluation index (Eb × TSb × tan δ) of samples A to C. Description of embodiments

[0007] A method for evaluating the impact resistance of a rubber member according to preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Fig. 1 is a flowchart illustrating the process of a method for evaluating impact strength according to one embodiment. In the present embodiment, the elongation at break Eb, the tensile strength TSb, and the loss tangent tan δ of the rubber member are used to evaluate the impact resistance performance of the rubber member. Furthermore, in the present embodiment, the rubber member to be evaluated is a cover rubber covering a core body of a conveyor belt. In Fig. 1 the individual steps are ordered for the sake of clarity, but the order in which the parameters are measured, for example, can be interchangeable.

[0008] First, the elongation at break Eb and the tear strength TSb of the rubber element are measured (step S10). The elongation at break (Eb) and the tensile strength (TSb) are measured using a method that involves pulling a test piece of the rubber element being evaluated. The elongation at break (Eb) is the elongation at which the test piece fails due to pulling and is expressed as a ratio (%) relative to an initial distance between reference lines. The tensile strength (TSb) is the tensile force recorded when the test piece fails due to pulling divided by the initial cross-sectional area of ​​the test piece. The exact process of measuring elongation at break Eb and tear strength TSb is determined by the process specified in JIS K6251: Vulcanized rubber and thermoplastic rubber - Tensile properties.

[0009] Next, the loss tangent tan δ of the rubber element is measured (step S12). The loss tangent (tan δ) is the ratio between the storage modulus and the loss modulus, calculated from the stress when vibrations are applied to the rubber element at a predetermined frequency. It is the ratio of the loss modulus to the storage modulus in dynamic viscoelasticity measurements. Higher values ​​indicate higher viscosity and greater performance in converting kinetic energy into heat. Furthermore, when the viscosity is high, the apparent hardness of the impact point increases, which has the effect of distributing stress to the surrounding area and reducing the amount by which the object sinks into the rubber element. Thus, a high loss tangent tan δ of the rubber element indicates high impact performance.

[0010] The measurement of the loss tangent tan δ of the rubber element is generally carried out using a device for dynamic Viscoelasticity measurement. In a dynamic viscoelasticity measurement device, a rubber member sample is clamped in the measuring head, and stress is applied to the sample from the load-generating section via a probe. This stress is applied as a sinusoidal force at a frequency specified as one of the measurement conditions, in such a way that the stress amplitude of the sample is constant. The amount of deformation (distortion) of the sample caused by this sinusoidal force is detected by a displacement detection unit, and various types of viscoelastic quantities, such as the loss tangent (tan δ), are calculated from the stress applied to the sample and the detected distortion and output. If the temperature is constant, as in Fig. As illustrated in Figure 4, a main curve is obtained with a frequency on the x-axis and tan δ (alternatively storage modulus or loss modulus are also possible) on the y-axis.

[0011] Fig. Figure 4 shows the loss tangent tan δ of three types of rubber elements (samples A to C). Sample A is an internally developed impact strength example. Sample B is a rubber type H compliant product (JIS-H compliant), as specified in JIS K6369. Sample C is a rubber type S compliant product (JIS-S compliant), as specified in JIS K6369. The loss tangent tan δ of each rubber element increases from a low frequency band to a high frequency band as a whole, but the frequency characteristics are different from each other. It should be noted that the thickness of the conveyor belt cover rubber is typically 5 mm to 25 mm. In this example, a sample with a thickness of 10 mm was used. Additionally, the temperature condition was set to 20 °C.

[0012] In addition, in practice, in a case where a main curve with a frequency axis as in Fig. 4 illustrates that the measurement is performed by changing the temperature of the sample rather than changing the vibration frequency. This is because the frequency characteristic curve, which indicates the relationship between the loss tangent tan δ and the vibration frequency, and a temperature characteristic curve, which indicates the relationship between the loss tangent tan δ and the ambient temperature at which the measurement is performed, can be converted into each other. A known method for converting the frequency characteristic and the temperature characteristic can be used, and therefore its description is omitted. However, a loss tangent tan δ at low temperatures corresponds to a loss tangent tan δ in a high frequency band, and a loss tangent tan δ at high temperatures corresponds to a loss tan δ in a low frequency band.

[0013] Next, the frequency (evaluation frequency) of the loss tangent tan δ used in the evaluation of impact performance is determined (step S14). As described above, in step S12, a loss tangent tan δ is obtained as a frequency characteristic curve obtained by plotting the frequency on the x-axis. In step S14, the loss tangent tan δ used in the impact strength performance evaluation is determined from the main curve. In particular, the evaluation frequency, which is the frequency of the loss tangent tan δ used to evaluate the impact resistance performance, is determined by adjusting the speed of the impact exerted under the use conditions of the rubber element to the maximum speed of the vibrations.

[0014] A method for determining the evaluation frequency based on the speed of impact is described using Fig. 2 and Fig. 3 described. For example, if the rubber element being evaluated is a cover rubber covering the core body of the conveyor belt, the impact exerted under the use conditions of the rubber element is an impact when the conveyed object is loaded. Generally, objects conveyed on a conveyor belt are dropped from a position higher than the conveyor belt surface (cover rubber surface) via a chute or the like and loaded onto the conveyor belt. A drop velocity Vf when the conveyed object lands on the conveyor belt is determined based on a drop height H of the conveyed object. In other words, V = √2gH (g: gravitational acceleration). Fig. Figure 2 is a graph showing the relationship between the drop height H of the conveyed object and the drop speed Vf when the conveyed object reaches the conveyor belt. For example, in a case where the conveyed object on the conveyor belt is ore or the like, the drop height H is high, approximately 8 m. In this case, the drop speed Vf when the conveyed object reaches the conveyor belt is approximately 12.5 m / s.

[0015] In the case where the discharge height H is relatively low, for example, at about 0.5 m, the discharge speed Vf when the conveyed object reaches the conveyor belt is approximately 3.1 m / s.

[0016] Next, the maximum speed of vibrations in the dynamic viscoelasticity measurement is considered to determine the relationship between the shedding speed Vf and the measurement conditions of the loss tangent tan δ. As in Fig. As shown in Figure 3, for a sine wave with an amplitude A and a frequency f (angular frequency ω = 2nf), a displacement U = Asin(ωt) and a velocity V = Aωcos(ωt). A maximum velocity Vx is obtained at cos0° = 1 and Vx = Aω = 2nAf. If the above-discussed release velocity Vf is substituted for the maximum velocity Vx, then f = Vf / 2nA applies. If the amplitude A of the sine wave is 0.1 mm and the above-described drop velocity Vf is set to 3.1 m / s (drop from a height of 0.5 m) to 12.5 m / s (drop from a height of 8 m), the frequency f of the sine wave is from 4.9 kHz (drop from a height of 0.5 m) to 19.9 kHz (drop from a height of 8 m). This range corresponds to the shaded portion (log f = approximately 3.7 to 4.3) of the graph of tan δ in Fig. 4. In this range, the tan δ of sample A is the highest, then sample C, then sample B.

[0017] To avoid damage to the cover rubber when dropping objects (conveyed objects) onto the cover rubber, the mechanical strength should be high at the point where the dropped object sinks deepest into the cover rubber. Since the dropped object has a velocity of zero in a drop direction, it is reasonable to use the laboratory-measured elongation at break (Eb) and tensile strength (TSb) without change as indicators of mechanical strength. However, since the energy absorbing properties at the initial impact time are affected by the initial speed at which the dropped object comes into contact with the cover rubber, it is appropriate to determine the tan δ, which represents the viscosity of the rubber element, taking into account the speed of the impact exerted under the conditions of use of the rubber element. For example, if the cover rubber is used in an environment where the conveyed object is dropped from a height of 0.5 m, the evaluation frequency is 4.9 kHz, and if the cover rubber is used in an environment where the conveyed object is dropped from a height of 8 m, the evaluation frequency is 19.9 kHz.

[0018] During the manufacturing phase of the rubber element, it is not possible to know in detail the environment in which the rubber element will actually be used, making it difficult to specify the evaluation frequency. Therefore, if the rubber element to be evaluated is a cover rubber covering a core body of a conveyor belt, as described above, 10 kHz is used as a representative value for the evaluation frequency. The reason for this is that for a cover rubber with an evaluation frequency of less than 10 kHz, that is, a cover rubber with a low impact speed in the use environment, there is little demand for impact performance and the need for evaluation using an impact performance evaluation index is also low. As stated in Fig. As illustrated in Figure 4, the value of the loss tangent tan δ increases with increasing frequency. However, using 10 kHz as a representative value for the evaluation frequency of the cover rubber requiring impact resistance performance, the impact resistance performance can be easily and accurately evaluated.

[0019] It should be noted that in the flowchart of Fig. 1 The evaluation frequency was determined after the main curve measurement with a loss tangent tan δ, but no such restriction is intended. The loss tangent tan δ of the frequency can be measured with pinpoint accuracy after the evaluation frequency has been determined. In addition, as described above, when the temperature characteristic is converted into a frequency characteristic, a temperature corresponding to the evaluation frequency can be calculated based on the relationship between the lines, and the loss tangent tan δ can be calculated by pinpointing the stress when vibration is applied to the rubber member at that temperature.

[0020] Finally, the elongation at break Eb, the tensile strength TSb and the loss tangent tan δ are used to evaluate the impact performance of the rubber element (step S16). In the present embodiment, a higher value for the impact performance index of the rubber member, that is, the product of the elongation at break Eb, the tear strength TSb, and the loss tangent tan δ of the rubber member, indicates high impact performance of the rubber member.

[0021] Fig. 5 is a table listing performance evaluation values ​​and performance evaluation test results of samples A to C. It should be noted that each Fig. 5 is an average of values ​​measured in a large number of samples of the same type. In Fig. 5, the evaluation frequency of the loss tangent tan δ is 10 kHz, and the value of sample A, which had the highest loss tangent tan δ, is set to a relative value of 100. For samples A, B, and C, the ultimate tensile strength TSb was 22.3, 28.2, and 20.9, respectively, the ultimate elongation Eb was 572, 562, and 530, respectively, and the relative value for the loss tangent tan δ was 100, 73, and 87, respectively. From these measurements, it can be seen that the relative values ​​for the impact performance evaluation index (Eb × TSb × tan δ) are 100, 90, 76 for Samples A, B, and C, respectively, and thus, when listed in order of highest impact performance, the samples are Sample A, Sample B, and Sample C.

[0022] In addition, as described above, the impact performances of the samples are compared using the relative values ​​for the impact performance evaluation index (Eb × TSb × tan δ), and the absolute values ​​for the impact performance evaluation index can be used to determine whether the sample meets a predetermined impact performance. Specifically, for example, in the case where the rubber member to be evaluated is a cover rubber covering a core body of a conveyor belt, when the impact performance evaluation index (Eb × TSb × tan δ) calculated using the loss tangent tan δ with the evaluation frequency equal to 10 kHz is, for example, 6,000 or greater, the impact performance is evaluated as high (satisfying the predetermined impact performance).

[0023] Fig. Figure 5 further lists the absolute values ​​for a fracture energy index (Eb × TSb) and the impact performance rating index (Eb × TSb × tan δ) of samples A, B and C. Fig. Figure 7 is a graph showing the impact performance evaluation index (Eb × TSb × tan δ) of samples A to C. The tan δ at each frequency (see Fig. 4) was multiplied by the fracture energy index (Eb × TSb) to obtain the graph of Fig. 7 to generate. As in Fig. 5, for samples A, B and C, the fracture energy index (Eb × TSb) is 12.761, 15.848 and 11.077, respectively, and the impact performance evaluation index (Eb × TSb × tan δ), in which the loss tangent tan δ at 10 kHz was multiplied by the fracture energy index (Eb × TSb), is 6.543, 5.901 and 4.944, respectively. Thus, only Sample A meets the criteria described above and has an impact performance rating index (Eb × TSb × tan δ) of 6,000 or greater.

[0024] The performance evaluation test was conducted by a drop impact test, a DIN abrasion test and a surface observation of the conveyor belt cover rubber after use for a predetermined period of time. The drop impact test was performed by dropping a needle from a predetermined height onto the surface of the specimen and measuring the penetration depth of the needle. The results were determined to be 17.2 mm and 19.9 mm for specimen A and B, respectively (the test was not performed on specimen C), indicating that specimen A was more resistant to drop impact than specimen B. The DIN abrasion test was conducted according to the method specified in JIS K6264-2, with the result being 122, 117, and 167 for Samples A, B, and C, respectively. Accordingly, Samples A and B exhibited high and approximately equal DIN abrasion resistance, and the DIN abrasion resistance of Sample C was lower than that of Samples A and B. Fig.Figures 6A to 6C are surface photographs of conveyor belt cover rubbers of Samples A to C made of the same materials after use for a predetermined period of time. Sample A exhibited very little cutting damage on the surface of the cover rubber. Sample B exhibited more cutting damage than Sample A, but had relatively little cutting damage. In contrast, Sample C exhibited a large amount of cutting damage.

[0025] From these results, it can be seen that the impact performance evaluation index (Eb × TSb × tan δ) using the elongation at break Eb, the tensile strength TSb and the loss tangent tan δ accurately reflects the impact performance of the actual rubber element.

[0026] As described above, the method for evaluating the impact resistance of a rubber member according to one embodiment includes evaluating the impact resistance performance of the rubber member using the elongation at break Eb, the tensile strength TSb, and the loss tangent tan δ of the rubber member, wherein the measurement condition of the loss tangent tan δ used in the impact resistance performance evaluation is determined based on the speed of the impact applied under use conditions of the rubber member. As a result, the impact resistance performance can be evaluated using the value of the loss tangent tan δ corresponding to an impact actually applied to the rubber member, and it is possible to improve the accuracy of the impact resistance performance evaluation.In addition, since the impact performance method for the rubber member according to an embodiment determines the measurement frequency (a predetermined frequency) of the loss tangent tan δ by adjusting the speed of impact applied under the use conditions of the rubber member to the maximum speed of vibrations, the impact performance can be evaluated by reflecting the viscosity of the rubber member which changes depending on the speed of impact. Furthermore, in the method for evaluating the impact resistance of a rubber member according to an embodiment, even in a case where the measurement of the loss tangent tan δ is performed at different temperatures instead of different frequencies, the value of the loss tangent tan δ corresponding to an impact actually applied when the rubber member is in use can be calculated. In addition, with the method for evaluating the impact resistance of a rubber member according to an embodiment, the elongation at break Eb, the tear strength TSb and the loss tangent tan δ can be easily unified and compared, and it is possible to provide an evaluation index that clearly reflects the impact resistance performance of the rubber member. Furthermore, such an evaluation index can clarify the development guidelines for impact-resistant rubber elements. A high loss tangent tan δ in a low frequency band leads to an increase in resistance to movement. Thus, for example, a rubber element with an improved loss tangent tan δ in a high frequency band can be developed according to the impact speed and the compressed loss tangent tan δ in a low frequency band. In this way, formulating development guidelines for rubber elements with selectively high cut resistance is advantageous.

Claims

[1] A method for evaluating the impact resistance of a rubber member, comprising the following step: Evaluating the impact performance of the rubber element using an elongation at break Eb, a tear strength TSb and a loss tangent tan δ of the rubber element; wherein a measurement condition of the loss tangent tan δ used in the step of evaluating the impact resistance performance is determined based on a speed of an impact applied under use conditions of the rubber member, wherein the loss tangent tan δ is a relationship between a storage modulus and a loss modulus calculated from a stress when vibrations of a predetermined frequency are applied to the rubber element; and the predetermined frequency of the measurement condition is determined by adjusting the speed of an impact exerted under conditions of use of the rubber element to a maximum speed of the vibrations, and wherein the rubber member is a cover rubber covering a belt core body of a conveyor belt and having the predetermined frequency of 10 kHz. [2] A method for evaluating the impact resistance of a rubber member according to claim 1, wherein a frequency characteristic curve showing a relationship between the loss tangent tan δ and a frequency of vibrations, and a temperature characteristic curve showing a relationship between the loss tangent tan δ and a temperature of the rubber element, are substitutable; and the loss tangent tan δ used in the step of evaluating the impact resistance performance is calculated by calculating the temperature corresponding to the predetermined frequency based on the relationship between the frequency characteristic and the temperature characteristic and using stress when vibration is applied to the rubber member at the temperature. [3] A method for evaluating the impact resistance of a rubber member according to claim 1 or 2, wherein an impact performance evaluation index of the rubber element is defined as a product of the elongation at break Eb, the tear strength TSb and the loss tangent tan δ of the rubber element, and when the impact performance calculated using the loss tangent tan δ at the predetermined frequency of 10 kHz is 6,000 or greater, the impact performance evaluation index is determined to be high. [4] A method for evaluating the impact resistance of a rubber member according to claim 3, wherein a higher value for the impact performance evaluation index of the rubber member indicates a high impact performance of the rubber member.

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