CN106709175A - Method for obtaining material mechanical property parameters of printed circuit board - Google Patents
Method for obtaining material mechanical property parameters of printed circuit board Download PDFInfo
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- CN106709175A CN106709175A CN201611163597.7A CN201611163597A CN106709175A CN 106709175 A CN106709175 A CN 106709175A CN 201611163597 A CN201611163597 A CN 201611163597A CN 106709175 A CN106709175 A CN 106709175A
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/30—Circuit design
- G06F30/39—Circuit design at the physical level
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/17—Mechanical parametric or variational design
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/23—Design optimisation, verification or simulation using finite element methods [FEM] or finite difference methods [FDM]
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- Pure & Applied Mathematics (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
- Tests Of Electronic Circuits (AREA)
Abstract
The invention discloses a method for obtaining material mechanical properties of a printed circuit board, and belongs to the technical field of finite element mode analysis and testing. Conventional circuit board material property assignment of the printed circuit board subjected to finite element strength analysis depends on experience, and that accurate assignment ensures accuracy of finite element modeling becomes a problem. The method comprises the steps of firstly establishing an LMS mode analysis test system, performing setting of hardware, software and an excitation system, and performing testing by adopting a hammering method to obtain a resonant frequency and a vibration mode of the printed circuit board in a free state; building a printed circuit board finite element model by utilizing finite element analysis software Hypermesh, and promoting the resonant frequency and the vibration mode, in the free state, obtained by finite element mode analysis to be close to those obtained in the mode analysis test system by adjusting material mechanical property parameters of the printed circuit board based on experience values; and determining that the material mechanical property parameters of the printed circuit board set in the Hypermesh are accurate under the condition that the vibration modes of all orders are consistent and a resonant frequency error is within 5%.
Description
Technical field
The invention belongs to finite element modal analysis and technical field of measurement and test, it is related to a kind of acquisition printed circuit board circuit material
The method of mechanics parameters.
Background technology
The random vibration that air environment can be caused during takeoff and landing, airflight by many factors is carried
The influence of lotus, shock loading, acceleration load etc..Realize that equipment uses each of function by what printed circuit board and component were constituted
Module is the important component of air environment, and can its Structural Dynamics performance direct relation equipment electric signal effective
Transmission, and then affect the reliability of air environment.Therefore, finite Element Intensity Analysis are carried out to equipment and investigates each module print
Circuit board vibration characteristics processed is particularly important.And the characteristic of material mechanics parameter such as printed circuit board density, elastic model, Poisson's ratio
Whether setting correctly directly affects precision of analysis.And its mechanical characteristic is because of the difference of manufacturer, manufacturing process etc.
And it is different, lead to not accurately be obtained by the conventional method such as table look-up the characteristic of material mechanics parameter of printed circuit board；At present, exist
When carrying out finite Element Intensity Analysis, printed circuit board plate material characteristic assignment is all that by virtue of experience, precise value ensures finite element
The accuracy of modeling is into a problem.
The content of the invention
Join it is an object of the invention to provide a kind of accurate air environment printed circuit board characteristic of material mechanics that obtains
Several methods is inaccurate to solve assignment during air environment finite Element Intensity Analysis, it is impossible to ensure asking for modeling accuracy
Topic.
Principle of the invention is：LMS model analysis test systems are built first, carry out hardware, software and excitation system
Set, using hammering method, test obtains the intrinsic frequency and the vibration shape under air environment printed circuit board free state.It is sharp again
Air environment printed circuit board FEM model is set up with finite element analysis software Hypermesh, on the basis of empirical value
On promote finite element modal analysis by adjusting the characteristic of material mechanics parameter such as printed circuit board density, elastic model, Poisson's ratio
Intrinsic frequency and the vibration shape that intrinsic frequency under the free state for obtaining is obtained close to it with the vibration shape in model analysis test system.
Each rank formation is consistent and intrinsic frequency error within 5% i.e. it is believed that the printing electricity set in Hypermesh in the case of this
The parameters such as road plate elastic model, Poisson's ratio are accurate.It can be the finite Element Intensity Analysis mould set up under accurate working condition
Type provides foundation, so as to ensure the validity of the whole machine Finite element analysis results of air environment.
The technical scheme is that：
A kind of method for obtaining printed circuit board material mechanics parameters, it is characterised in that：Comprise the following steps：
Step 1：LMS model analysis test systems are built, mould measurement point is arranged, the mould of tested printed circuit board is set up
State test model；
Step 2：The parameter setting of excitation system is carried out in LMS mould measurement softwares, test obtains tested printing electricity
Intrinsic frequency and the vibration shape under the plate free state of road；
Step 3：The FEM model of printed circuit board is set up using finite element analysis software；
Step 4：Printed circuit board density, elastic modelling quantity, Poisson's ratio in adjustment FEM model, make finite element modal analysis
The intrinsic frequency that at least preceding 3 rank intrinsic frequency and printed circuit board under the free state for obtaining are obtained in model analysis test system
Rate error is not more than 5%, and the vibration shape is consistent；
Step 5：Adjustment result according to step 4, determines printed circuit board density, elastic modelling quantity, Poisson's ratio.
Further preferred scheme, a kind of method for obtaining printed circuit board material mechanics parameters, its feature
It is：In the LMS model analyses test system, tested printed circuit board is placed on spring rope, with free state；
If being done in the selection of tested printed circuit board, wherein 1 point used as excitation point, remaining point is as measuring point and sets acceleration sensing
Device；Firmly hammer taps excitation point when tested, and the acceleration transducer and measuring point acceleration transducer on power hammer will can be tested
Signal passes LMS mould measurement data collecting instruments back；Coordinate information according to measuring point and excitation point in LMS DAS is built
The mould measurement model of vertical tested printed circuit board.
Further preferred scheme, a kind of method for obtaining printed circuit board material mechanics parameters, its feature
It is：In step 2, excitation point is repeatedly tapped using hammering method, LMS mould measurements software is adopted by mould measurement data collecting instrument
Collection signal data, obtains the intrinsic frequency and formation under printed circuit board free state.
Further preferred scheme, a kind of method for obtaining printed circuit board material mechanics parameters, its feature
It is：In step 3, the FEM model of printed circuit board is set up using finite element analysis software, printed circuit board is improved quality
Electronic component more than 5g is reduced to quality point, and according to electronic component in practice and the connection status pair of printed circuit board
Quality point carries out contact setting with printed circuit board regional area surface grids.
Further preferred scheme, a kind of method for obtaining printed circuit board material mechanics parameters, its feature
It is：In step 4, the corresponding printed circuit board density of FEM model, elastic modelling quantity, the empirical value of Poisson's ratio are density
1.85e-9t/mm3, elastic modulus E is 2.2e4MPa, Poisson's ratio 0.28.
Beneficial effect
The method is also carried out while printed circuit board material mechanics parameters are obtained to its finite element analysis model
Correction, is set in it when can be deformation, the equivalent stress under finite element analysis software whole air environment working condition
The printed circuit board parameter in portion provides foundation, it is ensured that the accuracy of analysis.
Additional aspect of the invention and advantage will be set forth in part in the description, and will partly become from the following description
Obtain substantially, or recognized by practice of the invention.
Brief description of the drawings
Of the invention above-mentioned and/or additional aspect and advantage will become from description of the accompanying drawings below to embodiment is combined
Substantially and be readily appreciated that, wherein：
The printed circuit board LMS model analysis test system pictorial diagrams that Fig. 1 builds
The rank Free Modal formation of Fig. 2 printed circuit boards mould measurement 1, wherein lines 1 are the mould measurement node point set up
Analysis model, lines 2 are mould measurement formation, and 1 rank Free Modal frequency is 74Hz.
The rank Free Modal formation of Fig. 3 printed circuit boards mould measurement 2,2 rank Free Modal frequencies are 87Hz.
The rank Free Modal formation of Fig. 4 printed circuit boards mould measurement 3,3 rank Free Modal frequencies are 172.5Hz.
The rank Free Modal formation of Fig. 5 printed circuit board finite element software Hypermesh model analyses 1,1 rank Free Modal is frequently
Rate is 77.7Hz.
The rank Free Modal formation of Fig. 6 printed circuit board finite element software Hypermesh model analyses 2,2 rank Free Modals are frequently
Rate is 89Hz.
The rank Free Modal formation of Fig. 7 printed circuit board finite element software Hypermesh model analyses 3,3 rank Free Modals are frequently
Rate is 167.7Hz.
Specific embodiment
Embodiments of the invention are described below in detail, the embodiment is exemplary, it is intended to for explaining the present invention, and
It is not considered as limiting the invention.
Join it is an object of the invention to provide a kind of accurate air environment printed circuit board characteristic of material mechanics that obtains
Several methods is inaccurate to solve assignment during air environment finite Element Intensity Analysis, it is impossible to ensure asking for modeling accuracy
Topic.
LMS model analysis test systems are built first, carry out the setting of hardware, software and excitation system, using hammering method,
Test obtains the intrinsic frequency and the vibration shape under air environment printed circuit board free state.Recycle finite element analysis software
Hypermesh sets up air environment printed circuit board FEM model, by adjusting printing electricity on the basis of empirical value
The characteristic of material mechanics parameters such as road plate density, elastic model, Poisson's ratio promote under the free state that finite element modal analysis are obtained
Intrinsic frequency and the vibration shape intrinsic frequency and the vibration shape that are obtained in model analysis test system close to it.Each rank formation it is consistent and
Intrinsic frequency error is within 5% i.e. it is believed that the printed circuit board elastic model, the Poisson that are set in Hypermesh in the case of this
Than etc. parameter be accurate.Foundation can be provided for the finite Element Intensity Analysis model set up under accurate working condition, so as to protect
Demonstrate,prove the validity of the whole machine Finite element analysis results of air environment.
Specifically include following steps：
Step 1：LMS model analysis test systems are built, mould measurement point is arranged, mould measurement model is set up.
LMS model analysis test systems are built as shown in Figure 1.Tested printed circuit board is placed on the spring rope of softness
On be at free state.Size, LMS mould measurement data collecting instrument port numbers according to printed circuit board is in tested print
Reasonable Arrangement mould measurement points and position on circuit board processed.Printed circuit board belongs to thin plate class zero in finite element analysis
Part, can be reduced to a face in finite element analysis model and mould measurement model, and its actual size is long × a width of 207mm ×
156mm, 12 are uniformly chosen according to tested printed circuit board size and its component distribution situation above on a printed circuit board
It is individual, wherein 1 point is set to excitation point, hammer of being exerted oneself in test taps the point, and remaining 11 point adds as measuring point is default
Velocity sensor, the acceleration transducer that acceleration transducer and 11 measuring points on power hammer go out can pass test signal back LMS
Mould measurement data collecting instrument.Coordinate information according to measuring point and excitation point in LMS DAS sets up printed circuit
The mould measurement model of plate, the lines 1 seen in accompanying drawing 2.
Step 2：The parameter setting of excitation system is carried out in LMS mould measurement softwares, test obtains printed circuit board certainly
By intrinsic frequency and the vibration shape under state.
Especially to consider that 11 measuring points and power hammer beating point are passed during excitation system parameter setting in LMS mould measurement softwares
The setting in sensor direction, printed circuit board point tow sides, if 11 measuring point sensor methods are not to complete with power hammer beating point normal direction
It is complete consistent, could dictate that printed circuit board one side normal direction for just, another side normal direction is negative.
Hammering method repeatedly taps excitation point, and LMS mould measurements software can gather signal by mould measurement data collecting instrument
Data, and automatic decision multi-group data correlation and validity.Processed by software data, can obtain printed circuit board freedom
Intrinsic frequency and formation under state, present invention citing only provide before its Modal testing and analysis 3 rank Free Modal formations and intrinsic
Frequency, is shown in accompanying drawing 2- Fig. 4.
Step 3：The FEM model of printed circuit board is set up using finite element analysis software Hypermesh.
The finite element analysis model of printed circuit board is set up using finite element analysis software Hypermesh, is improved quality
Electronic component more than 5g is reduced to multiple quality point RBE3, and according to being fixedly connected situation with printed circuit board in practice
Quality point and printed circuit board regional area surface grids are carried out into contact setting.
Step 4：The characteristic of material mechanics parameters such as adjustment printed circuit board density, elastic modelling quantity, Poisson's ratio promote finite element
The intrinsic frequency of at least preceding 3 rank and its intrinsic frequency obtained in model analysis test system under the free state that model analysis is obtained
Rate error is not more than 5%, and the vibration shape is consistent.
In empirical value printed circuit board density 1.85e-9t/mm3, elastic modelling quantity is 2.2e4MPa, the base of Poisson's ratio 0.28
Mechanics parameters are adjusted on plinth, the formation obtained until finite element software Hypermesh model analyses is consistent, intrinsic frequency becomes
In close.Preferable analysis result is repeatedly obtained after adjustment, present invention citing only provides 3 rank Free Modals before its finite element analysis
Formation and intrinsic frequency its formation are shown in Fig. 5-Fig. 7.
Step 5：Further comparative analysis, determines the mechanics of materials such as printed circuit board current densities, elastic modelling quantity, Poisson's ratio
Characterisitic parameter.
Finite element analysis model analysis is obtained with LMS mould measurement system testings Its comparative analysis the results are shown in Table 1.Preceding 3 rank is intrinsic
Relative difference on frequency is 5% to the maximum, meets expected precision 5% and requires, you can thinks finite element software model analysis in the case of this
The printed circuit board mechanics parameters of middle setting are accurate, printed circuit board density 2e-9t/mm3, elastic modulus E is
1.95e4MPa, Poisson's ratio 0.28.
Finite element modal analysis result and Modal testing and analysis result pair after the adjustment printed circuit board mechanics parameters of table 1
Than.
Although embodiments of the invention have been shown and described above, it is to be understood that above-described embodiment is example
Property, it is impossible to limitation of the present invention is interpreted as, one of ordinary skill in the art is not departing from principle of the invention and objective
In the case of above-described embodiment can be changed within the scope of the invention, change, replace and modification.
Claims (5)
1. it is a kind of obtain printed circuit board material mechanics parameters method, it is characterised in that：Comprise the following steps：
Step 1：LMS model analysis test systems are built, mould measurement point is arranged, the mode for setting up tested printed circuit board is surveyed
Die trial type；
Step 2：The parameter setting of excitation system is carried out in LMS mould measurement softwares, test obtains tested printed circuit board
Intrinsic frequency and the vibration shape under free state；
Step 3：The FEM model of printed circuit board is set up using finite element analysis software；
Step 4：Printed circuit board density, elastic modelling quantity, Poisson's ratio in adjustment FEM model, obtain finite element modal analysis
Free state under at least preceding 3 rank intrinsic frequency and the intrinsic frequency that obtains in model analysis test system of printed circuit board miss
Difference is not more than 5%, and the vibration shape is consistent；
Step 5：Adjustment result according to step 4, determines printed circuit board density, elastic modelling quantity, Poisson's ratio.
2. according to claim 1 it is a kind of obtain printed circuit board material mechanics parameters method, it is characterised in that：Institute
State in LMS model analysis test systems, tested printed circuit board is placed on spring rope, with free state；Tested
If examination printed circuit board selection is done, wherein 1 point used as excitation point, remaining point is as measuring point and sets acceleration transducer；When
Exert oneself to hammer into shape during test and tap excitation point, the acceleration transducer and measuring point acceleration transducer on power hammer can pass test signal
Return LMS mould measurement data collecting instruments；Coordinate information according to measuring point and excitation point in LMS DAS sets up tested
Try the mould measurement model of printed circuit board.
3. according to claim 1 it is a kind of obtain printed circuit board material mechanics parameters method, it is characterised in that：Step
In rapid 2, excitation point is repeatedly tapped using hammering method, LMS mould measurements software gathers signal by mould measurement data collecting instrument
Data, obtain the intrinsic frequency and formation under printed circuit board free state.
4. according to claim 1 it is a kind of obtain printed circuit board material mechanics parameters method, it is characterised in that：Step
In rapid 3, the FEM model of printed circuit board is set up using finite element analysis software, printed circuit board is improved quality more than 5g's
Electronic component is reduced to quality point, and according to the connection status of electronic component in practice and printed circuit board to quality point with
Printed circuit board regional area surface grids carry out contact setting.
5. according to claim 1 it is a kind of obtain printed circuit board material mechanics parameters method, it is characterised in that：Step
In rapid 4, the corresponding printed circuit board density of FEM model, elastic modelling quantity, the empirical value of Poisson's ratio are density 1.85e-9t/
mm3, elastic modulus E is 2.2e4MPa, Poisson's ratio 0.28.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611163597.7A CN106709175A (en) | 2016-12-16 | 2016-12-16 | Method for obtaining material mechanical property parameters of printed circuit board |
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| CN201611163597.7A CN106709175A (en) | 2016-12-16 | 2016-12-16 | Method for obtaining material mechanical property parameters of printed circuit board |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110705149A (en) * | 2019-09-20 | 2020-01-17 | 博格华纳汽车零部件（武汉）有限公司 | Motor stator mode calculation method |
| CN110866346A (en) * | 2019-11-21 | 2020-03-06 | 国网陕西省电力公司电力科学研究院 | Method and system for acquiring inherent vibration characteristics of dry-type air-core reactor |
| CN112859592A (en) * | 2020-12-29 | 2021-05-28 | 中国航空工业集团公司西安飞机设计研究所 | Method for controlling structural modal frequency of turboprop aircraft |
| CN113962180A (en) * | 2021-12-16 | 2022-01-21 | 中大检测(湖南)股份有限公司 | Optimization method for analyzing position of acceleration sensor on PCB based on FEA |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110705149A (en) * | 2019-09-20 | 2020-01-17 | 博格华纳汽车零部件（武汉）有限公司 | Motor stator mode calculation method |
| CN110705149B (en) * | 2019-09-20 | 2023-03-14 | 博格华纳汽车零部件（武汉）有限公司 | Motor stator mode calculation method |
| CN110866346A (en) * | 2019-11-21 | 2020-03-06 | 国网陕西省电力公司电力科学研究院 | Method and system for acquiring inherent vibration characteristics of dry-type air-core reactor |
| CN110866346B (en) * | 2019-11-21 | 2023-02-07 | 国网陕西省电力公司电力科学研究院 | Method and system for acquiring inherent vibration characteristics of dry-type air-core reactor |
| CN112859592A (en) * | 2020-12-29 | 2021-05-28 | 中国航空工业集团公司西安飞机设计研究所 | Method for controlling structural modal frequency of turboprop aircraft |
| CN113962180A (en) * | 2021-12-16 | 2022-01-21 | 中大检测(湖南)股份有限公司 | Optimization method for analyzing position of acceleration sensor on PCB based on FEA |
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Application publication date: 20170524 |