A method for testing the high-temperature activation energy of damping materials under the action of electric current and a method for predicting the creep mechanism

Abstract

The present invention discloses a method for testing the high-temperature activation energy of a damping material under the action of an electric current and a method for predicting the creep mechanism. The high-temperature activation energy testing method comprises: making a target damping material into a test sample of preset size specifications; mounting and fixing the test sample on a damping material test platform; using the damping material test platform to perform a damping test on the test sample under the action of an electric current to obtain the damping value of the test sample that changes with temperature at a certain current density and excitation frequency; and calculating the high-temperature activation energy of the damping material at a certain current density based on the damping value obtained from the test using a pre-constructed high-temperature activation energy calculation model for the damping material. The present invention can quantitatively describe the high-temperature activation energy of the damping material at a certain current density, temperature, and excitation frequency, and quickly predict the creep mechanism of the damping material under the action of an electric current at a certain current density. Therefore, the proposal of the present invention has certain scientific and engineering significance.

Description

Technical Field

[0001] The present invention relates to the field of high-temperature activation energy testing of damping materials, and in particular to a high-temperature activation energy testing method of damping materials under the action of electric current and a creep mechanism prediction method. Background Art

[0002] A material's damping (the ratio of its loss modulus to its storage modulus) is a key parameter determining its ability to dissipate vibration energy. The high-temperature activation energy of a damping material, to a certain extent, reflects the energy required for the damping material's microstructure to overcome potential barriers (grain boundary slip, dislocation proliferation, climb, etc.) and reach another equilibrium state. Microscopic changes in the damping material, such as grain boundary slip, dislocation proliferation, and climb, directly determine the damping material's ability to dissipate vibration energy. Creep activation energy refers to the thermal activation energy that controls the steady-state creep rate, and its value reflects the difficulty of the material's creep process. The same material exhibits different creep mechanisms and, consequently, different creep activation energies within different temperature and stress ranges. Therefore, accurate and effective testing and evaluation of the high-temperature activation energy and creep mechanisms of damping materials are of great significance.

[0003] Measuring the high-temperature activation energy of a damping material first requires measuring the damping value of the damping material as it changes with temperature and frequency, i.e., measuring the dynamic mechanical properties of the damping material. In practice, there are many methods for measuring the dynamic mechanical properties of damping materials, such as the forced resonance method, the bending resonance curve method, the torsion pendulum method, the wave propagation method, and the like. The present invention mainly utilizes the bending resonance method to perform damping testing. The bending resonance method is also called the cantilever beam method, and the loss factor of the damping material is mainly calculated from the resonance frequency and the resonance peak width. The damping of the damping material can vary greatly due to factors such as complex external environmental changes (strain amplitude, temperature, frequency, magnetic field, static load) and different measurement methods, among which the most important parameter affecting it is temperature.

[0004] Currently, measurements of the high-temperature activation energy of damping materials often rely on temperature and frequency as basic variables to quantitatively measure the high-temperature activation energy of damping materials. However, in reality, damping materials often operate in environments involving electric fields. Existing technologies lack the ability to measure the high-temperature activation energy of damping materials under the action of electric current, resulting in an inability to quantitatively measure this energy, significantly limiting the reliable assessment of the damping performance of damping materials. Furthermore, determining the creep mechanism by measuring the creep activation energy of damping materials in existing technologies often requires significant time and effort, resulting in low production efficiency.

[0005] Studies have shown that although the high-temperature activation energy and creep activation energy of damping materials are tested in different ways, there are great similarities in their microscopic changes, which makes it possible to predict the creep mechanism by testing the high-temperature activation energy of damping materials. Summary of the Invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art. In particular, it innovatively proposes a high-temperature activation energy testing method and a creep mechanism prediction method for damping materials under the action of electric current. The method can quantitatively describe the high-temperature activation energy of the damping material under a certain current density, temperature, and excitation frequency, and quickly predict the creep mechanism of the damping material under the action of electric current at a certain current density. The invention has certain scientific and engineering significance.

[0007] In order to achieve the above-mentioned object of the present invention, according to a first aspect of the present invention, the present invention provides a method for testing the high-temperature activation energy of a damping material under the action of an electric current, the method comprising:

[0008] The target damping material is made into a test sample with preset size specifications;

[0009] The sample to be tested is mounted and fixed on a damping material testing platform, wherein the damping material testing platform is used to test the damping value of the damping material under the action of electric current based on the bending resonance method, and the damping material testing platform includes a viscoelastic spectrometer and a current application device, and the current application device is used to apply electric current to the sample to be tested;

[0010] Using the damping material testing platform, a damping test is performed on the sample to be tested under the action of current to obtain a damping value of the sample to be tested that changes with temperature at a certain current density and excitation frequency;

[0011] Based on the damping value obtained by the test, the high-temperature activation energy of the damping material under a certain current density is calculated using a pre-constructed high-temperature activation energy calculation model for the damping material.

[0012] Preferably, the method further comprises the steps of:

[0013] A high-temperature activation energy calculation model for the damping material is constructed, wherein the high-temperature activation energy calculation model is as follows:

[0014]

[0015] Among them, Q -1 (T) represents the damping value obtained from the test, represents the loss factor under adiabatic background (loss factor value at -100℃ and 10Hz), H is the high temperature activation energy, ω is the angular frequency, n and K are material constants, k is the Boltzmann constant, and T is the temperature, where

[0016] ω=2πf Formula (2)

[0017] Where f is the excitation frequency.

[0018] Preferably, the high-temperature activation energy of the damping material under a certain current density is calculated based on the damping value obtained by the test using a pre-established high-temperature activation energy calculation model for the damping material, and includes:

[0019] Taking the logarithm of both sides of formula (1) yields the following formula:

[0020]

[0021] According to the damping value obtained by the test, the equation (3) is plotted. Curve and curve;

[0022] right The material constant n at a certain current density is obtained by linear fitting of the curve;

[0023] right The high-temperature activation energy H of the damping material under a certain current density is obtained by linear fitting of the curve.

[0024] Preferably, the viscoelastic spectrometer comprises a temperature-controlled heating furnace, a computer, an exciter, a cantilever beam fixed fixture and a cantilever beam movable fixture;

[0025] The cantilever beam fixed fixture and the cantilever beam movable fixture are both arranged in the furnace of the temperature-controlled heating furnace, two cantilever beam fixed fixtures are provided at intervals, the two cantilever beam fixed fixtures are used to clamp and fix the two ends of the sample to be tested, the cantilever beam movable fixture is arranged between the two cantilever beam fixed fixtures, the cantilever beam movable fixture is connected to the exciter driving, and the cantilever beam movable fixture is used to clamp the middle part of the sample to be tested to excite the sample to be tested to vibrate under the drive of the exciter;

[0026] The clamping surfaces of the cantilever beam fixed fixture and the cantilever beam movable fixture for clamping the sample to be tested are both provided with an insulating film layer, so that the cantilever beam fixed fixture and the cantilever beam movable fixture can achieve insulation between the sample to be tested after clamping the sample to be tested;

[0027] The temperature-controlled heating furnace is provided with a thermocouple temperature control device, which is used to detect and control the furnace temperature of the temperature-controlled heating furnace;

[0028] The exciter and the thermocouple temperature control device are electrically connected to the computer respectively. The computer is used to collect the excitation frequency of the exciter and the furnace temperature detected by the thermocouple temperature control device, and calculate the damping value of the sample to be tested that changes with temperature under a certain current density and excitation frequency based on the collected information.

[0029] Preferably, the current application device includes a power supply, a first insulated wire, a second insulated wire, a first conductive copper sheet and a second conductive copper sheet, wherein:

[0030] The power supply is arranged outside the temperature-controlled heating furnace;

[0031] One end of the first insulated wire is connected to the positive / negative pole of the power supply, and the other end of the first insulated wire passes through the furnace wall of the temperature-controlled heating furnace and is connected to the first conductive copper sheet; one end of the second insulated wire is connected to the negative / positive pole of the power supply, and the other end of the second insulated wire passes through the furnace wall of the temperature-controlled heating furnace and is connected to the second conductive copper sheet.

[0032] Preferably, the damping material testing platform further comprises a protective gas tank, a cooling gas tank and a gas cooling accessory, wherein:

[0033] The protective gas tank is used to input protective gas into the furnace of the temperature-controlled heating furnace through a vent pipe;

[0034] The gas cooling accessory is installed on the cooling gas tank, and the gas cooling accessory is electrically connected to the computer. The gas cooling accessory is used to cool the furnace of the temperature-controlled heating furnace through the ventilation pipe using the cooling gas in the cooling gas tank under the control of the computer.

[0035] Preferably, the damping test of the sample to be tested under the action of current using the damping material testing platform includes:

[0036] The first conductive copper sheet is clamped between one end surface of the sample to be tested and the insulating film layer on one of the cantilever beam fixing fixtures, and the second conductive copper sheet is clamped between the other end surface of the sample to be tested and the insulating film layer on the other cantilever beam fixing fixture;

[0037] Detecting the electrical connection status among the power supply, the first insulated wire, the first conductive copper sheet, the sample to be tested, the second conductive copper sheet, and the second insulated wire, so that a conductive loop is formed among the power supply, the first insulated wire, the first conductive copper sheet, the sample to be tested, the second conductive copper sheet, and the second insulated wire;

[0038] Testing the insulation status between a conductive loop formed by the power supply, the first insulated wire, the first conductive copper sheet, the sample to be tested, the second conductive copper sheet, and the second insulated wire and the temperature-controlled heating furnace, the cantilever beam fixed fixture, and the cantilever beam movable fixture of the viscoelastic spectrometer, respectively, to ensure that the conductive loop is completely insulated from the temperature-controlled heating furnace, the cantilever beam fixed fixture, and the cantilever beam movable fixture of the viscoelastic spectrometer;

[0039] Inputting protective gas into the furnace of the temperature-controlled heating furnace through a protective gas tank to exhaust the air in the furnace of the temperature-controlled heating furnace;

[0040] Starting a power supply and a computer, and measuring the damping value of the sample to be tested as it changes with temperature at a certain current density and excitation frequency, wherein during the measurement process, the computer controls the furnace temperature of the temperature-controlled heating furnace through a thermocouple temperature control device and a gas cooling accessory according to a preset temperature control program;

[0041] The computer displays and saves the measured damping value.

[0042] According to a second aspect of the present invention, a method for predicting the creep mechanism of a damping material based on high-temperature activation energy is provided, the method comprising the following steps:

[0043] The high-temperature activation energy of the damping material under a certain current density of the sample to be tested is obtained by testing the high-temperature activation energy of the damping material under the action of current according to any one of the above-mentioned first aspects;

[0044] Establishing a first correspondence table between current density and high-temperature activation energy based on the test results;

[0045] Obtaining a second corresponding relationship table of creep activation energy and stress index of the damping material corresponding to the sample to be tested under corresponding conditions;

[0046] Comparing and analyzing the high-temperature activation energy in the first correspondence table and the creep activation energy in the second correspondence table, and determining the creep activation energy corresponding to the high-temperature activation energy at a certain current density based on the comparative analysis results;

[0047] According to the determined creep activation energy, searching the second correspondence table for a stress index corresponding to the creep activation energy;

[0048] The creep mechanism of the damping material under the action of current of corresponding current density is predicted based on the stress index obtained by the search.

[0049] Preferably, the comparing and analyzing the high-temperature activation energy in the first correspondence table and the creep activation energy in the second correspondence table, and determining the creep activation energy corresponding to the high-temperature activation energy at a certain current density according to the comparative analysis results includes:

[0050] The high-temperature activation energy in the first correspondence table and the creep activation energy in the second correspondence table are compared and analyzed to determine that the creep activation energy in the second correspondence table that is equal to the high-temperature activation energy at a certain current density in the first correspondence table is the creep activation energy of the damping material corresponding to the sample to be tested at the current density.

[0051] Preferably, predicting the creep mechanism of the damping material under the action of a current of a corresponding current density according to the stress index obtained by searching includes:

[0052] The creep mechanism of the damping material under the action of the current of the corresponding current density is determined according to the corresponding relationship between the stress index obtained by the search and the preset stress index and the creep mechanism.

[0053] It can be seen from the above scheme that the present invention provides a method for testing the high-temperature activation energy of a damping material under the action of electric current. A damping test platform capable of applying electric current to a sample of the damping material to be tested is used to measure a large amount of data on the change of damping of the damping material with temperature and frequency under a certain current density. The obtained data is fitted and processed to calculate the high-temperature activation energy of the damping material under a certain current density and within a certain frequency range, thereby achieving a quantitative description of the high-temperature activation energy of the damping material under a certain current density, temperature, and excitation frequency, making up for the deficiency in the prior art that the high-temperature activation energy data of the damping material under the action of electric current cannot be quantitatively measured, and effectively improving the reliability of the evaluation of the high-temperature activation energy of the damping material.

[0054] In addition, the present invention also provides a method for predicting the creep mechanism of damping materials based on high-temperature activation energy. By analyzing and comparing the high-temperature activation energy of the damping material obtained from the test under the action of electric current with the creep activation energy of the same type of damping material in the database, the creep mechanism of the damping material under certain conditions can be predicted as needed, thereby realizing a rapid prediction of the creep mechanism of the damping material under the action of electric current at a certain current density, thereby making up for the deficiency of the prior art in that it is time-consuming and inefficient to judge the creep mechanism by measuring the creep activation energy of the damping material.

[0055] The invention has certain scientific and engineering significance, and the application prospect of the method for testing the high-temperature activation energy of the damping material under the action of electric current is broad, the experimental method is simple, and the actual operation is easy to implement.

[0056] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments with reference to the following drawings, in which:

[0058] Figure 1 This is a flow chart of a method for testing high-temperature activation energy of a damping material under the action of electric current in one embodiment of the present invention;

[0059] Figure 21 is a schematic structural diagram of a damping material testing platform for measuring high-temperature activation energy of a damping material under the action of electric current in one embodiment of the present invention;

[0060] Figure 3 The Sn0.7Cu solder in one embodiment of the present invention is Curve fitting graph;

[0061] Figure 4 The Sn3.5Ag solder in one embodiment of the present invention is Curve fitting graph;

[0062] Figure 5 The Sn0.3Ag0.7Cu solder in one embodiment of the present invention is Curve fitting graph;

[0063] Figure 6 The Sn0.7Cu solder in one embodiment of the present invention is Curve fitting graph;

[0064] Figure 7 The Sn3.5Ag solder in one embodiment of the present invention is Curve fitting graph;

[0065] Figure 8 The Sn0.3Ag0.7Cu solder in one embodiment of the present invention is Curve fitting graph;

[0066] Figure 9 This is a flow chart of a method for predicting creep mechanism of damping materials based on high temperature activation energy in one embodiment of the present invention. DETAILED DESCRIPTION

[0067] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0068] Those skilled in the art will understand that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art in the art to which the present invention pertains. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with those in the context of the prior art and, unless specifically defined, will not be interpreted in an idealized or overly formal sense.

[0069] like Figure 1As shown, an embodiment of the present invention provides a method for testing the high-temperature activation energy of a damping material under the action of an electric current. The method may include the following steps:

[0070] S101, preparing a target damping material into a test sample with preset size specifications;

[0071] When testing the high-temperature activation energy of a damping material under the action of an electric current or predicting its creep mechanism, the target damping material must first be fabricated into a test sample of predetermined dimensions. This can be done through mechanical cutting or chemical etching, with the dimensions of the test sample determined based on the experimental requirements.

[0072] It should be noted that the damping material mentioned in the present invention is a conductive viscoelastic material, including metals, conductive polymer materials, conductive ceramics and conductive composite materials.

[0073] S102, install and fix the sample to be tested on the damping material test platform (the structure of the damping material test platform is as follows Figure 2 As shown), wherein the damping material testing platform is used to test the damping value of the damping material under the action of current based on the bending resonance method, and the damping material testing platform includes a viscoelastic spectrometer 1 and a current application device 2, and the current application device 2 is used to apply current to the sample to be tested 100;

[0074] After the test sample 100 is prepared, the test sample 100 is mounted and fixed on the damping material test platform. Figure 2 As shown, the damping material testing platform includes a viscoelastic spectrometer 1 and a current application device 2 , and the current application device 2 is used to apply current to the sample 100 to be tested.

[0075] S103, performing a damping test on the sample under the action of current using a damping material test platform to obtain a damping value of the sample under the action of current density and excitation frequency as it changes with temperature;

[0076] Next, a damping test under current is performed on the sample 100 using a damping material test platform based on a bending resonance method, thereby obtaining a damping value of the sample 100 that varies with temperature at a certain current density and excitation frequency.

[0077] S104 , based on the damping value obtained from the test, a high-temperature activation energy of the damping material under a certain current density is calculated using a pre-established high-temperature activation energy calculation model for the damping material.

[0078] Finally, the damping value of the test sample 100 obtained by the test that changes with temperature at a certain current density and excitation frequency is used as the input parameter input value to the pre-built high-temperature activation energy calculation model for high-temperature activation energy calculation, and the high-temperature activation energy of the damping material at a certain current density can be obtained.

[0079] Specifically, in this embodiment, the current density ranges from 0 to 240 A / cm 2 .

[0080] In one embodiment, the method for testing the high-temperature activation energy of a damping material under the action of electric current further comprises the following steps:

[0081] A high-temperature activation energy calculation model for damping materials is constructed, wherein the high-temperature activation energy calculation model is as follows:

[0082]

[0083] Among them, Q -1 (T) represents the damping value obtained from the test, represents the loss factor under adiabatic background (loss factor value at -100℃ and 10Hz), H is the high temperature activation energy, ω is the angular frequency, n and K are material constants, k is the Boltzmann constant, and T is the temperature, where

[0084] ω=2πf Formula (2)

[0085] Where f is the excitation frequency.

[0086] In one embodiment, the high-temperature activation energy of the damping material under a certain current density is calculated based on the damping value obtained by the test using a pre-established high-temperature activation energy calculation model of the damping material, and includes:

[0087] Taking the logarithm of both sides of formula (1) yields the following formula:

[0088]

[0089] According to the damping value obtained from the test, the equation (3) is plotted. Curve and curve;

[0090] right The material constant n at a certain current density is obtained by linear fitting of the curve;

[0091] right The high-temperature activation energy H of the damping material under a certain current density is obtained by linear fitting of the curve.

[0092] Specifically, Curve and The linear fitting of the curve can be realized by using software such as Matlab or Origin. The linear fitting of the curve by using software such as Matlab or Origin belongs to the prior art and will not be described in detail here.

[0093] In one embodiment, Figure 2 As shown, the viscoelastic spectrometer 1 includes a temperature-controlled heating furnace 11, a computer 12, an exciter 13, a cantilever beam fixing fixture 14 and a cantilever beam movable fixture 15;

[0094] The cantilever beam fixed fixture 14 and the cantilever beam movable fixture 15 are both arranged in the furnace 111 of the temperature-controlled heating furnace 11. Two cantilever beam fixed fixtures 14 are provided at intervals. The two cantilever beam fixed fixtures 14 are used to clamp and fix the two ends of the sample 100 to be tested. The cantilever beam movable fixture 15 is arranged between the two cantilever beam fixed fixtures 14. The cantilever beam movable fixture 15 is driven and connected to the exciter 13. The cantilever beam movable fixture 15 is used to clamp the middle part of the sample 100 to be tested so as to excite the sample 100 to vibrate under the drive of the exciter 13.

[0095] The clamping surfaces of the cantilever beam fixed fixture 14 and the cantilever beam movable fixture 15 for clamping the sample 100 are both provided with an insulating film layer 16, so that the cantilever beam fixed fixture 14 and the cantilever beam movable fixture 15 can achieve insulation between the sample 100 after clamping the sample 100;

[0096] The temperature-controlled heating furnace 11 is provided with a thermocouple temperature control device (not shown in the figure), which is used to detect and control the temperature of the furnace 111 of the temperature-controlled heating furnace 11;

[0097] The exciter 13 and the thermocouple temperature control device are electrically connected to the computer 12 respectively. The computer 12 is used to collect the excitation frequency of the exciter 13 and the temperature of the furnace 111 detected by the thermocouple temperature control device, and calculate the damping value of the sample to be tested 100 as it changes with temperature under a certain current density and excitation frequency based on the collected information.

[0098] Specifically, in this embodiment, the insulating film layer 16 is a polyimide film, and the polyimide film is provided on the clamping surfaces of the cantilever beam fixing fixture 14 and the cantilever beam movable fixture 15 by bonding.

[0099] In one embodiment, Figure 2 As shown, the current application device 2 includes a power supply 21, a first insulated wire 22, a second insulated wire 23, a first conductive copper sheet 24 and a second conductive copper sheet 25, wherein:

[0100] The power supply 21 is provided outside the temperature-controlled heating furnace 11 and is used to provide direct current and / or alternating current of various waveforms, current magnitudes, and frequencies required for the test;

[0101] One end of the first insulated wire 22 is connected to the positive / negative pole of the power supply 21, and the other end of the first insulated wire 22 passes through the furnace wall of the temperature-controlled heating furnace 11 and is connected to the first conductive copper sheet 24; one end of the second insulated wire 23 is connected to the negative / positive pole of the power supply 21, and the other end of the second insulated wire 23 passes through the furnace wall of the temperature-controlled heating furnace 11 and is connected to the second conductive copper sheet 25.

[0102] In one embodiment, Figure 2 As shown, the damping material test platform also includes a protective gas tank 3, a cooling gas tank 4 and a gas cooling accessory 5, wherein,

[0103] The protective gas tank 3 is used to input protective gas into the furnace 111 of the temperature-controlled heating furnace 11 through the vent pipe;

[0104] The gas cooling accessory 5 is installed on the cooling gas tank 4, and the gas cooling accessory 5 is electrically connected to the computer 12. The gas cooling accessory 5 is used to cool the furnace 111 of the temperature-controlled heating furnace 11 through the ventilation pipe using the cooling gas in the cooling gas tank 4 under the control of the computer 12.

[0105] In one embodiment, the damping test of the sample 100 under the action of current using the damping material test platform includes:

[0106] The first conductive copper sheet 24 is sandwiched between one end surface of the sample 100 to be tested and the insulating film layer 16 on one of the cantilever beam fixing fixtures 14 , and the second conductive copper sheet 25 is sandwiched between the other end surface of the sample 100 to be tested and the insulating film layer 16 on the other cantilever beam fixing fixture 14 ;

[0107] Detect the electrical connection status between the power supply 21, the first insulated wire 22, the first conductive copper sheet 24, the sample 100 to be tested, the second conductive copper sheet 25, and the second insulated wire 23, so that a conductive loop is formed among the power supply 21, the first insulated wire 22, the first conductive copper sheet 24, the sample 100 to be tested, the second conductive copper sheet 25, and the second insulated wire 23;

[0108] Check the insulation status of the conductive loop formed by the power supply 21, the first insulated wire 22, the first conductive copper sheet 24, the sample to be tested 100, the second conductive copper sheet 25, and the second insulated wire 23, respectively, and the temperature-controlled heating furnace 11, the cantilever beam fixed fixture 14, and the cantilever beam movable fixture 15 of the viscoelastic spectrometer 1, so that the conductive loop and the temperature-controlled heating furnace 11, the cantilever beam fixed fixture 14, and the cantilever beam movable fixture 15 of the viscoelastic spectrometer 1 are completely insulated;

[0109] A protective gas is input into the furnace 111 of the temperature-controlled heating furnace 11 through the protective gas tank 3 to exhaust the air in the furnace 111 of the temperature-controlled heating furnace 11;

[0110] Start the power supply 21 and the computer 12 to measure the damping value of the sample 100 under a certain current density and excitation frequency as it changes with temperature. During the measurement, the computer 12 controls the temperature of the furnace 111 of the temperature-controlled heating furnace 11 through the thermocouple temperature control device and the gas cooling accessory 5 according to a preset temperature control program.

[0111] The computer 12 displays and saves the measured damping value.

[0112] The technical solution provided by the present invention can realize the test of high-temperature activation energy of damping materials under the action of electric current, and the experimental method is simple and the actual operation is easy to implement.

[0113] The following is a specific example to illustrate the technical solution of the method for testing the high temperature activation energy of damping materials under the action of current. The damping materials used in the high temperature activation energy test under the action of current in this specific example are lead-free solders Sn0.7Cu, Sn0.3Ag0.7Cu, and Sn3.5Ag, and the current density range of the current action is 0 to 240A / cm 2 The method for testing the high-temperature activation energy of the damping material under the action of the current includes the following steps:

[0114] Step 1: Select Sn0.7Cu, Sn3.5Ag, and Sn0.3Ag0.7Cu solders as test materials and mechanically cut them into test samples 100 with specifications of 60.0 mm×5.0 mm×1.0 mm.

[0115] Step 2, follow Figure 2 The structure shown is used to build a damping material test platform.

[0116] Step 3: A polyimide film is adhered and fixed as an insulating film layer 16 on the surface of the cantilever beam fixed fixture 14 and the cantilever beam movable fixture 15 to insulate the clamping surfaces of each fixture, and the sample to be tested 100 is placed on the cantilever beam fixed fixture 14 and the cantilever beam movable fixture 15 that have been insulated, and the sample to be tested 100 is fixed by adjusting the fixing bolts.

[0117] Step 4: Switch the multimeter to the on-off position, and use the red pen and black pen of the multimeter to touch the end of the first insulated wire 22 close to the power supply 21 and the end of the second insulated wire 23 close to the power supply 21 respectively to detect whether the conductive circuit formed by the first insulated wire 22, the sample to be tested 100, and the second insulated wire 23 is broken, so as to ensure that the conductive circuit formed by the first insulated wire 22, the sample to be tested 100, and the second copper wire is unobstructed; use the red pen of the multimeter to touch the end of the first insulated wire 22 or the second insulated wire 23 close to the power supply 21, and the black pen of the multimeter to touch the metal casing of the temperature-controlled heating furnace 11 to detect whether the conductive circuit formed by the power supply 21, the first insulated wire 22, the sample to be tested 100, and the second insulated wire 23 is completely insulated from the temperature-controlled heating furnace 11, the cantilever beam fixing fixture 14, and the cantilever beam movable fixture 15 of the viscoelastic spectrometer 1, so as to ensure that the above-mentioned conductive circuit is completely insulated from the temperature-controlled heating furnace 11, the cantilever beam fixing fixture 14, and the cantilever beam movable fixture 15 of the viscoelastic spectrometer 1.

[0118] Step 5: Inputting protective gas into the furnace 111 of the temperature-controlled heating furnace 11 through the protective gas tank 3 and exhausting the air in the temperature-controlled heating furnace 11.

[0119] In step 6, the computer 12 controls the viscoelastic spectrometer 1 to start the damping measurement program and simultaneously starts the power supply 21 to perform damping measurement on the sample 100 under the action of current. During the measurement process, the computer 12 controls the temperature of the furnace 111 of the temperature-controlled heating furnace 11 through the thermocouple temperature control device and the gas cooling accessories 5 (Gas Cooling Accessories, GCA for short). The computer 12 collects the damping value of the sample 100 under a certain current density and excitation frequency as it changes with temperature.

[0120] Step 7: The computer 12 uses the pre-built high-temperature activation energy calculation model of the damping material to perform curve drawing, linear fitting and other further analysis and processing on the damping value obtained from the test to obtain the high-temperature activation energy of the damping material under a certain current density. The test calculation results are shown in Table 1.

[0121] Table 1: Material constants n and high temperature activation energies H corresponding to various current densities of the test samples 100 of various damping materials obtained by test calculation

[0122]

[0123] The data in the first column of Table 1 correspond to current density values. Current density is equal to the amount of electricity passing through a unit area per unit time. Since the cross-sectional area of ​​the sample 100 to be tested is fixed, the current value, which is positively correlated with the current density, is used in Table 1 to represent the corresponding current density.

[0124] Specifically, in this embodiment, the curve fitting diagram of the test sample 100 of the damping material such as lead-free solder Sn0.7Cu, Sn0.3Ag0.7Cu, Sn3.5Ag in step 7 is as follows: Figure 3-8 shown.

[0125] In summary, the high-temperature activation energy testing method of a damping material under the action of electric current disclosed in the embodiment of the present invention measures a large amount of data on the change of damping of the damping material with temperature and frequency under a certain current density through a damping test platform that can apply current to the test sample 100 of the damping material, and fits the obtained data to calculate the high-temperature activation energy of the damping material under a certain current density and within a certain frequency range, thereby achieving a quantitative description of the high-temperature activation energy of the damping material under a certain current density, temperature, and excitation frequency, making up for the deficiency in the prior art that the high-temperature activation energy data of the damping material under the action of electric current cannot be quantitatively measured, and effectively improving the reliability of the evaluation of the high-temperature activation energy of the damping material.

[0126] Studies have shown that although the high-temperature activation energy and creep activation energy of damping materials are tested in different ways, there are great similarities in their microscopic changes. Based on the corresponding relationship between high-temperature activation energy and creep activation energy, the present invention also innovatively provides a method for predicting the creep mechanism of damping materials based on high-temperature activation energy, so as to predict the creep mechanism of damping materials under certain conditions, thereby solving the problem of prediction in the existing technology. This prediction method can effectively make up for the shortcomings of the existing technology in predicting creep mechanisms, which is time-consuming and inefficient.

[0127] like Figure 9 As shown, this embodiment provides a method for predicting the creep mechanism of a damping material based on high-temperature activation energy. The method may include the following steps:

[0128] S201, testing the damping material under the action of current according to any one of the above embodiments to obtain the high-temperature activation energy of the damping material under a certain current density of the sample to be tested;

[0129] S202, establishing a first correspondence table between current density and high-temperature activation energy based on the test results;

[0130] In a specific example, a first correspondence table between current density and high-temperature activation energy established based on the test results is shown in Table 2 below.

[0131] Table 2: The first correspondence between the current density and high temperature activation energy H of the tested samples of Sn0.7Cu, Sn0.3Ag0.7Cu, Sn3.5Ag and other damping materials obtained from the test

[0132]

[0133] The data in the first column of Table 1 represent current density values. Current density is equal to the amount of electricity passing through a unit area per unit time. Since the cross-sectional area of ​​the test sample is fixed, Table 1 uses current values, which are positively correlated with current density, to represent the corresponding current density. n is the material constant corresponding to the current density of the test samples of different damping materials, obtained from testing and calculation.

[0134] S203, obtaining a second correspondence table of creep activation energy and stress index of the damping material corresponding to the sample to be tested under corresponding conditions;

[0135] S204, comparing and analyzing the high-temperature activation energy in the first correspondence table and the creep activation energy in the second correspondence table, and determining the creep activation energy corresponding to the high-temperature activation energy at a certain current density based on the comparative analysis results. The specific process is as follows:

[0136] The high-temperature activation energy in the first correspondence table and the creep activation energy in the second correspondence table are compared and analyzed to determine that the creep activation energy in the second correspondence table that is equal to the high-temperature activation energy at a certain current density in the first correspondence table is the creep activation energy of the damping material corresponding to the sample to be tested at the current density.

[0137] Specifically, in order to facilitate comparison, the first correspondence table and the second correspondence table can be combined into a high-temperature activation energy and creep activation energy comparison analysis table, as shown in Table 3 below.

[0138] Table 3: Comparative analysis of the high-temperature activation energy H of Sn3.5Ag solder corresponding to various current densities obtained from the test and the creep activation energy H and stress index of Sn3.5Ag solder under the corresponding conditions reported in existing literature

[0139]

[0140] S205, searching a second correspondence table for a stress index corresponding to the determined creep activation energy according to the determined creep activation energy;

[0141] S206, predicting the creep mechanism of the damping material under the action of a current of a corresponding current density based on the found stress index, the specific process is as follows:

[0142] The creep mechanism of the damping material under the action of the current of the corresponding current density is determined according to the corresponding relationship between the found stress index and the preset stress index and the creep mechanism.

[0143] Specifically, the corresponding relationship between the stress index and creep mechanism of each damping material is the content disclosed in the prior art. For example, the corresponding relationship between the stress index and creep mechanism of Sn3.5Ag solder is as follows:

[0144] Stress index: N<3 is the creep mechanism controlled by grain boundary sliding; 3≤N≤6 is the creep mechanism controlled by dislocation climb; N>6 is the creep mechanism controlled by lattice diffusion. Therefore, it can be predicted that Sn3.5Ag solder will have a creep mechanism controlled by lattice diffusion in the current density range of 0~240A / cm 2 The creep mechanism is controlled by dislocation climb.

[0145] From the above, it can be seen that the method for predicting the creep mechanism of damping materials based on high-temperature activation energy provided by the embodiment of the present invention analyzes and compares the high-temperature activation energy of the damping material obtained by testing under the action of electric current with the creep activation energy of the same type of damping material in the database. As needed, the creep mechanism of the damping material under certain conditions can be predicted, and the creep mechanism of the damping material under the action of electric current of a certain current density can be quickly predicted, which makes up for the shortcomings of the prior art of measuring the creep activation energy of the damping material to determine the creep mechanism, which is time-consuming and inefficient.

[0146] The present invention implements all or part of the process of the method for testing the high-temperature activation energy of damping materials under the action of electric current in the above-mentioned embodiment by means of hardware that executes computer program instructions. The computer program may be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of each of the above-mentioned method embodiments may be implemented. The computer program includes computer program code, which may be in source code form, object code form, executable file, or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal, and software distribution medium. It should be noted that the content of the computer-readable medium may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0147] Those skilled in the art will appreciate that although some embodiments herein include certain features included in other embodiments but not other features, combinations of features from different embodiments are intended to be within the scope of the present invention and to form different embodiments. For example, in the claims below, any of the claimed embodiments may be used in any combination.

[0148] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for testing the high-temperature activation energy of a damping material under the action of an electric current, characterized in that: The method comprises the following steps: The target damping material is made into a test sample with preset size specifications; The sample to be tested is mounted and fixed on a damping material testing platform, wherein the damping material testing platform is used to test the damping value of the damping material under the action of current based on the bending resonance method, and the damping material testing platform includes a viscoelastic spectrometer and a current application device, and the current application device is used to apply current to the sample to be tested; Using the damping material testing platform, a damping test is performed on the sample to be tested under the action of current to obtain a damping value of the sample to be tested that changes with temperature at a certain current density and excitation frequency; Based on the damping value obtained by the test, the high-temperature activation energy of the damping material under a certain current density is calculated using a pre-constructed high-temperature activation energy calculation model for the damping material.

2. The method for testing the high temperature activation energy of a damping material under the action of electric current according to claim 1, characterized in that: The method further comprises the steps of: A high-temperature activation energy calculation model for the damping material is constructed, wherein the high-temperature activation energy calculation model is as follows: Among them, Q -1 (T) represents the damping value obtained from the test, represents the loss factor under adiabatic background, the loss factor value at -100℃ and 10Hz, H is the high temperature activation energy, ω is the angular frequency, n and K are material constants, k is the Boltzmann constant, and T is the temperature, where ω=2πf Formula (2) Where f is the excitation frequency.

3. The method for testing the high temperature activation energy of a damping material under the action of electric current according to claim 2, characterized in that: The high-temperature activation energy of the damping material under a certain current density is calculated based on the damping value obtained by the test using a pre-established high-temperature activation energy calculation model for the damping material, and includes: Taking the logarithm of both sides of formula (1) yields the following formula: According to the damping value obtained by the test, the equation (3) is plotted. Curve and curve; right The material constant n at a certain current density is obtained by linear fitting of the curve; right The high-temperature activation energy H of the damping material under a certain current density is obtained by linear fitting of the curve.

4. The method for testing the high temperature activation energy of a damping material under the action of electric current according to any one of claims 1 to 3, characterized in that: The viscoelastic spectrometer comprises a temperature-controlled heating furnace, a computer, an exciter, a cantilever beam fixed fixture and a cantilever beam movable fixture; The cantilever beam fixed fixture and the cantilever beam movable fixture are both arranged in the furnace of the temperature-controlled heating furnace, two cantilever beam fixed fixtures are provided at intervals, the two cantilever beam fixed fixtures are used to clamp and fix the two ends of the sample to be tested, the cantilever beam movable fixture is arranged between the two cantilever beam fixed fixtures, the cantilever beam movable fixture is connected to the exciter driving, and the cantilever beam movable fixture is used to clamp the middle part of the sample to be tested to excite the sample to be tested to vibrate under the drive of the exciter; The clamping surfaces of the cantilever beam fixed fixture and the cantilever beam movable fixture for clamping the sample to be tested are both provided with an insulating film layer, so that the cantilever beam fixed fixture and the cantilever beam movable fixture can achieve insulation between the sample to be tested after clamping the sample to be tested; The temperature-controlled heating furnace is provided with a thermocouple temperature control device, which is used to detect and control the furnace temperature of the temperature-controlled heating furnace; The exciter and the thermocouple temperature control device are electrically connected to the computer respectively. The computer is used to collect the excitation frequency of the exciter and the furnace temperature detected by the thermocouple temperature control device, and calculate the damping value of the sample to be tested that changes with temperature under a certain current density and excitation frequency based on the collected information.

5. The method for testing the high temperature activation energy of a damping material under the action of electric current according to claim 4, characterized in that: The current application device includes a power supply, a first insulated wire, a second insulated wire, a first conductive copper sheet and a second conductive copper sheet, wherein: The power supply is arranged outside the temperature-controlled heating furnace; One end of the first insulated wire is connected to the positive / negative pole of the power supply, and the other end of the first insulated wire passes through the furnace wall of the temperature-controlled heating furnace and is connected to the first conductive copper sheet; one end of the second insulated wire is connected to the negative / positive pole of the power supply, and the other end of the second insulated wire passes through the furnace wall of the temperature-controlled heating furnace and is connected to the second conductive copper sheet.

6. The method for testing the high temperature activation energy of a damping material under the action of electric current according to claim 5, characterized in that: The damping material test platform also includes a protective gas tank, a cooling gas tank and a gas cooling accessory, wherein: The protective gas tank is used to input protective gas into the furnace of the temperature-controlled heating furnace through a vent pipe; The gas cooling accessory is installed on the cooling gas tank, and the gas cooling accessory is electrically connected to the computer. The gas cooling accessory is used to cool the furnace of the temperature-controlled heating furnace through the ventilation pipe using the cooling gas in the cooling gas tank under the control of the computer.

7. The method for testing the high temperature activation energy of a damping material under the action of electric current according to claim 6, characterized in that: The damping test of the sample to be tested under the action of current using the damping material test platform includes: The first conductive copper sheet is clamped between one end surface of the sample to be tested and the insulating film layer on one of the cantilever beam fixing fixtures, and the second conductive copper sheet is clamped between the other end surface of the sample to be tested and the insulating film layer on the other cantilever beam fixing fixture; Detecting the electrical connection status among the power supply, the first insulated wire, the first conductive copper sheet, the sample to be tested, the second conductive copper sheet, and the second insulated wire, so that a conductive loop is formed among the power supply, the first insulated wire, the first conductive copper sheet, the sample to be tested, the second conductive copper sheet, and the second insulated wire; Testing the insulation status between a conductive loop formed by the power supply, the first insulated wire, the first conductive copper sheet, the sample to be tested, the second conductive copper sheet, and the second insulated wire and the temperature-controlled heating furnace, the cantilever beam fixed fixture, and the cantilever beam movable fixture of the viscoelastic spectrometer, respectively, to ensure that the conductive loop is completely insulated from the temperature-controlled heating furnace, the cantilever beam fixed fixture, and the cantilever beam movable fixture of the viscoelastic spectrometer; Inputting protective gas into the furnace of the temperature-controlled heating furnace through a protective gas tank to exhaust the air in the furnace of the temperature-controlled heating furnace; Starting a power supply and a computer, and measuring the damping value of the sample to be tested as it changes with temperature at a certain current density and excitation frequency, wherein during the measurement process, the computer controls the furnace temperature of the temperature-controlled heating furnace through a thermocouple temperature control device and a gas cooling accessory according to a preset temperature control program; The computer displays and saves the measured damping value.

8. A method for predicting creep mechanism of damping materials based on high temperature activation energy, characterized in that: The steps include: The high-temperature activation energy of the damping material under a certain current density is obtained by testing according to the high-temperature activation energy testing method of the damping material under the action of current according to any one of claims 1 to 7; Establishing a first correspondence table between current density and high-temperature activation energy based on the test results; Obtaining a second corresponding relationship table of creep activation energy and stress index of the damping material corresponding to the sample to be tested under corresponding conditions; Comparing and analyzing the high-temperature activation energy in the first correspondence table and the creep activation energy in the second correspondence table, and determining the creep activation energy corresponding to the high-temperature activation energy at a certain current density based on the comparative analysis results; According to the determined creep activation energy, searching the second correspondence table for a stress index corresponding to the creep activation energy; The creep mechanism of the damping material under the action of current of corresponding current density is predicted based on the stress index obtained by the search.

9. The method for predicting creep mechanism of damping materials based on high temperature activation energy according to claim 8, characterized in that: The comparing and analyzing the high-temperature activation energy in the first correspondence table and the creep activation energy in the second correspondence table, and determining the creep activation energy corresponding to the high-temperature activation energy at a certain current density according to the comparison and analysis results includes: The high-temperature activation energy in the first correspondence table and the creep activation energy in the second correspondence table are compared and analyzed to determine that the creep activation energy in the second correspondence table that is equal to the high-temperature activation energy at a certain current density in the first correspondence table is the creep activation energy of the damping material corresponding to the sample to be tested at the current density.

10. The method for predicting creep mechanism of damping materials based on high temperature activation energy according to claim 9, characterized in that: The method of predicting the creep mechanism of the damping material under the action of a current of a corresponding current density according to the stress index obtained by searching includes: The creep mechanism of the damping material under the action of the current of the corresponding current density is determined according to the corresponding relationship between the stress index obtained by the search and the preset stress index and the creep mechanism.

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