CN108709937A - A kind of test device and test method of strain measurement-cantilever beam free damping coefficient - Google Patents
A kind of test device and test method of strain measurement-cantilever beam free damping coefficient Download PDFInfo
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- CN108709937A CN108709937A CN201810778320.8A CN201810778320A CN108709937A CN 108709937 A CN108709937 A CN 108709937A CN 201810778320 A CN201810778320 A CN 201810778320A CN 108709937 A CN108709937 A CN 108709937A
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- cantilever beam
- strain
- foil gauge
- damping coefficient
- test device
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- 238000012360 testing method Methods 0.000 title claims abstract description 41
- 238000013016 damping Methods 0.000 title claims abstract description 22
- 238000010998 test method Methods 0.000 title claims abstract description 9
- 239000011888 foil Substances 0.000 claims abstract description 30
- 239000000463 material Substances 0.000 claims abstract description 11
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 claims abstract description 8
- 238000005259 measurement Methods 0.000 claims description 8
- 230000000694 effects Effects 0.000 claims description 4
- 238000012956 testing procedure Methods 0.000 claims description 3
- 239000000725 suspension Substances 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims 1
- 238000000034 method Methods 0.000 abstract description 5
- 238000001514 detection method Methods 0.000 abstract description 3
- 238000002474 experimental method Methods 0.000 abstract description 3
- 230000007547 defect Effects 0.000 abstract 1
- 230000001419 dependent effect Effects 0.000 abstract 1
- 230000001133 acceleration Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 238000012790 confirmation Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
- G01N29/11—Analysing solids by measuring attenuation of acoustic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/16—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring the deformation in a solid, e.g. by resistance strain gauge
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
- G01N29/045—Analysing solids by imparting shocks to the workpiece and detecting the vibrations or the acoustic waves caused by the shocks
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/01—Indexing codes associated with the measuring variable
- G01N2291/015—Attenuation, scattering
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/023—Solids
- G01N2291/0234—Metals, e.g. steel
Abstract
A kind of test device and test method of strain measurement-cantilever beam free damping coefficient, belong to material property detection technique field.The present invention solves existing experiment process complexity, the excessively high defect of experimentation cost.Technical essential：Cantilever beam one end is fixed in the fixed seat of pedestal；Foil gauge attaches on a cantilever beam；The vertical portion of fixture is established by rotating assembly and bottom plate and is connected；Fin neck bolt is fixed on the horizontal part of fixture, and fin neck bolt is located at right over the free end of cantilever beam；Strain testing instrument input terminal connects foil gauge by conducting wire, and output end connects computer.Change the size of cantilever beam free end exciting force by adjusting the elongation of fin neck bolt, periodically, dependent variable is definite value to bolt elongate amount one at Computer display foil gauge；Fixture, cantilever beam vibration are quickly removed to the right；Foil gauge signal is acquired by strain testing instrument, strain-time graph is obtained in computer；Calculate the attenuation coefficient of cantilever beam.The present invention is used for cantilever material performance detection.
Description
Technical field
The present invention relates to a kind of test devices and test method of cantilever beam attenuation coefficient, and in particular to a kind of strain survey
The test device and test method of amount-cantilever beam free damping coefficient, belong to material property detection technique field.
Background technology
Metal has under one-way circulation stress or alternative cycle stress, irreversibly to absorb energy without broken
Bad ability, this ability are obtained indirectly by attenuation curve.Conventional methods are changed over time by vibration acceleration
As a result it obtains attenuation curve, and often needs the exciting device of complex and expensive.
Invention content
The brief overview about the present invention is given below, in order to provide about the basic of certain aspects of the invention
Understand.It should be appreciated that this general introduction is not the exhaustive general introduction about the present invention.It is not intended to determine the pass of the present invention
Key or pith, nor is it intended to limit the scope of the present invention.Its purpose only provides certain concepts in simplified form,
In this, as the preamble in greater detail discussed later.
In consideration of it, the present invention changes over time result to obtain to solve existing research technique by vibration acceleration
Attenuation curve, testing equipment exciting device is complicated and expensive in the process, causes experiment process complicated, and experimentation cost is excessively high to be lacked
It falls into, and then devises a kind of test device and test method of easy strain measurement-cantilever beam free damping coefficient.
The scheme one that the present invention is taken：A kind of test device of strain measurement-cantilever beam free damping coefficient, including base
Seat, cantilever beam, foil gauge, conducting wire, fin neck bolt, fixture, rotating assembly, strain testing instrument, computer；The pedestal includes bottom
Plate and the fixed seat being vertically mounted on bottom plate；Described cantilever beam one end is fixed in fixed seat, other end suspension；The strain
Piece attaches on a cantilever beam；The fixture includes vertically disposed vertical part and the horizontal part, and vertical portion passes through rotating assembly and bottom
Plate establishes connection；The fin neck bolt is fixed on the horizontal part of fixture, and fin neck bolt is located at right over the free end of cantilever beam；
The strain testing instrument input terminal connects foil gauge by conducting wire, and output end connects computer.
Further：The cantilever beam is the beam of uniform strength, ensures that the strain of any position on surface is also equal.
Further：The foil gauge is unidirectional foil gauge.
Further：The strain gauge adhesion direction is along cantilever beam length direction.
Further：The strain gauge adhesion position is to ensure that different materials are outstanding at 1/3 length of cantilever beam fixing end
Foil gauge is located at same position when arm beam is tested.
Further：The fin neck bolt is connected through a screw thread mode and is fixed on fixture, in bolt length allowable range
It is interior, it can arbitrarily the adjusting bolt amount of feeding, i.e. exciting force size can freely adjust.
Further：The rotating assembly includes shaft seat and pivot pin, and shaft seat is mounted on bottom plate, and pivot pin will be for that will block
The vertical portion bottom end of tool is established with shaft seat and is connected.
Further：The strain testing instrument is PCD-300A strain testing instrument, which strains for common universality
Instrument.
Scheme two：A kind of test method of strain measurement-cantilever beam free damping coefficient, is described in support scheme one
What a kind of test device of strain measurement-cantilever beam free damping coefficient was realized, specific testing procedure is：
First, change the size of cantilever beam free end exciting force by adjusting the elongation of fin neck bolt；Fin neck bolt
The timing of elongation one, the strain magnitude of cantilever beam at Computer display foil gauge；
Secondly, fixture is quickly removed outward, cantilever beam vibrates under exciting force effect；
Then, the signal of foil gauge is acquired by strain testing instrument, computer obtains strain-time graph；
Finally, by strain-time changing curve along cantilever beam direction, reflect the Vibration Condition of cantilever beam indirectly, from
It vibrates starting point and chooses 7 complete wave crests, cantilever beam attenuation coefficient is calculated using attenuation coefficient formula, to according to material in-fighting
Value Q-1Judgement material anti-vibration property completes test.
The attenuation coefficient formula is：η=An/An+1；
Wherein --- η is attenuation coefficient；
——An、An+1For two amplitudes of arbitrary neighborhood；
Logarithmic decrement coefficient formula is：δ=㏑ (An/An+1)；
Wherein --- δ logarithmic decrement coefficients；
Material Internal friction Q-1=1/2 π (1-e-2δ)；
Wherein --- Q material in-fighting.
The effect that is reached of the present invention is：
The present invention devises a kind of fixture applying fixed exciting force, and cantilever beam vibration is made under certain exciting force,
Pass through the time-domain curve strained when vibration and calculates attenuation coefficient.Since a kind of simple fixture is utilized as excitation apparatus, protect
Initial strain amount is consistent during confirmation is tested, and experiment process is simple, and experimentation cost is low.
Description of the drawings
Fig. 1 is a kind of structural schematic diagram of the test device of strain measurement-cantilever beam free damping coefficient of the present invention；
In figure：
1, pedestal；2, cantilever beam；3, foil gauge；4, conducting wire；5, fin neck bolt；6, fixture；7, rotating assembly；8, strain is surveyed
Try instrument；9, computer.
Specific implementation mode
For clarity and conciseness, all features of actual implementation mode are not described in the description.However, should
Understand, much decisions specific to embodiment must be made during developing any this practical embodiments, so as to reality
The objectives of existing developer, for example, meet restrictive condition those of related to system and business, and these restrictive conditions
It may be changed with the difference of embodiment.In addition, it will also be appreciated that although development is likely to be very multiple
It is miscellaneous and time-consuming, but for the those skilled in the art for having benefited from the disclosure of invention, this development is only example
Capable task.
Herein, it is also necessary to which explanation is a bit, in order to avoid having obscured the present invention because of unnecessary details, in application text
It illustrate only the apparatus structure closely related with scheme according to the present invention and/or processing step in part, and be omitted and this
The little other details of inventive relationship.
Embodiment：Referring to Fig. 1, a kind of test device of strain measurement-cantilever beam free damping coefficient of present embodiment,
Including pedestal 1, cantilever beam 2, foil gauge 3, conducting wire 4, fin neck bolt 5, fixture 6, rotating assembly 7, strain testing instrument 8, computer
9；The pedestal 1 includes bottom plate and the fixed seat being vertically mounted on bottom plate；2 one end of the cantilever beam is fixed in fixed seat,
The other end suspends；The foil gauge 3 attaches on the cantilever beam 2；The fixture 6 includes vertically disposed vertical part and the horizontal part,
Vertical portion is established by rotating assembly 7 and bottom plate and is connected；The fin neck bolt 5 is fixed on the horizontal part of fixture 6, and fin neck bolt
5 are located at right over the free end of cantilever beam 2；8 input terminal of strain testing instrument connects foil gauge 3 by conducting wire 4, and output end connects
Connect computer 9.
More specifically：The cantilever beam 2 is the beam of uniform strength.
More specifically：The foil gauge 3 is unidirectional foil gauge.
More specifically：It is along cantilever beam length direction that the foil gauge 3, which pastes direction,.
More specifically：3 paste position of the foil gauge is at 2 fixing end of cantilever beam, 1/3 length.
More specifically：The mode that the fin neck bolt 5 is connected through a screw thread is fixed on fixture 6.
More specifically：The rotating assembly 7 includes shaft seat and pivot pin, and shaft seat is mounted on bottom plate, and pivot pin is used for
The vertical portion bottom end of fixture 6 and shaft seat are established and connected.
More specifically：The strain testing instrument 8 is PCD-300A strain testing instrument.
A kind of test method of strain measurement of present embodiment-cantilever beam free damping coefficient is that support is described
What a kind of test device of strain measurement-cantilever beam free damping coefficient was realized, specific testing procedure is：
First, change the size of 2 free end exciting force of cantilever beam by adjusting the elongation of fin neck bolt 5；Tip spiral shell
One timing of elongation of bolt 5, computer 9 show the strain magnitude of cantilever beam at foil gauge 3；
Secondly, fixture 6 is quickly removed outward, cantilever beam 2 vibrates under exciting force effect；
Then, the signal of foil gauge 3 is acquired by strain testing instrument 8, computer 9 obtains strain-time graph；
Finally, by strain-time changing curve along cantilever beam direction, reflect the Vibration Condition of cantilever beam indirectly, from
It vibrates starting point and chooses 7 complete wave crests, cantilever beam attenuation coefficient is calculated using attenuation coefficient formula, to judgement material weakening
Performance completes test.
The present embodiment passes through the time-domain curve strained when vibration and calculates attenuation coefficient, while a kind of simple fixture is utilized
As excitation apparatus, ensure that initial strain amount is consistent in experimentation.
Although disclosed embodiment is as above, its content is only to facilitate understand the technical side of the present invention
Case and the embodiment used, are not intended to limit the present invention.Any those skilled in the art to which this invention pertains, not
Under the premise of being detached from disclosed core technology scheme, any modification and change can be made in form and details in implementation
Change, but protection domain defined by the present invention, the range that the appended claims that must still be subject to limits.
Claims (9)
1. a kind of test device of strain measurement-cantilever beam free damping coefficient, it is characterised in that：Including pedestal (1), cantilever beam
(2), foil gauge (3), conducting wire (4), fin neck bolt (5), fixture (6), rotating assembly (7), strain testing instrument (8), computer
(9)；The pedestal (1) includes bottom plate and the fixed seat that is vertically mounted on bottom plate；Fixation is fixed in described cantilever beam (2) one end
On seat, other end suspension；The foil gauge (3) is attached on cantilever beam (2)；The fixture (6) includes vertically disposed vertical
Portion and horizontal part, vertical portion are established by rotating assembly 7 and bottom plate and are connected；The fin neck bolt (5) is fixed on the water of fixture (6)
Flat portion, and fin neck bolt (5) is located at right over the free end of cantilever beam (2)；Strain testing instrument (8) input terminal passes through conducting wire
(4) connection foil gauge (3), output end connect computer (9).
2. a kind of test device of strain measurement according to claim 1-cantilever beam free damping coefficient, feature exist
In：The cantilever beam (2) is the beam of uniform strength.
3. a kind of test device of strain measurement according to claim 2-cantilever beam free damping coefficient, feature exist
In：The foil gauge (3) is unidirectional foil gauge.
4. a kind of test device of strain measurement according to claim 3-cantilever beam free damping coefficient, feature exist
In：It is along cantilever beam length direction that the foil gauge (3), which pastes direction,.
5. a kind of test device of strain measurement according to claim 4-cantilever beam free damping coefficient, feature exist
In：Foil gauge (3) paste position is at 1/3 length of cantilever beam (2) fixing end.
6. a kind of test device of strain measurement according to claim 5-cantilever beam free damping coefficient, feature exist
In：Fin neck bolt (5) mode of being connected through a screw thread is fixed on fixture (6).
7. a kind of test device of strain measurement according to claim 1-cantilever beam free damping coefficient, feature exist
In：The rotating assembly (7) includes shaft seat and pivot pin, and shaft seat is mounted on bottom plate, and pivot pin is used for the vertical of fixture (6)
Portion bottom end is established with shaft seat and is connected.
8. a kind of test device of strain measurement according to claim 1-cantilever beam free damping coefficient, feature exist
In：The strain testing instrument (8) is PCD-300A strain testing instrument.
9. a kind of test method of strain measurement-cantilever beam free damping coefficient is to rely on claim 1-8 any described
What a kind of test device of strain measurement-cantilever beam free damping coefficient was realized, which is characterized in that specific testing procedure is：
First, change the size of cantilever beam (2) free end exciting force by adjusting the elongation of fin neck bolt (5)；Tip spiral shell
One timing of elongation of bolt (5), computer (9) show the strain magnitude of cantilever beam at foil gauge (3)；
Secondly, fixture (6) is quickly removed outward, cantilever beam (2) vibrates under exciting force effect；
Then, the signal of foil gauge (3) is acquired by strain testing instrument (8), computer (9) obtains strain-time graph；
Finally, by strain-time changing curve along cantilever beam direction, reflect the Vibration Condition of cantilever beam indirectly, from vibration
Starting point chooses 7 complete wave crests, cantilever beam attenuation coefficient is calculated using attenuation coefficient formula, to big according to material Internal friction
Small judgement material anti-vibration property completes test.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810778320.8A CN108709937A (en) | 2018-07-16 | 2018-07-16 | A kind of test device and test method of strain measurement-cantilever beam free damping coefficient |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810778320.8A CN108709937A (en) | 2018-07-16 | 2018-07-16 | A kind of test device and test method of strain measurement-cantilever beam free damping coefficient |
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| Publication Number | Publication Date |
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| CN108709937A true CN108709937A (en) | 2018-10-26 |
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| CN201810778320.8A Pending CN108709937A (en) | 2018-07-16 | 2018-07-16 | A kind of test device and test method of strain measurement-cantilever beam free damping coefficient |
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|---|---|---|---|---|
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-
2018
- 2018-07-16 CN CN201810778320.8A patent/CN108709937A/en active Pending
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|---|---|---|---|---|
| CN101327849A (en) * | 2008-06-18 | 2008-12-24 | 华南理工大学 | Jet type driver-based apparatus and method for inhibiting flexibility structural vibration |
| CN101656176A (en) * | 2009-08-14 | 2010-02-24 | 清华大学 | Bistable state nano cantilever switch using floating gate electrode |
| CN201803792U (en) * | 2009-12-17 | 2011-04-20 | 天津工业大学 | Device for vibration test of light-weight fiber reinforced composite cantilever plate |
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Application publication date: 20181026 |