Method and device for calculating environmental coefficient of electronic component in preset temperature vibration environment

Abstract

The invention provides an environment coefficient calculation method and device of an electronic component in a preset temperature vibration environment. The method comprises the following steps: constructing a finite element model according to structural parameters of a to-be-predicted component; performing temperature cycle simulation on the finite element model, and calculating temperature cycle damage according to a temperature cycle simulation result and a Muno Miner law; performing random vibration simulation on the finite element model by taking a preset temperature cycle condition as prestress, and calculating random vibration damage according to a random vibration simulation result and a Miner law; the temperature cycle damage and the random vibration damage are subjected to damage superposition, and the total life of the to-be-predicted component is calculated according to the damage superposition result and the Miner law; based on the total life and the electronic equipment reliability prediction manual, the influence of packaging factors in the failure rate is removed, the environment coefficient of the to-be-predicted component under the preset temperature cycle condition is obtained, and the accuracy and reliability of failure rate prediction of the electronic component are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic equipment reliability evaluation and prediction, and in particular to a method and device for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment. Background Art

[0002] In the field of electronic equipment reliability assessment, accurate prediction of the failure rate of electronic components is crucial to ensure the long-term stable operation of the equipment. Since its launch in 2006, GJB / Z 299C-2006 "Handbook of Reliability Prediction of Electronic Equipment" has been the authoritative standard in this field and is widely used in the prediction of failure rates of electronic components. The handbook comprehensively considers internal and external failure factors, and introduces quality coefficients and maturity coefficients as adjustment factors to construct a relatively complete failure rate prediction system, providing strong support for engineering practice.

[0003] In current engineering practice, GJB / Z 299C-2006 "Handbook of Reliability Prediction of Electronic Equipment" is still the main reference for the prediction of failure rate of electronic components. This handbook not only takes into account the internal and external failure mechanisms of the device, but also further improves the practicality and universality of the prediction model by introducing adjustment factors such as quality coefficient and maturity coefficient. This standard has accumulated rich practical experience and data support in many years of application, providing a reliable basis for the reliability evaluation of electronic components. However, with the continuous advancement of technology, the requirements for prediction accuracy are also constantly increasing, which makes the application of this handbook under certain specific conditions challenged.

[0004] Although GJB / Z 299C-2006 "Handbook of Reliability Prediction of Electronic Equipment" has played an important role in the prediction of failure rate of electronic components, it was published at an early time, and the experimental data and technical background it was based on are quite different from the actual application environment of modern electronic components. In particular, in the setting of environmental coefficients, the manual only provides relatively general environmental classifications such as general ground fixation, violent ground movement, and missile flight, and lacks an accurate quantitative description of environmental loads. This general environmental classification is often difficult to accurately reflect the actual stress conditions of electronic components when faced with modern complex and diverse loading conditions, resulting in large errors in the prediction results. Therefore, how to overcome the limitations of the existing manual in setting environmental coefficients and improve the accuracy and reliability of electronic component failure rate prediction has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a method and device for calculating the environmental coefficient of electronic components in a preset temperature and vibration environment.

[0006] The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0007] In a first aspect, the present invention provides a method for calculating the environmental coefficient of an electronic component in a preset temperature and vibration environment, comprising:

[0008] Construct a finite element model according to the structural parameters of the components to be predicted;

[0009] Perform temperature cycle simulation on the finite element model and calculate the temperature cycle damage based on the results of temperature cycle simulation and Manno-Miner's law;

[0010] The finite element model is subjected to random vibration simulation using the preset temperature cycle conditions as prestress, and the random vibration damage is calculated based on the random vibration simulation results and Miner's law;

[0011] The temperature cycle damage and random vibration damage are superimposed, and the total life of the components to be predicted is calculated based on the damage superposition results and Miner's law;

[0012] Based on the total life and electronic equipment reliability prediction handbook, the influence of packaging factors in the failure rate is removed to obtain the environmental coefficient of the components to be predicted under the preset temperature cycle conditions.

[0013] Optionally, a temperature cycle simulation is performed on the finite element model, and the temperature cycle damage is calculated according to the results of the temperature cycle simulation and Miner's law, including:

[0014] The finite element model is simulated by temperature cycle to obtain the shear plastic strain curve;

[0015] Based on the shear plastic strain curve and the modified Manson-Coffin formula, the temperature cycle life of the component to be predicted is calculated;

[0016] According to Miner's law, the inverse of the temperature cycle life is calculated to obtain the temperature cycle damage.

[0017] Optionally, a random vibration simulation is performed on the finite element model using a preset temperature cycle condition as a prestress, and the random vibration damage is calculated according to the result of the random vibration simulation and Miner's law, including:

[0018] Using the preset temperature cycle conditions as prestress input in the preset simulation application, the resonance frequency and elastic strain range corresponding to the finite element model are obtained;

[0019] Substitute the resonance frequency into the positive zero passing number formula to calculate the positive zero passing number value;

[0020] The number of fatigue cycles is calculated based on the elastic strain range;

[0021] Random vibration calculation is performed based on Miner's law, the number of positive zero passes and the number of fatigue cycles to obtain random vibration damage.

[0022] Alternatively, the positive zero pass number formula is expressed as:

[0023]

[0024] in, represents the number of positive zero passing times, m represents the total order of the resonant frequency, P i represents the acceleration power spectrum density value corresponding to the i-th order resonance frequency, f i represents the i-th order resonant frequency value, Q i represents the transmission rate obtained by the i-th order resonant frequency, Ω i represents the i-th order natural circular frequency.

[0025] Alternatively, the relationship between the elastic strain range and the number of fatigue cycles is expressed as:

[0026]

[0027] Δε iσ represents the elastic strain range of random vibration excitation in the iσ interval, σ u represents the tensile strength of the component to be predicted, E represents the elastic modulus, N iσ represents the number of fatigue cycles of random vibration excitation in the iσ interval, and σ is the variance of the normal distribution of random vibration excitation.

[0028] Alternatively, the formula for random vibration calculation is expressed as:

[0029]

[0030] Among them, D V represents the random vibration damage, represents the number of positive zero passes, N 1σ 、N 2σ and N 3σ It corresponds to the number of fatigue cycles of random vibration excitation in the intervals of 1σ, 2σ and 3σ, and σ is the variance of the normal distribution of random vibration excitation.

[0031] Optionally, the temperature cycle damage and random vibration damage are superimposed, and the total life of the component to be predicted is calculated based on the damage superposition result and Miner's law, including:

[0032] According to the preset weighted ratio, the temperature cycle damage and random vibration damage are summed to obtain the total damage of the components to be predicted;

[0033] Take the inverse of the total damage to obtain the total life of the component to be predicted.

[0034] Optionally, based on the total life and the electronic equipment reliability prediction handbook, the influence of the packaging factor in the failure rate is removed to obtain the environmental coefficient of the component to be predicted under the preset temperature cycle conditions, including:

[0035] The failure rate λ of the component to be predicted is calculated based on the total life and the first preset formula;

[0036] By looking up the table in the Electronic Equipment Reliability Prediction Handbook, the packaging complexity failure rate C3 of the components to be predicted is obtained;

[0037] Using the second preset formula, the failure rate λ and the packaging complexity failure rate C3, an environmental coefficient is obtained;

[0038] Among them, the first preset formula is expressed as: N represents the total life span;

[0039] The second preset formula is expressed as: C3 represents the packaging complexity failure rate, π E Indicates the environmental factor.

[0040] In a second aspect, the present invention provides an environmental coefficient calculation device for electronic components under a preset temperature and vibration environment, the environmental coefficient calculation device for electronic components under a preset temperature and vibration environment comprises: a model building unit, a temperature simulation unit, a vibration simulation unit and a calculation unit;

[0041] The model building unit is used to: build a finite element model according to the structural parameters of the components to be predicted;

[0042] The temperature simulation unit is used to: perform temperature cycle simulation on the finite element model and calculate the temperature cycle damage based on the results of the temperature cycle simulation and Miner's law;

[0043] The vibration simulation unit is used to: perform random vibration simulation on the finite element model using the preset temperature cycle conditions as prestress, and calculate the random vibration damage based on the results of the random vibration simulation and Miner's law;

[0044] The calculation unit is used to: superimpose the temperature cycle damage and the random vibration damage, and calculate the total life of the components to be predicted based on the damage superposition result and Miner's law;

[0045] The calculation unit is also used to obtain the environmental coefficient of the component to be predicted under the preset temperature cycle conditions based on the total life and the electronic equipment reliability prediction manual.

[0046] In a third aspect, the present invention provides an environmental coefficient calculation device for electronic components in a preset temperature and vibration environment, comprising: a processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor. When the environmental coefficient calculation device is running, the processor and the storage medium communicate through the bus, and the processor executes the machine-readable instructions to perform the steps of any environmental coefficient calculation method as described in the first aspect above.

[0047] The present invention provides a method and device for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment. Among them, a method for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment includes: constructing a finite element model according to the structural parameters of the components to be predicted; performing temperature cycle simulation on the finite element model, and calculating the temperature cycle damage according to the results of the temperature cycle simulation and the Manno-Miner law; performing random vibration simulation on the finite element model with the preset temperature cycle conditions as prestress, and calculating the random vibration damage according to the results of the random vibration simulation and the Miner law; superimposing the temperature cycle damage and the random vibration damage, and calculating the total life of the components to be predicted according to the results of the damage superposition and the Miner law; based on the total life and the electronic equipment reliability prediction manual, removing the influence of the packaging factor in the failure rate, and obtaining the environmental coefficient of the components to be predicted under the preset temperature cycle conditions. In the present invention, by constructing a finite element model and performing temperature cycle simulation and random vibration simulation, the stress and strain conditions of electronic components in a preset temperature and vibration environment can be more accurately reflected, thereby improving the accuracy of failure rate prediction; by superimposing temperature cycle damage and random vibration damage to obtain total damage, and calculating the total life and failure rate based on this, the reliability of electronic components under complex loading conditions can be more comprehensively considered; finally, the influence of packaging factors is eliminated, and the environmental coefficient under the corresponding loading conditions is calculated, which provides more accurate data support for the reliability evaluation of electronic components. In summary, the method of the present invention improves the accuracy and reliability of electronic component failure rate prediction.

[0048] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 A schematic flow chart of a method for calculating an environmental coefficient of an electronic component in a preset temperature and vibration environment provided by an embodiment of the present invention;

[0050] Figure 2 A schematic diagram of the structure of an environmental coefficient calculation device for electronic components in a preset temperature and vibration environment provided by an embodiment of the present invention;

[0051] Figure 3 A schematic diagram of the structure of an environmental coefficient calculation device for electronic components in a preset temperature and vibration environment provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0052] The present invention is further described in detail below with reference to specific embodiments, but the embodiments of the present invention are not limited thereto.

[0053] In order to improve the accuracy and reliability of the prediction of the failure rate of electronic components, an embodiment of the present invention provides a method for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment. Figure 1 A schematic flow chart of a method for calculating an environmental coefficient of an electronic component in a preset temperature and vibration environment provided by an embodiment of the present invention.

[0054] As shown in the figure, it includes:

[0055] S101, constructing a finite element model according to the structural parameters of the components to be predicted.

[0056] Specifically, first, the structural parameters of the component to be predicted are obtained, including dimensions, material properties, and expected loads and boundary conditions; based on these parameters, an accurate 3D geometric model is built in SOLIDWORKS and the materials are specified. Then, the simulation environment is set up using the ANSYS Workbench module, the corresponding boundary conditions and loads are applied, and meshing is performed to prepare for calculations. Finally, a finite element analysis is run and the results are evaluated to obtain a finite element model that can be used to predict component behavior.

[0057] 102. Perform temperature cycle simulation on the finite element model and calculate the temperature cycle damage based on the results of temperature cycle simulation and Manno-Miner's law.

[0058] Optionally, S102 may specifically include:

[0059] The finite element model is simulated by temperature cycle to obtain the shear plastic strain curve;

[0060] Based on the shear plastic strain curve and the modified Manson-Coffin formula, the temperature cycle life of the component to be predicted is calculated;

[0061] According to Miner's law, the inverse of the temperature cycle life is calculated to obtain the temperature cycle damage.

[0062] In this embodiment, the temperature cycle damage is the temperature cycle damage accumulated per cycle. The specific logic of temperature cycle simulation of the finite element model is: first, ensure that the material properties include temperature dependence and plastic behavior, and build or import a 3D model in ANSYS Workbench; then, set up thermal-mechanical analysis, apply temperature cycle loads and boundary conditions, perform meshing and configure solution parameters; finally, run the simulation, extract data and generate shear plastic strain curves through post-processing tools, and evaluate the performance of the component under temperature cycling based on this shear plastic strain curve. The modified Manson-Coffin formula is specifically the Engelmaier modified Coffin-Manson formula.

[0063] Furthermore, the temperature cycle simulation process can also be replaced by a life calculation method based on strain energy, creep, etc.

[0064] S103, performing random vibration simulation on the finite element model using a preset temperature cycle condition as a prestress, and calculating random vibration damage according to the random vibration simulation result and Miner's law.

[0065] Optionally, S103 may specifically include:

[0066] Using the preset temperature cycle conditions as prestress input in the preset simulation application, the resonance frequency and elastic strain range corresponding to the finite element model are obtained;

[0067] Substitute the resonance frequency into the positive zero passing number formula to calculate the positive zero passing number value;

[0068] The number of fatigue cycles is calculated based on the elastic strain range;

[0069] Random vibration calculation is performed based on Miner's law, the number of positive zero passes and the number of fatigue cycles to obtain random vibration damage.

[0070] It should be noted that, in this embodiment, the random vibration damage is specifically the random vibration damage accumulated per second.

[0071] In addition, the random vibration simulation process can also be replaced by life calculation methods such as rain flow counting method.

[0072] Alternatively, the positive zero pass number formula is expressed as:

[0073]

[0074] in, represents the number of positive zero passing times, m represents the total order of the resonant frequency, P i represents the acceleration power spectrum density value corresponding to the i-th order resonance frequency, f i represents the i-th order resonant frequency value, Qi represents the transmission rate obtained by the i-th order resonant frequency, Ω i represents the i-th order natural circular frequency.

[0075] Ω i =2πf i ;

[0076]

[0077] Among them, G i is the default number of gravity units, dimensionless.

[0078] In the embodiment of the present invention, the number of fatigue cycles is calculated using a Steinberg model based on normal distribution, which divides the random vibration excitation of the load into three intervals: (-1σ, +1σ), (-2σ, -1σ)∪(+1σ, +2σ) and (-3σ, -2σ)∪(+2σ, +3σ), and ignores random vibrations above 3σ. The probability of the instantaneous acceleration occurring in the three intervals is 68.3%, 27.1% and 4.33% respectively, and σ is the variance of the Gaussian normal distribution of the random vibration excitation.

[0079] The number of fatigue cycles corresponding to each interval excitation level is calculated by the Coffin-Manson formula considering only elastic strain:

[0080]

[0081] Δε iσ represents the elastic strain range of random vibration excitation in the iσ interval, σ u represents the tensile strength of the component to be predicted, E represents the elastic modulus, N iσ represents the number of fatigue cycles of random vibration excitation in the iσ interval, and σ is the variance of the normal distribution of random vibration excitation.

[0082] Alternatively, the formula for random vibration calculation is expressed as:

[0083]

[0084] Among them, D V represents the random vibration damage, N0 + represents the number of positive zero passes, N 1σ 、N 2σ and N 3σ It corresponds to the number of fatigue cycles of random vibration excitation in the intervals of 1σ, 2σ and 3σ, and σ is the variance of the normal distribution of random vibration excitation.

[0085] It should be noted that the preset simulation application is specifically ANSYS Workbench.

[0086] S104, superimposing the temperature cycle damage and the random vibration damage, and calculating the total life of the component to be predicted based on the damage superposition result and Miner's law.

[0087] Optionally, S104 may specifically include:

[0088] According to the preset weighted ratio, the temperature cycle damage and random vibration damage are summed to obtain the total damage of the components to be predicted;

[0089] Take the inverse of the total damage to obtain the total life of the component to be predicted.

[0090] It should be noted that the total damage is the total damage accumulated per hour of the components to be predicted.

[0091] In the embodiment of the present invention, the total damage is expressed as:

[0092] D total =A T D T +A V D V ;

[0093] Among them, D total Denotes the total damage accumulated per hour for the components to be predicted, D T Indicates temperature cycle damage, D V represents random vibration damage, A T represents the temperature cycle damage coefficient, A V Denotes the random vibration damage coefficient. Specifically, D T is the damage caused by each cycle of temperature cycling, D V The damage caused by random vibration per second.

[0094] In addition, the above process of calculating the total life of the components to be predicted in S101-S104 can also be obtained by performing destructive tests on a large number of sample components and then fitting the experimental results.

[0095] S105. Based on the total life and the electronic equipment reliability prediction handbook, remove the influence of packaging factors in the failure rate and obtain the environmental coefficient of the component to be predicted under the preset temperature cycle conditions.

[0096] Optionally, S105 may specifically include:

[0097] The failure rate λ of the component to be predicted is calculated based on the total life and the first preset formula;

[0098] By looking up the table in the Electronic Equipment Reliability Prediction Handbook, the packaging complexity failure rate C3 of the components to be predicted is obtained;

[0099] Using the second preset formula, the failure rate λ and the packaging complexity failure rate C3, an environmental coefficient is obtained;

[0100] Among them, the first preset formula is expressed as: N represents the total lifespan, the unit of total lifespan is hour h, and the unit of failure rate λ is h -1 .

[0101] In the embodiment of the present invention, after the failure rate λ is calculated, since solder is the main danger point of the device under temperature and vibration conditions, the failure rate can be regarded as the packaging failure rate of the device. According to the Electronic Equipment Reliability Prediction Handbook GJB / Z299C-2006, the packaging failure rate can be calculated by multiplying the packaging complexity failure rate C3 by the environmental factor π E So the environmental coefficient π under the corresponding loading condition is E It can be calculated by the following second preset formula:

[0102] The second preset formula is expressed as: C3 represents the packaging complexity failure rate, π E Indicates the environmental factor.

[0103] In summary, the present invention obtains the environmental coefficient under specific temperature cycle and random vibration coupling loading conditions through finite element analysis, which solves the problem that the general environmental classification in GJB / Z 299C-2006 "Handbook of Reliability Prediction of Electronic Equipment" will have large errors when facing today's complex and diverse loading conditions. In addition, the method of the present invention provides a method for calculating the environmental coefficient only related to the loading conditions based on the reliability model in GJB / Z299C-2006 "Handbook of Reliability Prediction of Electronic Equipment". The environmental coefficient calculated by this method can be directly used in the reliability prediction of other devices under the same loading conditions in the future, thereby improving the accuracy and efficiency of reliability prediction.

[0104] An embodiment of the present invention provides a method for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment, including: constructing a finite element model according to the structural parameters of the components to be predicted; performing temperature cycle simulation on the finite element model, and calculating the temperature cycle damage according to the results of the temperature cycle simulation and Manno Miner's law; performing random vibration simulation on the finite element model with preset temperature cycle conditions as prestress, and calculating the random vibration damage according to the results of the random vibration simulation and Miner's law; superimposing the temperature cycle damage and the random vibration damage, and calculating the total life of the components to be predicted according to the results of the damage superposition and Miner's law; based on the total life and the Handbook of Reliability Prediction of Electronic Equipment, removing the influence of packaging factors in the failure rate, and obtaining the environmental coefficient of the components to be predicted under preset temperature cycle conditions. In an embodiment of the present invention, by constructing a finite element model and performing temperature cycle simulation and random vibration simulation, the stress and strain conditions of electronic components in a preset temperature and vibration environment can be more accurately reflected, thereby improving the accuracy of failure rate prediction; by superimposing temperature cycle damage and random vibration damage to obtain total damage, and calculating the total life and failure rate based on this, the reliability of electronic components under complex loading conditions can be more comprehensively considered; finally, the influence of packaging factors is eliminated, and the environmental coefficient under the corresponding loading conditions is calculated, which provides more accurate data support for the reliability evaluation of electronic components. In summary, the method of the present invention improves the accuracy and reliability of electronic component failure rate prediction.

[0105] The method provided in the embodiment of the present invention can be applied to an electronic device. Specifically, the electronic device can be: a desktop computer, a portable computer, an intelligent mobile terminal, a server, etc., which is not limited in the embodiment of the present invention.

[0106] Based on the same inventive concept, an embodiment of the present invention further provides a device for calculating an environmental coefficient of an electronic component under a preset temperature and vibration environment. Figure 2 A schematic diagram of the structure of an environmental coefficient calculation device for electronic components in a preset temperature and vibration environment provided by an embodiment of the present invention. Figure 2 As shown, it includes: a model building unit 201, a temperature simulation unit 202, a vibration simulation unit 203 and a calculation unit 204;

[0107] The model building unit 201 is used to: build a finite element model according to the structural parameters of the components to be predicted;

[0108] The temperature simulation unit 202 is used to: perform temperature cycle simulation on the finite element model, and calculate the temperature cycle damage according to the results of the temperature cycle simulation and Miner's law;

[0109] The vibration simulation unit 203 is used to: perform random vibration simulation on the finite element model using a preset temperature cycle condition as a prestress, and calculate random vibration damage according to the result of the random vibration simulation and Miner's law;

[0110] The calculation unit 204 is used to: perform damage superposition on the temperature cycle damage and the random vibration damage, and calculate the total life of the component to be predicted according to the damage superposition result and Miner's law;

[0111] The calculation unit 204 is further used to obtain the environmental coefficient of the component to be predicted under the preset temperature cycle conditions based on the total life and the electronic equipment reliability prediction manual.

[0112] Figure 3 A schematic diagram of the structure of an environmental coefficient calculation device for an electronic component in a preset temperature and vibration environment provided by an embodiment of the present invention includes: a processor 310, a storage medium 320 and a bus 330, wherein the storage medium 320 stores machine-readable instructions executable by the processor 310, and when the environmental coefficient calculation device for an electronic component in a preset temperature and vibration environment is running, the processor 310 communicates with the storage medium 320 via the bus 330, and the processor 310 executes the machine-readable instructions to execute the steps of the above method embodiment. The specific implementation method and technical effect are similar and will not be repeated here.

[0113] The storage medium may include a random access memory (RAM) or a non-volatile memory (NVM), such as at least one disk storage. Optionally, the storage medium may also be at least one storage device located away from the aforementioned processor.

[0114] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0115] It should be noted that the terms "first", "second", etc. are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention.

[0116] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0117] Although the present invention is described herein in conjunction with various embodiments, in the process of implementing the claimed invention, those skilled in the art can understand and implement other changes of the above disclosed embodiments by viewing the drawings and the disclosed content. In the description of the present invention, the term "comprising" does not exclude other components or steps, "one" or "an" does not exclude multiple situations, and the meaning of "multiple" is two or more, unless otherwise clearly and specifically limited. In addition, certain measures are recorded in different embodiments, but this does not mean that these measures cannot be combined to produce good results.

[0118] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the scope of protection of the present invention.

Claims

1. A method for calculating the environmental coefficient of electronic components in a preset temperature and vibration environment, characterized in that: include: Construct a finite element model according to the structural parameters of the components to be predicted; Performing temperature cycle simulation on the finite element model, and calculating temperature cycle damage according to the result of the temperature cycle simulation and Manno-Miner's law; Performing random vibration simulation on the finite element model using a preset temperature cycle condition as a prestress, and calculating random vibration damage according to the result of the random vibration simulation and Miner's law; Superimposing the temperature cycle damage and the random vibration damage, and calculating the total life of the component to be predicted according to the result of the damage superposition and Miner's law; Based on the total life and the electronic equipment reliability prediction handbook, the influence of packaging factors in the failure rate is removed to obtain the environmental coefficient of the component to be predicted under preset temperature cycle conditions.

2. The method for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment according to claim 1, characterized in that: The performing of temperature cycle simulation on the finite element model and calculating the temperature cycle damage according to the result of the temperature cycle simulation and Miner's law include: Performing temperature cycle simulation on the finite element model to obtain a shear plastic strain curve; Based on the shear plastic strain curve and the modified Manson-Coffin formula, the temperature cycle life of the component to be predicted is calculated; The temperature cycle damage is obtained by calculating the inverse of the temperature cycle life according to the Miner's law.

3. The method for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment according to claim 1, characterized in that: The method of performing random vibration simulation on the finite element model using the preset temperature cycle condition as prestress, and calculating random vibration damage according to the result of the random vibration simulation and Miner's law, comprises: Using the preset temperature cycle condition as the prestress input into a preset simulation application, obtaining a resonance frequency and an elastic strain range corresponding to the finite element model; Substituting the resonant frequency into the positive zero passing number formula, the positive zero passing number value is calculated; Calculating the number of fatigue cycles based on the elastic strain range; The random vibration damage is obtained by performing random vibration calculation based on the Miner's law, the positive zero passage number value and the fatigue cycle number.

4. The method for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment according to claim 3, characterized in that: The positive zero passing number formula is expressed as: in, represents the number of positive zero passing times, m represents the total order of the resonant frequency, P i represents the acceleration power spectrum density value corresponding to the i-th order resonance frequency, f i represents the i-th order resonant frequency value, Q i represents the transmission rate obtained by the i-th order resonant frequency, Ω i represents the i-th order natural circular frequency.

5. The method for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment according to claim 3, characterized in that: The relationship between the elastic strain range and the fatigue cycle number is expressed as: Δε iσ represents the elastic strain range of random vibration excitation in the iσ interval, σ u represents the tensile strength of the component to be predicted, E represents the elastic modulus, N iσ represents the number of fatigue cycles of random vibration excitation in the iσ interval, and σ is the variance of the normal distribution of random vibration excitation.

6. The method for calculating the environmental coefficient of electronic components in a preset temperature and vibration environment according to claim 3, characterized in that: The formula for random vibration calculation is expressed as: Among them, D V represents the random vibration damage, represents the number of positive zero passes, N 1σ 、N 2σ and N 3σ It corresponds to the number of fatigue cycles of random vibration excitation in the intervals of 1σ, 2σ and 3σ, and σ is the variance of the normal distribution of random vibration excitation.

7. The method for calculating the environmental coefficient of electronic components in a preset temperature and vibration environment according to claim 1, characterized in that: The temperature cycle damage and the random vibration damage are superimposed, and the total life of the component to be predicted is calculated according to the result of the damage superposition and Miner's law, including: According to a preset weighting ratio, the temperature cycle damage and the random vibration damage are summed to obtain the total damage of the component to be predicted; The total life of the component to be predicted is obtained by taking the inverse of the total damage.

8. The method for calculating the environmental coefficient of electronic components in a preset temperature and vibration environment according to claim 1, characterized in that: Based on the total life and the electronic equipment reliability prediction handbook, the influence of the packaging factor in the failure rate is removed to obtain the environmental coefficient of the component to be predicted under the preset temperature cycle conditions, including: Calculating the failure rate λ of the component to be predicted based on the total life and a first preset formula; By using the electronic equipment reliability prediction manual, the packaging complexity failure rate C3 of the component to be predicted is obtained by looking up the table; The environmental coefficient is obtained by using a second preset formula, the failure rate λ and the packaging complexity failure rate C3; Wherein, the first preset formula is expressed as: N represents the total life span; The second preset formula is expressed as: C3 represents the packaging complexity failure rate, π E represents the environmental factor.

9. A device for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment, characterized in that: The device for calculating the environmental coefficient of electronic components under a preset temperature and vibration environment comprises: a model building unit, a temperature simulation unit, a vibration simulation unit and a calculation unit; The model building unit is used to: build a finite element model according to the structural parameters of the components to be predicted; The temperature simulation unit is used to: perform temperature cycle simulation on the finite element model, and calculate temperature cycle damage according to the result of the temperature cycle simulation and Miner's law; The vibration simulation unit is used to: perform random vibration simulation on the finite element model using a preset temperature cycle condition as a prestress, and calculate random vibration damage according to the result of the random vibration simulation and Miner's law; The calculation unit is used to: perform damage superposition on the temperature cycle damage and the random vibration damage, and calculate the total life of the component to be predicted according to the damage superposition result and Miner's law; The calculation unit is also used to obtain the environmental coefficient of the component to be predicted under preset temperature cycle conditions based on the total life and the electronic equipment reliability prediction manual.

10. An environmental coefficient calculation device for electronic components in a preset temperature and vibration environment, characterized in that: include: A processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor. When the environmental coefficient calculation device is running, the processor communicates with the storage medium via the bus, and the processor executes the machine-readable instructions to perform the steps of the environmental coefficient calculation method as described in any one of claims 1 to 8.

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