CN101832970B - Device and method for reckoning fatigue crack propagation rate of flat alloy by AC potentiometry - Google Patents
Device and method for reckoning fatigue crack propagation rate of flat alloy by AC potentiometry Download PDFInfo
- Publication number
- CN101832970B CN101832970B CN2010101661431A CN201010166143A CN101832970B CN 101832970 B CN101832970 B CN 101832970B CN 2010101661431 A CN2010101661431 A CN 2010101661431A CN 201010166143 A CN201010166143 A CN 201010166143A CN 101832970 B CN101832970 B CN 101832970B
- Authority
- CN
- China
- Prior art keywords
- potential
- crack propagation
- flat
- fatigue
- lead
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
The invention provides a device and a method for reckoning the fatigue crack propagation rate of a flat alloy by AC potentiometry, relating to the field of detecting material fatigue performance. The method comprises the following steps: in the process of a tension-tension fatigue test, two pairs of probes are arranged on the surface of a flat alloy sample, and the sample monitors electric potential change at the two sides of a crack in real time by an AC potentiometry sensor thereon when the fatigue crack propagates; the electric potential change is transmitted to a dual-trace oscilloscope by an amplifier; the dual-trace oscilloscope displays the electric potential oscillogram of the propagation of the two ends of the crack; and the electric potential oscillogram is input to a computer by an A/D converter, and is analyzed by a bundled software to obtain fatigue propagation rate such as the fatigue crack propagation rate and the like. The device of the invention mainly comprises a fatigue-testing machine, sample fixtures, the AC potentiometry sensor, potential measurement probes, lead wires, a signal amplifier, the dual-trace oscilloscope, the A/D converter, a CCD image acquisition system and the computer. The invention is applicable to research on the fatigue crack propagation behavior of the alloy.
Description
Technical field
The present invention relates to fatigue of materials Performance Detection field, refer in particular to a kind of method and apparatus of reckoning fatigue crack propagation rate of flat alloy by AC potentiometry, mainly be applicable to the research of alloy fatigue crack propagation behavior.
Background technology
The antifatigue crack propagation performance of material becomes important parameter in the design of real member, for guaranteeing the requirement of member safe handling, need the fatigue and the crack propagation behavior of research material.Therefore function formula when adopting potential method to derive crack Propagation between potential difference (PD) and the crack length can be used to calculate FATIGUE CRACK GROWTH speed with potential difference (PD) as the function that characterizes crack position and dimensional parameters.The potential monitoring method is divided into dc-bit method (DCPD) and ac potential method (ACPD), and the ac potential method mainly is to be used for monitoring the conductive surface crackle to produce and spread scenarios.
During ac potential method monitoring crack Propagation, add alternating current and to member lasting alternating current is provided through a pair of current supply probe, the potential difference (PD) when a pair of current potential measuring probe is monitored the point-to-point transmission crack Propagation changes, and voltage table shows the respective electrical place value.Through monitoring and analysis potential difference signal, can draw the component surface fatigue crack and produce and spread scenarios, obtain crack propagation data such as fatigue crack growth rate at last.
Rapid crack is especially in the two-forty district, and crackle is tired to be expanded, and various noise in the expansion, and external environment is abominable in addition, brings many troubles for the surperficial crack Propagation of real-time monitoring.And the long-time auto-real-time monitoring crack Propagation of ac potential method ability is easy to operate, simple and easy, is suitable as the method for research material crack propagation behavior.
The patent that relates to the ac potential method both at home and abroad seldom; Application number is that 03128293.8 Chinese patent " detects the ground electrical measurement method of underground metallic conduit corrosion condition "; Utilize ac potential method principle to detect underground metallic conduit corrosion condition; It is characterized in that being the basis with ac potential method monitoring principle; Survey line along perpendicular to pipeline rout is arranged ground connection transmitting electrode and potential electrode; Potential electrode be connected with the wide spectrum electric pilot replace with principle in voltage table be connected, constantly change frequency with the wide spectrum electric pilot and carry out potential difference (PD) amplitude and phase measurement, confirm according to the size of the unusual amplitude of pipeline on the phase frequency spectral curve whether pipeline is corroded and is corroded degree again.This method needs constantly to change wide spectrum electric pilot frequency in detection, and automatism and blindness are bigger; Formula so that the theoretical formula of the amplitude of alternating electric field and phase place is the basis is more loaded down with trivial details, and calculated amount is big; And detect extent of corrosion with the ac potential method, other tired expansion is not related to, application surface is narrow, can not draw the overall process of corrosion fatigue expansion automatically.
Wang Liang
[1]Deng the people once inquired into dc-bit method under the high temperature measure the method for crack Propagation and use in solution ([1] Wang Liang of going wrong; Ding Chuanfu. dc-bit method is measured the application [J] of crack length under the high temperature. physical and chemical inspection-physics fascicle; 2006,42 (9): 454-456).This method and ac potential method measuring principle are similar; Different is that impressed current is a direct current; This method can record fatigue crack length, and the automaticity of raising, weak point are that this method is employed in the sample punching and embeds the potential measurement probe; Destroy the integrality of sample, be difficult to realize Non-Destructive Testing.
Summary of the invention
The objective of the invention is to diminish deficiencies such as sample integrality, the limitation of data integrity record, the restriction of monitoring various alloy sample crack Propagation environmental factors and the raising of system and device precision for overcoming potential measurement probe embedding sample; Design improved ac potential method sensor; Potential change during through the expansion of improvement potential measurement probe monitoring crackle two; Add the visual image of the online shooting specimen surface of CCD crack propagation, thereby propose a kind of method and apparatus of reckoning fatigue crack propagation rate of flat alloy by AC potentiometry.
The method that the present invention adopts is: the flat alloy sample that has precrack draws in the whole process of testing fatigue; Electric potential signal when the ac potential method sensor that is installed in the surface crack place is expanded through potential measurement probe on-line real time monitoring crackle two after amplifier amplifies, demonstrates two potential waveform figure in dual trace oscilloscope; The electric potential signal that monitors is stored in the computing machine at last; Through supporting integrated software, from computing machine, draw sample crack Propagation data such as fatigue crack growth rate etc., be the whole process of concrete statement crack Propagation; Adopt the ccd image acquisition system among the present invention; The record crack propagation process also deposits computing machine in, takes the situation directly perceived of crack Propagation from another angle comprehensively, avoids the careless omission of crack Propagation research details.
The device of implementing this method comprises fatigue tester and specimen holder, precrack flat alloy sample, ac potential method sensor, potential measurement probe, lead-in wire, signal amplifier, dual trace oscilloscope, A/D converter, ccd image acquisition system and has the computing machine of supporting integrated software.Induce coil to be installed in the surface of the flat alloy sample that has precrack together with two pairs of potential measurement probes in a pair of rectangle of ac potential method sensor; Two pairs of potential measurement probes are positioned at two of precrack and this crackle are contained in the centre position; Two of ac potential method sensor induce coil to lay respectively at tested alloy sample precrack two, surface and two pairs of potential measurement probes are comprised wherein; Integral body places on the fatigue tester, with anchor clamps the alloy sample two ends is fixed; Lead on the flat-top lid of one of them probe of every pair of potential measurement probe links to each other with the input end of a signal amplifier, and the lead on another flat-top lid then links to each other with the output terminal of dual trace oscilloscope; Be connected with two input ends of dual trace oscilloscope with the output terminal of lead with two signal amplifiers, the output terminal of dual trace oscilloscope then links to each other with the input end of A/D converter again, at last with the output terminal of A/D converter and the computing machine that has supporting integrated software.Ccd image acquisition system and fatigue tester also link to each other with this computing machine.
The potential measurement probe is made up of two parts, i.e. cylinder blanket and the flat-top lid that is embedded with lead.Cylinder blanket connects through middle snap lock; The conducting resinl of two pairs of cylindrical shapes on the flat alloy sample, moulding in precrack two head region; Entangle with the conducting resinl of cylinder blanket, continue again in these two pairs of cylinder blankets, to inject conducting resinl, let the conducting resinl of cylindrical shape and shell combine closely two pairs of cylindrical shapes; Make the potential measurement probe can be fixed in the measurement zone, cover the flat-top lid that is embedded with lead at last.
Cylinder blanket convenient disassembly, freedom, need not brokenly the ring sample integrality, reusable.The flat-top lid is designed to the flat-top shape, can guarantee that conducting resinl fills with shell, and the tinsel in the lead is applied in the shell simultaneously, guarantees best conductive effect.Cylinder blanket and flat deck roof are to be composited by two kinds of materials, and skin all adopts insulating material such as electro-insulating rubber to process, and can shield the interference of extraneous big resistance etc., and internal layer all adopts conductive material, is made of such as copper, and guarantees good conductivity.The potential measurement probe of design can be fixed on crack Propagation measurement zone monitoring potential change like this; Need not destroy sample yet; As embedding probe etc. to sample punching, and the interference of the design of insulation can avoid extraneous high resistance object that fatigue crack is monitored the time.
Two of ac potential method sensor induce coil to lay respectively at tested alloy sample precrack two, surface and two pairs of potential measurement probes are comprised wherein; With induce coil by rectangle around to 22mm-25mm height; The long 55mm-59mm of this rectangle, wide 25mm-29mm, Δ=35-39mm.The extrinsic motivated electric current flows in this inducing coil, and the electric field of variation produces induced magnetic field, between two pairs of potential measurement probes, induces the generation induced current, impressed current is provided for this sensor.The coil of inducing in this improved ac potential method gathers the local test scope with induced current, and electric current diffusion diminishes, and it is just clear relatively to monitor potential value, precision improvement.
The method concrete steps of reckoning fatigue crack propagation rate of flat alloy by AC potentiometry are following:
(6) two head region of the precrack on the flat alloy sample are installed two pairs of potential measurement probes; Precrack is contained in the centre position; Again crackle two around on induce coil to form ac potential method sensor; Integral body places on the fatigue tester; The extrinsic motivated electric current flows in inducing coil, and the lead on one of them flat-top lid of every pair of potential measurement probe is linked to each other with a signal amplifier, and the lead on another flat-top lid then is connected with the output terminal of dual trace oscilloscope; The signal amplifier that links together with lead in the open system again, dual trace oscilloscope, A/D converter, ccd image acquisition system and have the devices such as computing machine of supporting integrated software, and make fatigue tester in running order.
(7) signal of crackle two potential change of causing through two pairs of potential measurement probe on-line real time monitoring crack Propagation of ac potential method sensor.
(8) two signal amplifiers amplify crackle two potential change signal that two pairs of potential measurement probes monitor, be sent in the dual trace oscilloscope, the potential data when showing the expansion of crackle two simultaneously through dual trace oscilloscope with can survey oscillogram.
(9) in two A/D converters inputs of electric signal warp computing machines that above-mentioned dual trace oscilloscope is collected, potential data draws crack propagation data such as fatigue crack growth rate through Computer Processing.Computer software is the basis with the potential change of Johnson derivation and the functional relation between the crack Propagation parameter.
(10) CCD is used for taking the image of whole Fatigue Cracks Propagation, and recorded information also is stored in the computing machine that contains software kit, avoids the careless omission of crack Propagation research details, carries out subsequent use to the subsequent treatment of crack Propagation.
The present invention compares with existing potential method monitoring crack Propagation, has following advantage:
(1) the potential measurement probe that designs among the present invention promptly possesses the effect of transmitting alternating current, can completely cut off extraneous possible high resistance again and disturb.This probe is made up of two parts, and promptly cylinder blanket and flat deck roof are sub, and cylinder blanket is formed by two kinds of material sortings, and inner layer material has higher conductive capability, and skin has shielding action, can freely open, and is convenient to repeatedly use; Flat-top cover design, purpose are that the cylindrical shell therewith that the conducting resinl of inside injection is moulded meets fully, improve electrical efficiency.
(2) among the present invention general ac potential method is improved; Adopt the Theory of Electromagnetic Field of " magnetoelectricity interpromoting relation in five elements ", excite magnetic field, produce induced current in the area monitoring zone with exciting current; Compare with general ac potential method; This induced current is dispersed few, can accumulate in the monitored area, has improved the precision of monitoring electric potential signal.
(3) two pairs of potential measurement probes are set at crackle two; And electric potential signal during with the sample two crack Propagation that monitors; After amplifier amplifies; Deliver to dual trace oscilloscope, so not only can read the size of electric potential signal simultaneously, more can intuitively demonstrate the oscillogram of the electric potential signal that these two pairs of potential measurement probes monitor.
(4) alloy specimen surface place crack Propagation is adopted the ccd image acquisition system; Can take the spread scenarios of alloy sample surface fatigue crackle in real time; Software through supporting design in this system; Can carry out follow-up study to surperficial crack Propagation and handle, from many aspects, multi-angle understands crack Propagation, is difficult for the details of the important crack Propagation of carelessness.
(5) fatigue tester Control Software, crack Propagation analysis software and ccd image acquisition system integrated software system are housed in the computing machine.The crack Propagation analysis software is the basis with the funtcional relationship between Johnson current potential and the crack Propagation parameter, can onlinely draw tired growth daties such as fatigue crack growth rate and comprise numerical value and diagram.
Description of drawings
Fig. 1 is the closed control system synoptic diagram of reckoning fatigue crack propagation rate of flat alloy by AC potentiometry.
Fig. 2 is the synoptic diagram of device at the ac potential method sensor (4) at alloy sample surface crack place.
Fig. 3 is ac potential method sensor (4) the system and device three-view diagram that places alloy sample surface crack place.
Fig. 4 is potential measurement probe (a 6) structural design drawing.
Fig. 5 is embedded with the flat-top lid (17) of lead-in wire (7) for potential measurement probe (6)
Fig. 6 is probe (6) cylinder blanket (18) structural drawing of monitoring electric potential signal.
Ccd image acquisition system (12) diagram of Fig. 7 for specimen surface place crack Propagation is taken in real time
Fig. 8 is computing machine (11) synoptic diagram that fatigue tester Control Software, crack Propagation analysis software and ccd image acquisition system software are installed.
Among the figure, 1. fatigue tester 2. specimen holders 3. flat alloy samples 4. ac potential method sensors 5. prepared surface crackles 6. potential measurement probes 7. leads 8. signal amplifiers 9. dual trace oscilloscope 10.A/D converters 11. computing machine 12.CCD image capturing systems 13. are induced coil 14. exciting currents 15. induced currents 16. induced magnetic fields 17. flat-top lids 18. cylinder blankets 19. tinsels 20. snap locks.
Embodiment
Specify the details and the working condition of the concrete device of the present invention's proposition below in conjunction with accompanying drawing.
The device that carries out reckoning fatigue crack propagation rate of flat alloy by AC potentiometry with the present invention comprise fatigue tester (1), specimen holder (2) and between dull and stereotyped sample (3), sample on the computing machine (11) of the ac potential method sensor (4), prepared surface crackle (5), potential measurement probe (6), lead-in wire (7), signal amplifier (8), dual trace oscilloscope (9), A/D converter (10), ccd image acquisition system (12) and the installation software kit control program that install.
Fig. 1 is the closed control system synoptic diagram of reckoning fatigue crack propagation rate of flat alloy by AC potentiometry.At first be installed in the sensor (4) that is the basis with ac potential method principle on this sample (3), integral body places on the fatigue tester (1) afterwards, and sample all is in the testing fatigue state that draws in the whole observation process.Ac potential method sensor (4) on the one hand to sample provide ability of aggregation higher add alternating current (15); Two pairs of potential measurement probes (6) of settling of matching surface crackle (5) two on the other hand; Every pair of potential measurement probe (6) all is contained in the centre position with crackle (5), monitors the variation of the crackle both sides current potential that crack Propagation causes in real time, these two pairs of electrode catheters monitorings (6) to current potential amplify through two amplifiers (8) respectively; Be resent in the dual trace oscilloscope (9); Can show the potential waveform figure that crackle two is expanded simultaneously through this oscillograph (9), through A/D converter (10), in the input computing machine (11); Carry out the processing of crack Propagation aspect data, can draw crack propagation data such as fatigue crack growth rate.CCD (12) is used for taking the image of whole Fatigue Cracks Propagation; Its image recording and fatigue tester (1) load loads and also controls and store through this computing machine (11); Subsequent treatment to crack Propagation is carried out place mat, thereby forms a closed control system of monitoring crack Propagation in real time.
Fig. 2 is the synoptic diagram of device at the ac potential method sensor (4) at alloy sample surface crack place.Build a pair of rectangle on tested alloy sample surface and induce coil (13), induce coil by rectangle around to 22mm-25mm height, the long 55mm-59mm of this rectangle, wide 25mm-29mm, the centreline spacing Δ=35-39mm of two rectangles.Extrinsic motivated electric current (14) flows in this inducing coil, and the electric field of variation produces induced magnetic field (16), can judge the direction of this induced magnetic field according to the right-hand rule and the direction of inducing the coil current loop, and like Fig. 2, the induced magnetic field direction is perpendicular to specimen surface.The magnetic field that changes produces electric field, in the middle of inducing coil, produces the strong induced current (15) of aggregation at this thus.
Fig. 3 is ac potential method sensor (4) the system and device three-view diagram of device at alloy sample surface crack place.The picture left above is the vertical view of improved ac potential law technology, and left figure below is a side view with right figure.General ac potential method is improved; On tested sample, build a pair of rectangle and induce coil (13); A=25mm-29mm, b=55mm-59mm, c=22mm-25mm, h=5～12mm, H=0mm; Feed exciting current (14) to this to inducing coil, make in the middle of two coils, to induce to produce induced current (15), and this induced current flows through crackle and is equivalent in the above-mentioned synoptic diagram 2 directly to add alternating current with what lead was introduced; Induced current in this improved ac potential method is not directly to introduce with lead, but induces generation.This improved ac potential law technology is more much bigger than the potential value that general potential method technical monitoring arrives; Especially the monitoring of counter stress CC expansion; Its potential value that monitors is bigger tens times than general potential method, and its precision is also higher than general potential method technology.The electric current that uses in improved ac potential method and the general potential method is compared, because induce coil that induced current is gathered the local test scope, the electric current diffusion diminishes, and it is just clear relatively to monitor potential value, precision improvement.It is thus clear that the ac potential method among the present invention can also be used to monitoring surperficial fatigue crack depth direction spread scenarios.
Fig. 4 is potential measurement probe (a 6) structural design drawing.This probe is made up of two parts, i.e. cylinder blanket (18) and be embedded with the flat-top lid (17) of lead.The conducting resinl of two pairs of cylindrical shapes in last precrack (5) two head region of flat alloy sample (3), moulding; Entangle with the conducting resinl of cylinder blanket (18) two pairs of cylindrical shapes; Continue in these two pairs of cylinder blankets (18), to inject conducting resinl again; Let the conducting resinl and the shell (18) of cylindrical shape combine closely, make potential measurement probe (6) can be fixed in the measurement zone, cover the flat-top lid (17) that is embedded with lead at last; Distance between a pair of current potential measuring probe (6) is 5mm～12mm.Conducting resinl can be selected the silver-plated conductive rubber of copper etc. for use.The potential measurement probe (6) of design can be fixed on crack Propagation measurement zone monitoring potential change like this; Need not destroy sample (3) yet; As embedding probe etc. to sample punching, and the interference of the design of insulation can avoid extraneous high resistance object that fatigue crack is monitored the time.
Fig. 5 is embedded with the flat-top lid (17) of lead-in wire (7) for potential measurement probe (6).Flat-top lid (17) is composited by two kinds of materials, and the outer insulating material that adopts is made like electro-insulating rubber; Internal layer adopts conductive material; Do like copper, why like this design is filled with this potential measurement probe case (18) because can guarantee conducting resinl; Tinsel (19) in the lead-in wire (7) is applied in the potential measurement probe case (18) simultaneously, guarantees best conductive effect.
Fig. 6 is probe (6) cylinder blanket (18) structural drawing of monitoring electric potential signal.Cylinder blanket (18) connects through middle snap lock (20), entangles the conducting resinl of going up two pairs of cylindrical shapes moulding in precrack (5) two head region at flat alloy sample (3).Shell (18) convenient disassembly, freedom, need not brokenly the ring sample integrality, reusable; Be composited by two kinds of materials, outer insulating material such as the electro-insulating rubber of adopting processed, and can shield external world's interference of resistance etc. greatly; Internal layer adopts conductive material, is made of such as copper, and guarantees good conductivity.
Ccd image acquisition system (12) diagram of Fig. 7 for specimen surface place crack Propagation is taken in real time.This system comprises camera system and storage system; Camera system is made up of two parts again; It is the image importation that optical microscope, CCD camera and video frequency collection card are formed; Also have this image output of high resolution display, the computing machine among Fig. 1 (11) can be used as image storage, processing and analytical equipment.Wherein the CCD camera need be used under the pulsed laser pulse action and drive, and forms vision signal.Video frequency collection card is then imported the vision signal of camera collection in the computing machine, and this is installed with A/D converter and image displaying circuit, can import dynamic image and material object rapidly.The image that the high resolution display output device can will be handled whole flow process shows fast, links to each other with input equipment.
Fig. 8 is computing machine (11) synoptic diagram that fatigue tester Control Software, crack Propagation analysis software and ccd image acquisition system software are installed.The crack Propagation analysis software is the basis with the current potential of Johnson derivation and the functional relation between the crack Propagation parameter; The fatigue crack growth rate data be can onlinely draw and numerical value and diagram comprised; The data that also have the torture test of various national standard sample; Can be regarded as making this invention have purpose and comparability with reference to the contrast object.
Ac potential method sensor in real time monitoring crack Propagation electric potential signal; Draw parameters such as fatigue crack growth rate through software processing; The online shooting crack Propagation of ccd image acquisition system dynamic image, multi-angle overall understanding crack Propagation situation.
Claims (4)
1. the device of reckoning fatigue crack propagation rate of flat alloy by AC potentiometry; It is characterized in that, comprise fatigue tester (1) and specimen holder (2), ac potential method sensor (4), potential measurement probe (6), lead (7), signal amplifier (8), dual trace oscilloscope (9), A/D converter (10), ccd image acquisition system (12) and computing machine (11); The a pair of rectangle of said ac potential method sensor (4) induces coil (13) and two pairs of described potential measurement probes (6) to be installed in the surface of the flat alloy sample (3) that has precrack; Two tops that said two pairs of potential measurement probes (6) are positioned at the precrack of alloy sample (3) are contained in the centre position with this crackle; Induce coil (13) to lay respectively at two tops of the surperficial precrack of tested alloy sample (3) and two pairs of potential measurement probes (6) are comprised wherein for said two, alloy sample (3) places on the fatigue tester (1); The lead (7) of one of them probe of every pair of potential measurement probe (6) links to each other with the input end of a signal amplifier (8), and the lead of another probe (7) then links to each other with the output terminal of dual trace oscilloscope (9); The output terminal of two said signal amplifiers (8) is connected with two input ends of dual trace oscilloscope (9) through lead (7); The output terminal of dual trace oscilloscope (9) links to each other with the input end of A/D converter (10) through lead (7), and the output terminal of A/D converter (10) links to each other with computing machine (11) through lead (7); Said ccd image acquisition system (12) links to each other with this computing machine (11) through lead (7) with fatigue tester (1); The crack Propagation analysis software that said computing machine (11) is installed is the basis with the potential change of Johnson derivation and the functional relation between the crack Propagation parameter.
2. the device of reckoning fatigue crack propagation rate of flat alloy by AC potentiometry according to claim 1; It is characterized in that; Said potential measurement probe (6) is made up of cylinder blanket (18) and flat deck roof (17); Said flat-top lid (17) is the flat-top shape, is embedded with lead, and the tinsel (19) in the said lead is applied in the cylinder blanket (18); Said cylinder blanket (18) can freely be opened, through snap lock (20) connection of centre; Said cylinder blanket (18) and flat deck roof (17) are to be composited by two kinds of materials, and skin all adopts insulating material, and internal layer all adopts conductive material to process.
3. the device of reckoning fatigue crack propagation rate of flat alloy by AC potentiometry according to claim 1 and 2; It is characterized in that; Two of said ac potential method sensor (4) induce coil (13) to press rectangle around to the 22mm-25mm height; The long 55mm-59mm of said rectangle, wide 25mm-29mm, the centreline spacing Δ=35-39mm of two said rectangles; To said coil (13) the extrinsic motivated electric current (14) of inducing, the electric field of variation produces induced magnetic field (16), between two pairs of potential measurement probes (6), induces to produce induced current (15), impressed current is provided for this sensor.
4. implement the method for the device of reckoning fatigue crack propagation rate of flat alloy by AC potentiometry according to claim 2, it is characterized in that, concrete steps are following:
(1) precrack two head region on flat alloy sample (3) are installed two pairs of potential measurement probes (6), and precrack is contained in the centre position, again crackle two around on induce coil (13) to form ac potential method sensor (4); The conducting resinl of two pairs of cylindrical shapes in last precrack (5) two head region of flat alloy sample (3), moulding; Entangle with the conducting resinl of cylinder blanket (18) two pairs of cylindrical shapes; Continue in these two pairs of cylinder blankets (18), to inject conducting resinl again; Let the conducting resinl and the shell (18) of cylindrical shape combine closely, make potential measurement probe (6) can be fixed in the measurement zone, cover the flat-top lid (17) that is embedded with lead at last; Integral body places on the fatigue tester (1); Extrinsic motivated electric current (14) flows in inducing coil (13); Lead on one of them flat-top lid (17) of every pair of potential measurement probe (6) is linked to each other with a signal amplifier (8); Lead on another flat-top lid (17) then is connected with the output terminal of dual trace oscilloscope (9), opens the device of described reckoning fatigue crack propagation rate of flat alloy by AC potentiometry;
(2) signal of crackle two potential change of causing of two pairs of potential measurement probes (6) the on-line real time monitoring crack Propagation through said ac potential method sensor (4);
(3) said two signal amplifiers (8) amplify crackle two potential change signal that two pairs of potential measurement probes (6) monitor; Be sent in the dual trace oscilloscope (9), the potential data that shows crackle two when expansion through dual trace oscilloscope (9) simultaneously with can survey oscillogram;
(4) in electric signal two A/D converters of warp (10) input computing machines (11) that said dual trace oscilloscope (9) is collected, potential data is handled through computing machine (11) and is drawn fatigue crack growth rate;
(5) said ccd image acquisition system (12) is used for taking the image of whole Fatigue Cracks Propagation; Recorded information also is stored in the computing machine (11) that contains software kit; Avoid the careless omission of crack Propagation research details, carry out subsequent use the subsequent treatment of crack Propagation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101661431A CN101832970B (en) | 2010-05-07 | 2010-05-07 | Device and method for reckoning fatigue crack propagation rate of flat alloy by AC potentiometry |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101661431A CN101832970B (en) | 2010-05-07 | 2010-05-07 | Device and method for reckoning fatigue crack propagation rate of flat alloy by AC potentiometry |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101832970A CN101832970A (en) | 2010-09-15 |
| CN101832970B true CN101832970B (en) | 2012-08-29 |
Family
ID=42717113
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010101661431A Expired - Fee Related CN101832970B (en) | 2010-05-07 | 2010-05-07 | Device and method for reckoning fatigue crack propagation rate of flat alloy by AC potentiometry |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101832970B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018093855A1 (en) * | 2016-11-16 | 2018-05-24 | 3M Innovative Properties Company | Verifying structural integrity of materials using magnetic field stimulation |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102565140A (en) * | 2012-02-20 | 2012-07-11 | 南京航空航天大学 | Method for measuring fatigue crack growth rate on basis of potential method |
| CN105203402B (en) * | 2015-11-03 | 2018-04-10 | 华北电力大学 | The device and method of pyrogenic steam oxidation and test for stress corrosion cracking is realized simultaneously |
| EP3542153A1 (en) | 2016-11-16 | 2019-09-25 | 3M Innovative Properties Company | Temperature-independent verifying of structural integrity of materials using electrical properties |
| WO2018093859A1 (en) | 2016-11-16 | 2018-05-24 | 3M Innovative Properties Company | Electrode placement for verifying structural integrity of materials |
| US11255807B2 (en) | 2016-11-16 | 2022-02-22 | 3M Innovative Properties Company | Verifying structural integrity of materials |
| US11060993B2 (en) | 2016-11-16 | 2021-07-13 | 3M Innovative Properties Company | Suppressing thermally induced voltages for verifying structural integrity of materials |
| WO2018140147A2 (en) | 2016-12-16 | 2018-08-02 | 3M Innovative Properties Company | Verifying structural integrity of materials |
| EP3555607A2 (en) | 2016-12-16 | 2019-10-23 | 3M Innovative Properties Company | Verifying structural integrity of materials |
| EP3555606B1 (en) | 2016-12-16 | 2022-08-17 | 3M Innovative Properties Company | Verifying structural integrity of materials using reference impedance |
| CN108680607B (en) * | 2018-08-30 | 2021-02-26 | 四川大学 | Pipeline crack corrosion monitoring method based on multidirectional alternating current potential drop |
| CN113533435B (en) * | 2021-06-28 | 2022-08-05 | 南京航空航天大学 | Curve crack propagation monitoring method combining potential method and replica method |
| CN113533074B (en) * | 2021-07-20 | 2022-09-27 | 华东理工大学 | Material high-temperature fatigue threshold value measuring system and crack length high-precision calibration method |
| CN115046872B (en) * | 2022-08-09 | 2022-11-15 | 南通泰胜蓝岛海洋工程有限公司 | Fatigue crack real-time measuring method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2161936A (en) * | 1984-06-20 | 1986-01-22 | Secr Defence | Alternating current potential drop crack detection |
| CN200982983Y (en) * | 2006-08-22 | 2007-11-28 | 陈镜逢 | Electric probe device |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2289338A (en) * | 1994-04-12 | 1995-11-15 | Unvala Ltd | Alternating current potential drop measurement |
| JPH11132988A (en) * | 1997-10-31 | 1999-05-21 | Mitsubishi Heavy Ind Ltd | Probe of gauge for measuring crack |
| GB0019434D0 (en) * | 2000-08-09 | 2000-09-27 | Rolls Royce Plc | A device and method for fatigue testing of materials |
| JP2005164438A (en) * | 2003-12-03 | 2005-06-23 | Tohoku Techno Arch Co Ltd | Nondestructive inspection apparatus using teleguidance type alternate potential |
-
2010
- 2010-05-07 CN CN2010101661431A patent/CN101832970B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2161936A (en) * | 1984-06-20 | 1986-01-22 | Secr Defence | Alternating current potential drop crack detection |
| CN200982983Y (en) * | 2006-08-22 | 2007-11-28 | 陈镜逢 | Electric probe device |
Non-Patent Citations (2)
| Title |
|---|
| JP特开2005-164438A 2005.06.23 |
| JP特开平11-132988A 1999.05.21 |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018093855A1 (en) * | 2016-11-16 | 2018-05-24 | 3M Innovative Properties Company | Verifying structural integrity of materials using magnetic field stimulation |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101832970A (en) | 2010-09-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101832970B (en) | Device and method for reckoning fatigue crack propagation rate of flat alloy by AC potentiometry | |
| JP5522699B2 (en) | Nondestructive inspection apparatus and nondestructive inspection method using pulse magnetism | |
| CN103163216B (en) | A kind of metallic conductor defect recognition based on giant magnetoresistance sensor and method of estimation | |
| Park et al. | Detection of the subsurface cracks in a stainless steel plate using pulsed eddy current | |
| CN205861611U (en) | A kind of detection arbitrarily moves towards the electromagnetism of crack defect and thermal imagery integrated detection device | |
| CN205720093U (en) | Metal pipeline corrosion data acquisition device | |
| CN103076376A (en) | Array electrode for testing corrosion states of metal and coated metal | |
| Ma et al. | Development of multiple frequency electromagnetic induction systems for steel flow visualization | |
| CN105866234B (en) | The ferromagnetic material nondestructive detecting instrument and method that current vortex and Barkhausen blend | |
| Morozov et al. | Comparison of PEC and SFEC NDE techniques | |
| CN108037178A (en) | A kind of Metal pipeline corrosion defects detection low frequency electromagnetic sensor array | |
| JP5935162B2 (en) | Damage evaluation method and damage detection device for high-strength fiber composite cable. | |
| CN212903306U (en) | Multi-physical quantity synchronous monitoring device for transformer | |
| CN204613151U (en) | A kind of compressed natural gas storage well the cannot-harm-detection device | |
| CN104568629B (en) | The sample and method of speed is thinned in a kind of on-line checking metal | |
| CN106443317A (en) | Transformer copper-clad aluminum winding detector and detection method | |
| US11169097B2 (en) | Device and method for harmonic electromagnetic spectroscopy | |
| Park et al. | Differential pulsed eddy current probe to detect the sub surface cracks in a stainless steel pipe | |
| CN203216901U (en) | Stress detecting device | |
| CN101581699B (en) | Pulse eddy nondestructive testing method based on time gate | |
| CN111751440B (en) | Steel defect internal and external magnetic disturbance comprehensive detection device and detection method | |
| Bernieri et al. | ECT probe improvement for in-service non-destructive testing on conductive materials | |
| Majidnia et al. | Investigation of an encircling Pulsed Eddy Current probe for corrosion detection | |
| Strapacova et al. | Material defect identification using sweep frequency eddy current technique | |
| Abrantes et al. | Embedded measurement system for non-destructive testing using new eddy currents planar array probe |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120829 Termination date: 20130507 |