CN101438150A - Ultrasonic test method and equipment for ceramic honeycomb structure - Google Patents
Ultrasonic test method and equipment for ceramic honeycomb structure Download PDFInfo
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- CN101438150A CN101438150A CNA2006800545990A CN200680054599A CN101438150A CN 101438150 A CN101438150 A CN 101438150A CN A2006800545990 A CNA2006800545990 A CN A2006800545990A CN 200680054599 A CN200680054599 A CN 200680054599A CN 101438150 A CN101438150 A CN 101438150A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
- B01D46/24—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
- B01D46/2403—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies characterised by the physical shape or structure of the filtering element
- B01D46/2418—Honeycomb filters
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
- B01D46/0084—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours provided with safety means
- B01D46/0086—Filter condition indicators
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2273/00—Operation of filters specially adapted for separating dispersed particles from gases or vapours
- B01D2273/18—Testing of filters, filter elements, sealings
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2279/00—Filters adapted for separating dispersed particles from gases or vapours specially modified for specific uses
- B01D2279/30—Filters adapted for separating dispersed particles from gases or vapours specially modified for specific uses for treatment of exhaust gases from IC Engines
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
- B01D46/24—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
- B01D46/2403—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies characterised by the physical shape or structure of the filtering element
- B01D46/2418—Honeycomb filters
- B01D46/2425—Honeycomb filters characterized by parameters related to the physical properties of the honeycomb structure material
- B01D46/2429—Honeycomb filters characterized by parameters related to the physical properties of the honeycomb structure material of the honeycomb walls or cells
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Abstract
A method and device for detecting the presence or absence of internal discontinuities or inhomogeneities in a fired or green ceramic honeycomb structure is provided. In the method, an ultrasonic transmitter (33) and receiver (35) are positioned on outer locations of the honeycomb structure, and the transmitter is actuated to generate an ultrasonic wave that is conducted through an inner portion of the honeycomb structure (40), and received by the ultrasonic receiver. The received ultrasonic wave is filtered and then analyzed to determine the presence of internal discontinuities (17). The transmitter generates ultrasonic waves having a frequency of five megahertz or less to maintain a high signal to noise ratio in the propagated wave received by the ultrasonic receiver. The device of the invention includes an array of ultrasonic transmitters and receivers which are simultaneously actuated as a ceramic substrate is moved relative thereto to quickly and efficiently provide a full, non-contact scan of the ceramic body for discontinuities.
Description
Technical field
The present invention relates generally to be used for detect the method for the inside uncontinuity of ceramic honeycomb structure, specifically, relate to a kind of supersonic ultrasonic testing method and equipment, it can be fast and determines whether there is inner uncontinuity in this structure effectively.
Background technology
Ceramic honeycomb structure is used to vehicle exhaust system, to reduce pollutant.This structure generally comprises netted Internet wall, and these walls have constituted the matrix of elongated air guide unit, and these unit can be for example square, octagons or hexagonal.Netted net wall is preferably surrounded by cylindrical crust, this crust is integrally connected to the outward flange of these net walls, to form jar shape structure or ellipsoidal structure, such structure has relative entrance and exit, so that receive waste gas and combustion gas by the matrix of these unit.
This ceramic honeycomb structure can be used as the particle filter in the exhaust system of diesel-powered car or other equipment or the catalytic converter of automobile.When being used as particle filter, preferably with the inlet end of this structure of " chessboard " mode jam-pack and the openend of the unit on the endpiece, the feasible waste gas that enters the inlet end of this structure must pass the ceramic network wall of porous, could allow them to discharge from the opening of the unit of the endpiece of this structure.When being used as catalytic converter, these unit keep the not state of jam-pack, make waste gas can directly flow through these unit, and these cell-wall all scribble noble metal catalyst, wherein comprise for example platinum, rhodium or palladium.After these net walls reached ignition (light-off) temperature, the catalyzer that is flooded on the net wall can make CO
2Oxidation, and make NO
xBe separated into N
2And O
2Two kinds of application of this of ceramic honeycomb structure all are important for reducing pollutant, have suffered otherwise these pollutants just are discharged into environment.
This ceramic structure preferably forms like this: by a mould, extrude the paste ceramic precursor of trichroite, mullite, silit or aluminium titanates, to form the crust that netted net wall and one connect simultaneously.The green ceramic bodies that gained is extruded is cut, dry and be moved in the stove, this stove converts green ceramic bodies to the ceramic body that burnt.Next, the ceramic body that burnt by above-mentioned pattern jam-pack perhaps carries out catalyst detergent to it and applies so that the wall of through-flow (flow-through) unit has flooded catalyzer with the formation diesel particulate filter.
Unfortunately, in the process of extruding, handling and fire, internal damage may occur within the ceramic substrate, this can diminish ceramic body and remove performance from the pollutant in the automobile exhaust system (this ceramic body finally just is installed in this system).This damage may comprise: along the crackle of this structure turning axle orientation; And with the crackle of this transverse intersection, be called as axial crack and " hoop (ring-off) " crackle hereinafter.In the mesh network wall of this structure and the local detachment between the crust, other damage is displayed.Finally, outside fine rule crackle may appear or other diminishes the cut and the distortion of intensity on this body structure surface.
In the prior art, known have some kinds to be used to test the method whether various manufacture component have uncontinuity.These methods comprise that X ray detects and CT scan.Yet it is insensitive that this X ray detects the underbead crack that may exist honeycomb ceramic structures inside, unless this defective is greater than a certain size.Even when this defective is large enough to can be detected the time, also must carefully check the fine detail of this radioscopic image, could distinguish this defective.Check that intactly a cellular structure may spend several hrs, this is oversize for actual manufacturing process.Other technology identical with the principle of X-ray examination (such as X ray layering Photographic technique and tomography art) also all has identical shortcoming, they need much longer time and much more effort, thereby can not effectively and reliably detect crackle and other uncontinuity in the time frame that is fit to actual manufacturing process.
Clearly, need a kind of method that is used to detect ceramic honeycomb structure, it can be fast and detect whether have that uncontinuities such as axial crack or " hoop " crackle, crust separate reliably, outside fine rule crackle or other distortion or fault, these defectives may seriously diminish the effect of ceramic structure in exhaust system.Ideally, this method be fast, non-invasion formula, and can include in well in the standard manufacture technology.Finally, expect that this method is applicable to green ceramics structure or the ceramic structure of firing, making can no longer need to fire defective green ceramic bodies when using this detection method, and the finished product of finishing, fire is carried out final inspection.
Summary of the invention
In general, the present invention is a kind of uncontinuity or heteropical method that is used for detecting fired or green ceramics cellular structure, and this method can be avoided or improve all defect be associated with the method for testing of prior art at least.For this reason, this method comprises the steps: ultrasonic transmitter is placed near first external position on the cellular structure; Ultrasonic receiver is placed near second external position on the cellular structure; Drive transmitter to produce ultrasound wave, the inside of cellular structure is passed in this ultrasound wave conduction; Pass the ultrasound wave that the cellular structure conduction is come in the reception of receiver place; Produce a response signal based on this ultrasound wave then.Next, remove the noise that appears in the response signal, it is analyzed to determine whether to exist inner uncontinuity or heterogeneity to produce filtered response signal.
Preferably, drive transmitter to produce the ultrasound wave less than about 5MHz, the ultrasound wave that makes conduction pass cellular structure has higher relatively signal to noise ratio (S/N ratio).More preferably, transmitter produce between about 150 and 700kHz between ultrasound wave, between 150 and 500kHz between then best.
Above-mentioned ultrasonic frequency is particularly useful for to tell observantly by the stupalith that is selected from trichroite, silit, mullite or aluminium titanates and is constituted uncontinuity in the ceramic honeycomb structure, the porosity rate of this structure is between 15% and 85%, and is then better between 20% and 45%.This method can be used for detecting axial crack or the circumferential crack within the netted net wall, also can be used for detecting the separation between net wall and the crust.This method also can detect surface scratch and distortion.
Ultrasonic transmitter can be positioned at positions different on the ceramic honeycomb structure or identical position with receiver.When transmitter and receiver were positioned at same position on the ceramic honeycomb structure, transmitter and receiver can comprise a kind of combined type ultrasonic transceiver, and the ultrasound wave that this structure is passed in conduction can be a kind of pulse echo.When ultrasonic receiver and transmitter were positioned at positions different on the cellular structure, they can be positioned at position respect to one another on the relative both sides of this structure, and the ultrasound wave that cellular structure is passed in conduction can be a kind of transmission ultrasound wave.
Ceramic honeycomb structure can be a kind of through-flow structure, and it has a plurality of air flues and substrate passageways, and the conduction ultrasound wave that passes cellular structure can pass air flue or passes substrate and conduct.When ceramic structure was green ceramic bodies, the air flue that ultrasound wave preferably passes this structure conducted.When ceramic structure was not fired, ultrasound wave preferably passed substrate passageways and conducts.
Ultrasonic transmitter and receiver can be oriented to contact with ceramic honeycomb structure, perhaps are positioned near the non-contacting position place of this structure outer wall.After filtered first response signal was analyzed, ultrasonic transmitter and receiver can be reorientated with respect to cellular structure, and drove once more, so that any inner uncontinuity or heterogeneity finally all are detected.If do not use the single ultrasonic transmitter and the receiver of reorientating in order, then can use arrayed ultrasonic transmitter and receiver to come more promptly " scanning " thus whole ceramic body determines whether to exist any uncontinuity or heterogeneity.In preferred approach of the present invention, the array of ultrasonic transmitter and receiver is positioned near the ceramic body outer wall but contact with it, so that can be rapidly and scan this ceramic body effectively and with detection whether defective is arranged.
The present invention also comprises a kind of equipment that is used to realize non-contact scanning method of the present invention, and this equipment comprises: array of ultrasonic transmitters is positioned near the cellular structure but contact with it; And the ultrasonic receiver array, it is relative with array of ultrasonic transmitters, is used to receive the ultrasound wave that passes this structure-borne.Array of ultrasonic transmitters and ultrasonic receiver array can be positioned to toward each other, and this equipment can comprise travelling belt or other device that is used for mobile ceramic honeycomb structure between these two arrays.Perhaps, the array of ultrasonic transmitter and receiver can comprise single ultrasonic transceiver array, this transceiver array emission and receive ultrasonic pulse when cellular structure moves with respect to transceiver array does not have uncontinuity or other heterogeneity so that define by the pulse echo technology.
Description of drawings
Figure 1A is the skeleton view of through-flow ceramic substrate of the catalyzer of prior art, and it has inner uncontinuity.
Figure 1B is the plane partial view (1/4 section) of the ceramic substrate of Figure 1A along the 1B-1B line.
Fig. 1 C is the part cross-sectional side view of the ceramic substrate of Figure 1A along the 1C-1C line.
Fig. 2 A is the synoptic diagram that contact transmission supersonic ultrasonic testing method of the present invention is applied to the through-flow ceramic substrate.
Fig. 2 B be the contact transmission embodiment of said method be applied to as particle filter by the synoptic diagram of the substrate of jam-pack.
Fig. 2 C be the pulse-echo embodiment of said method be applied to such as particle filter by the synoptic diagram of the ceramic substrate of jam-pack.
Fig. 3 A shows the synoptic diagram of principle of the transmission embodiment of method of the present invention.
Fig. 3 B and 3C show respectively and pass substrate that does not have inner uncontinuity and the substrate that inner uncontinuity is arranged and hyperacoustic amplitude of transmission.
Fig. 3 D shows and passes substrate with very big (stopping) inner uncontinuity and hyperacoustic amplitude of transmission.
Fig. 4 A shows the synoptic diagram of principle of the pulse echo embodiment of method of the present invention.
Fig. 4 B is the graphics track that illustrates at the amplitude time to time change of flawless diesel particulate filter substrate pulse echo.
Fig. 4 C is the curve map that illustrates at the amplitude time to time change of the diesel particulate filter pulse echo that crackle is arranged.
Fig. 5 A, 5B and 5C show " amplitude-time " curve map of the pulse echo that reflects respectively in the ceramic substrate with single crackle, two crackles and two crackles (wherein second crackle has been blocked).Fig. 6 A is the synoptic diagram of first embodiment of non-contact device of the present invention, and this device has the relative linear array of ultrasound emission and receiving transducer, is used to realize non-contact method of the present invention.
Fig. 6 B is the synoptic diagram of second embodiment of non-contact device of the present invention, and this device has the annular array of ultrasound emission and receiving transducer, is used to realize non-contact method of the present invention, and further shows the operation of present embodiment.
Fig. 6 C shows the variation that the amplitude of the ultrasonic signal that array produced of Fig. 6 B produces on the length X of the substrate that contains inner uncontinuity.
Fig. 7 is the synoptic diagram of the embodiment of non-contact testing device of the present invention, wherein two relative ultrasonic transducers simultaneously in the terminal enterprising line scanning of substrate to detect uncontinuity.
Fig. 8 is the partial cross section view of embodiment of the non-contact testing device of Fig. 7.
Fig. 9 A and 9B are the tracks that is used for signal that embodiment produces flow-through substrate, non-contact testing device shown in Figure 7.
Figure 10 A and 10B are the tracks that is used for signal that embodiment produces honeycomb filter, non-contact testing device shown in Figure 7.
Figure 11 and 12 is respectively the raster-scanned image according to the IR of each embodiment of non-contact test method and TOF image.
Embodiment
Now, with reference to Figure 1A, 1B and 1C, method and apparatus of the present invention is particularly suitable for detecting uncontinuity or other heterogeneity that may exist in the employed ceramic honeycomb structure 1 in diesel engine and the automobile exhaust system.This structure comprises the grid 3 of net wall 5, is used to limit the air guide unit 7 along the turning axle of structure 1.The grid 3 of net wall 5 is surrounded by crust 9.Crust 9 has inward flange 11, it generally integratedly (except at fault location) be connected to the outward flange of the grid 3 of net wall 5, Figure 1B provides the best and illustrates.The jar shape structure of gained has: inlet end 13 is used to receive the waste gas from diesel engine or car engine; And endpiece 15, be used to discharge these gases.
The ceramic honeycomb substrate 1 that is used as the through-flow catalyst substrate has wide-open unit 7 between inlet end 13 and endpiece 15.The density of unit 7 can be between about 100-900 unit/square inch.Cell density can maximize, and reaches maximum so that directly blow over the contact area of the automobile exhaust gas of air guide unit 7 and net wall 5.Fall in order to reduce the pressure that flow-through substrate 1 puts on the waste gas, net wall 5 is very thin usually, is the magnitude of 2-10 mil even 2-6 mil.
When this cellular structure 1 is used as wall-flow filter (such as diesel particulate filter), press the openend of the unit 7 at " chessboard " figure jam-pack inlet end 13 and endpiece 15 places, to force diesel exhaust gas to pass the net wall 5 of porous, come out from endpiece 15 again.Compare with the situation in the substrate that is used as catalytic characteristics, the density of unit 7 is lower, and promptly generally between about 100-400 unit/square inch, and net wall 5 is thicker usually, reaches the magnitude of 10-25 mil even 12-16 mil thick.Tubular construction 1 is not used as catalytic carrier or particle filter, and the thickness of crust 9 approximately is four times of net wall 5.
The plasticity pottery of extruding trichroite, mullite, silit or aluminium titanates by extrusion die forms precursor, just produces this structure 1.This " green ceramic bodies " extruded next is cut and is dry.This green ceramic bodies is quite frangible, must be transported in the stove, and heat is transformed into relative softer and frangible green ceramic bodies the fired honeycomb ceramics of sclerosis.
Unfortunately, expressing technique and the frangible green ceramic bodies of gained is carried out follow-up essential processing (comprise cutting and fire) all may cause structure 1 inside uncontinuity and heterogeneity 17 to occur.After even green ceramic bodies is fired, relatively thin crisp wall also might break because of physical shock and pressure in the cellular structure.This uncontinuity 17 can comprise: circumferential crack 19, the turning axle lateral cross of its orientation and structure 1; And axial crack 21, its orientation is parallel to this axle.In addition, between the inward flange 11 of the outward flange of the grid 3 of net wall 5 and crust 9, may occur separating 23.When the structure 1 of gained was used as particle filter, this uncontinuity 17 can make waste gas flow through structure 1 fully and not filter.When structure 1 was used as catalyst support, this uncontinuity 17 had formed local quick flow region, and this can make the pollutant in the waste gas that catalytic decomposition does not take place.Heterogeneity comprises: change in size (with the inner wall thickness of substrate, wall orientation and/or the relevant physical dimension of ripple); And microstructure change, such as the variation of the amount of the variation of the density variation in this structure, porosity rate and micro-crack.
Fig. 2 A shows first embodiment of method of the present invention, and this method is applied to through-flow ceramic structure 25, and its unit 7 defines the air duct 27 that has opening 29a, 29b at the inlet end 13 of this structure and endpiece 15 places.This pattern is called as " contact transmission " method in this article.In this embodiment of the invention, the emission ultrasonic signal makes it to be passed in the net wall 5 that extends between inlet end 13 and the endpiece 15.For this reason, test ultrasonic device 32 is provided with: transmitting transducer 33 is used to launch ultrasound wave 34 (being represented by wavy arrow); And receiving transducer 35, be used to receive these ripples 34.In this embodiment of the invention, transmit and receive transducer 33,35 and keep relative relation, and contact with structure 25, and on the inlet end 13 of structure 25 and endpiece 15, periodically reorientate and drive again, so that receiving transducer 35 periodically receives directly ultrasonic waves transmitted 34 from transmitting transducer 33.Each time, transducer 33,35 is all directly aimed at across this structure basically each other.Transmitting and receiving transducer 33,35 can be piezoelectric transducer well known in the art.Reception piezoelectric transducer 35 is resonance in response to the ultrasonic signal 34 of emission from transmitting transducer 33, and this makes it produce an electric signal.This signal transfers to be conducted to digital processing unit 37.Digital processing unit 37 filters by the noise in the received signal 34 of receiving transducer 35 (this noise is that ultrasound wave 34 repeatedly reflects between transducer 33,35 and causes), and the signal after will filtering sends to display 39.Perhaps, also can use other suitable ultrasonic testing transducer.
The array output that transmits and receives transducer has produced a kind of in the diameter of substrate 25 or the linear sweep on the string.When substrate 25 is flow-through substrate shown in Fig. 2 A, transducer 33,35 can transmitting transducer 33 be located immediately at one of longitudinal network wall 5 above the time be driven so that ripple 34 is passed substrate self by conduction.
Preferably, the frequency of the ultrasound wave 34 that produced of transmitting transducer 33 is less than about 5MHz.More preferably, be used to contact transmission method ultrashort wave (USW) 34 frequency between about 150 and 700KHz between, between 150 and 500KHz between best.The applicant finds that when producing ultrasound wave 34 in these scopes, it is maximum that signal to noise ratio (S/N ratio) reaches.As a comparison, when using the ultrasonic radiation of higher frequency, the applicant finds, be used to form substrate 25 material intrinsic porosity rate make and be difficult to the uncontinuity 17 that (if not impossible words) differentiate structure 1 inside that this is to cause because of very big noise factor.
Fig. 2 B shows the contact method that is applied to the ceramic substrate 40 of filter type of the present invention.This substrate 40 has the end plug 42 of an end that is positioned at each air guide unit 7, to limit the passage 43 of jam-pack.Previous the operation described pattern also can here be used.Equally, in this AD HOC of the present invention, transmit and receive transducer 33,35 and keep relative relation, and reorientate according to priority, and drive according to priority, so that produce a series of linear sweeps of substrate 40 along the diameter or the string of substrate 40.
Fig. 2 C shows the alternate embodiment of the inventive method, and wherein system 32 comprises and transmits and receives transducer, and they are used in the single ultrasonic transceiver 45, and hyperacoustic reflection echo is detected.This pattern is called as " pulse echo " method in this article.This specific implementations of said method is operated in " sonar " mode, and wherein the ultrasound wave that produced of transceiver 45 is reflected at the opposite end of substrate 40 and rebounds.In this specific implementations of said method, used transmission process, wherein transmitted wave 34 and reflection wave 47 pass the longitudinal network wall 5 of substrate 40 and transmission.In the present embodiment of said method, ultrasonic transceiver 45 is placed at inlet end 13 and endpiece 15 places and contacts with structure 40, and reorientate according to priority and drive again according to the mode identical, so that be achieved at the diameter of substrate 40 or the operation of the enterprising line scanning of string with method shown in Fig. 2 A and the 2B.By using this pulse echo methods, use echo just can detect and locate uncontinuity and/or heterogeneity 17 (such as underbead crack) through reflection.In addition, inner homogeneity also can be detected.This pulse echo methods can be applicable to comprise as shown in the figure the filtrator 40 of stopper 42 equally, but also can be used for detecting uncontinuity and heterogeneity 17 in the flow-through substrate.
(the model EPOCH 4 PLUS series of making such as the Panametrics-NDT company of State of Massachusetts, US Waltham) can be equipped and realized to method shown in Fig. 2 A, 2B and the 2C by commercially availabie ultrasonic tesint.Use the gain of 20-80dB (being preferably 40-60dB) and between the filtrator setting that (is preferably 300KHz) between about 100KHz and the 1MHz between the 800KHz.Transmitter and receiver be the barrier film transducer or the drying-couplant transducer of protectiveness preferably.This transducer can have surface or the flexible barrier film of complying with, and it is configured to contact with substrate.Randomly, barrier film can be placed in contact with the substrate, and can apply gel between barrier film and employed standard ultrasonic transducer.
Fig. 3 A-3C shows the contact transmission embodiment of method shown in Fig. 2 A-2B and how to operate.Particularly, Fig. 3 B is the curve map of the amplitude of the ultrasound wave 34 that substrate 1 is passed in transmission along its length when not having uncontinuity.As shown in Figure 3A, when driving transmitting transducer 33 with generation ultrasound wave 34, this transmission ultrasonic wave passes the whole length of substrate 1.Therefore, receiving transducer 35 just writes down higher relatively amplitude pulse 36A, 36B (Fig. 3 B) when receiving the ripple 34 of slightly decay.As a comparison, when when transmitting and receiving path between transducer 33 and 35 and have crackle or uncontinuity, this track has produced one or more peak value 36C, 36D by the mode of time grate.When having significant crackle or uncontinuity in the substrate 1, shown in Fig. 3 D, receiving transducer 35 does not receive or writes down hyperacoustic high amplitude pulse.On the contrary, the electric signal 36E that produced of receiving transducer 35 still keeps illustrated smooth.Therefore, the flat line in this track is illustrated in significant underbead crack or other defective within the position substrate of being tested 1.Certainly, by testing again in many other positions, can be altogether with the image sets of testing at every turn, thus spatial image about any existing defective is provided.
Fig. 4 A-4C shows the pulse echo embodiment of method shown in Figure 2 and how to operate.When ultrasonic transceiver 45 produced ultrasonic pulses 34, it passed the net wall from inlet end 13 transmissions of substrate 1, and wherein its substrate-air interface place of being limited at endpiece 15 is reflected.If there is not uncontinuity (such as crackle) in the path of ultrasound wave 34, then transceiver 45 received unique reflection waves 47 are exactly the ripple that rear wall reflected away of the substrate that limited by endpiece 15 in this example.Fig. 4 B shows the amplitude of the signal that receives and the graphics track of time under the situation of obviously not breaking.Particularly, within time grate 48, there is not tangible peak value.Yet, when in the path of ultrasound wave or pulse 34, having underbead crack or other uncontinuity 19, produced extra spike 20 in the track of ripple 47 within time grate 48 that is reflected, just as shown in Fig. 4 C.Specifically, the ripple 47 that is reflected produces and is positioned near the rear wall spike 49A in this figure end, and it comes from the ultrasonic echo of the rear wall place reflection of cellular structure; Also produce the main bang spike 49B that is positioned at this figure left side, the reflection case at these signal indication inlet face 13 places.An advantage of this pulse echo embodiment of the present invention is to determine the position of crackle 19 along the turning axle of cylindrical base 1 basically.The relative position of defective 19 is to determine by the relative position of the peak value within the time grate 48 20.When circumferential crack or uncontinuity were enough big, it can stop the ultrasound wave of incident fully.In this case, the ripple 47 that is reflected may only produce the echo from crackle, and do not have " rear wall " thus the amplitude of echo rear wall peak value 49A will be on the magnitude of ground unrest.
Fig. 5 A, 5B and 5C schematically show the pulse echo signature that is associated with the uncontinuity of the crackle of the different pattern that may exist or other type in the ceramic honeycomb substrate 1.Fig. 5 A is the schematic equivalent of pulse echo signature shown in Fig. 4 C, is wherein producing single spike 20 respectively on the left of this figure and between " main bang " the pulse 49B of the ultrasonic transducer 45 at place, right side and the rear wall echo-pulse 49A.Single crackle 19 in its expression honeycomb substrate 1.Fig. 5 B shows two different crackle 19a, 19b and how to produce two different spiking 20a, 20b, and these two crackles are not in alignment with each other along the turning axle of ceramic honeycomb substrate 1.The relative amplitude of these peak values is represented the relative size of these two crackle 19a, 19b.In addition, sonar principle not only can be used for determining crackle 20a and the 20b relative position along this, can also determine their absolute position.Their position is relevant to the relative position of peak value 49A, 49B with peak value 20a, 20b.Finally, Fig. 5 C shows: covered under the rare cases of less relatively crackle 19d along the axle of honeycomb substrate 1 at relatively large crackle 19c, the performance plot of big crackle can cover the performance plot than crackle 19d.Usually, this blocking is not problem in practice, because the existence of single sizable uncontinuity just is enough to this substrate is abandoned in the quality control testing process.Yet, if must avoid this covering of not expecting to have, by promptly substrate 1 just being scanned and can realize this point from the other end along two axles (but not only an axle).
Fig. 6 A shows first embodiment 50 of device of the present invention, and it can be used to realize non-contact method of the present invention.This method and apparatus is designed to scan apace with a kind of non-contact method the entire cross section of ceramic honeycomb substrate 1, to seek inherent vice or unevenness.This device 50 comprises the battle array column or row 52 of transmitting transducer 33, and they are with respect to the battle array column or row 54 and arranging with relativeness of receiving transducer 35.In operation, relative moving arranged between the top of ceramic honeycomb substrate and reception and transmitting transducer and bottom array 52,54, simultaneously, the top delegation 52 of transducer transmitter periodically and side by side launches pulsed ultrasonic wave 34.For the configuration of Fig. 6 A, above-mentioned relatively moving carried out on the direction of turnover paper by the mode that increases progressively gradually, wherein all produces a new pulse at increasing progressively each time in this scanning.Receiver capable 54 receives these ripples, and converts them to electric signal, and this electric signal transfers to be conducted to digital processing unit 37.Processor 37 transfers to produce a plurality of parallel figure, and they produce the complete scan of honeycomb substrate 1 jointly on its entire cross section, and they can be displayed on the monitor 39 then.In preferred implementation, by the travelling belt (not shown), ceramic substrate 1 can be with respect to the row 52,54 of transducer transmitter and receiver and is moved.The array of transmitter 52,54 is so the biggest as the width of honeycomb substrate 1, so that the inswept suitable complete screening that once just can provide about this substrate.Certainly, after inswept each time,, just can use littler array to provide complete scanning to cover through reorientating.
Fig. 6 B shows second embodiment 60 of device of the present invention, it is used to realize the noncontact embodiment of the inventive method, and the array that comprises transducer 61, these transducers are located radially outwardly from the skin 9 of the periphery of honeycomb substrate 1, and preferably arrange by circular pattern.Preferably along semicircle 62,64 location, array 61 can comprise four transducer transmitter 33 and four transducer receivers 35 of for example arranging in couples in relative mode to array 61.Preferably, transmitter 33 is arranged in 62, four receivers 35 of first semicircle and is arranged in second semicircle 64.The electric input and output of transducer array 61 are connected to processor and display, and for the purpose of simplifying, they do not illustrate in Fig. 5 B.In operating process, by shown in travelling belt 66, mobile ceramic honeycomb substrate 1 makes it pass array 61, so that diameter scans its circumference on the whole length X of honeycomb substrate 1, to determine whether to exist inner uncontinuity 17 (separating 23) such as circumferential crack 19, axial crack 21 and/or skin.Certainly, according to the size of honeycomb substrate 1 or the resolution of wanting, can increase or reduce the right number of above-mentioned transducer.This method and apparatus can be used for also checking dry green honeycomb that such as honeycomb fashion round log structure, it comprises two sections or the uncut cellular structure of multistage.
Fig. 6 C schematically shows the combined type output of transducer array 61 with respect to the longitudinal axis of honeycomb substrate 1.C at this figure
1Section, that part that contains axial crack 21 in the honeycomb substrate 1 is placed within the transducer array 61, and the combined amplitude of the ultrasonic signal that makes this array thus and produced decays.This amplitude rise to once more the expression normal internal structure the top baseline, up to transducer array 61 be placed in circumferential crack 19 separate with skin 23 around.Shown in Fig. 6 C, when this array alignd with circumferential crack 19, the combined amplitude of the signal of being launched by transducer array 61 dropped on zone C
2In, and further drop on zone C
2+ C
3In, wherein transducer array 61 limits circumferential crack 19 simultaneously and separates 23 with skin.When this array was configured to only separate 23 around skin, amplitude rose to zone C once more
3In, next,, then return to its normal baseline so that the balance of the axial length X of substrate in case Annular Transducer array 61 is crossed the end of skin separation 23.
Fig. 7 schematically shows the 3rd embodiment 69 of device of the present invention, and this device is used to realize non-contact method of the present invention.In present embodiment 69, honeycomb substrate 1 is installed on the suitable stationary platform 65, and it can comprise two guide rails or other suitable anchor clamps, makes that input face 13 and output face 15 are exposed.Transducer transmitter 33 and transducer receiver 35 are positioned at the opposite place, two ends of cellular structure 1, and adjacent with output face 15 with input face 13.Transducer should be arranged near substrate 1, preferably near end 13,15.Spacing between transducer 33,35 and the substrate 1 is preferably between about 1/2 inch (about 13mm) and 2 inches (about 51mm). Transducer 33,35 can be installed on the mechanical support system 66, and they keep relative position each other.Mechanical support system 66 can be connected to translational worktable 67, these worktable control transducer 33,35 positions along X and Y coordinates.By driving translational worktable 67, transducer 33,35 is moved along X-axis by the speed of about 0.01-0.1 inch per second (0.025-2.5mm/s) and the increment of about 0.03-0.1 inch (0.76-2.5mm), just can carry out raster scanning to translational worktable 67 from predetermined reference position.After transducer 33,35 has advanced one section distance more than or equal to the diameter of honeycomb substrate 1, translational worktable 67 is advanced by the increment of about 0.03-0.1 inch (0.76-2.5mm), and repeat process mobile on X-axis.This process continues, and all is scanned up to whole 13,15 of honeycomb substrate 1.The length of X and Y is increasing progressively, and movable workbench speed depends on required resolution.
With reference to Fig. 8, the method for operating of the device of Fig. 6 A of being used for flow-through substrate and Fig. 7 has been described.In operating process, transducer 33 sends to ultrasound wave among the air gap 26a between honeycomb substrate 25 and the transducing 33, and this ultrasound wave enters substrate 25 then.This hyperacoustic test frequency can be 100KHz-1MHz, preferably 150-700KHz.Because the cause of the cellular structure of substrate 25, so two paths are arranged, one passes the air in the air duct 27, and another passes substrate wall 5.Because in the air in the passage 27 with to compare the velocity of sound be (THE VELOCITY OF SOUND IN AIR is about 340m/s) that differs widely in the axial substrate wall 5, so processor 37 can be programmed to have a kind of " door " that locks in time domain, to distinguish above-mentioned two paths (pass air 34 and pass substrate wall 34 ') thus check this substrate.Fig. 9 A is illustrated in (do not have substrate in the proving installation) in open air signal amplitude and the gained track of time, and demonstrates DTA peak value 70, and this peak value has reacted the scope (Fig. 8) of the distance L between above-mentioned two transducers 33,35.The flight time (TOF) that is used for the DTA peak value is provided by following formula:
TOF
DTA=L/C
Air
C wherein
AirBe the aerial speed of sound.
Fig. 9 B shows signal amplitude and the gained track of time under the situation that substrate is arranged in proving installation.The distance H of Fig. 8 is the corresponding height of substrate 25.In the track of Fig. 9 B, modulated DTA peak value 72 and DTS peak value 74 have been shown.The DTA peak value 72 that reduces has the amplitude that reduces, and (Fig. 9 A) appears in still common and peak value 70 simultaneously.The flight time of DTS peak value 74, (TOF) provided by following formula:
T
DTS=(L-H)/C
Air+ (H/Cmat)
Wherein Cmat is the ultrasonic velocity of substrate.
Peak value 72,74 because passing air, sound differs widely, so will distinguish in time well with the speed of passing the wall material.In order to explain the data of these tracks, two door 76a, 76b can be set, to select DTA signal 72 or DTS signal 74.In the honeycomb substrate inspection method, DTS signal 74 can be used to construct the raster-scanned image of expression uncontinuity.When measure net on the turning axle of said structure 25 circumferential crack or during other uncontinuity, the DTS image can produce about inherent vice or heteropical better expression.
Figure 10 A and 10B show in proving installation to be had (Figure 10 B) and not to have signal amplitude and the gained track of time under the situation of honeycomb filter of (Figure 10 B) jam-pack.Figure 10 A shows (not having substrate in the proving installation) signal amplitude and the gained track of time in open air, and demonstrates DTA peak value 78, and this peak value has reacted the scope (Fig. 8) of the distance L between above-mentioned two transducers 33,35.In the track of Figure 10 B, demonstrate DTS peak value 79. Peak value 80 and 81 is the repeatedly reflections from this filter end, and can be ignored effectively.DTS peak value 79 has the amplitude that can change in each position according to whether uncontinuity or heterogeneity are arranged in the filtrator.For non-contacting method and apparatus, employed system must be the ultrasonic test system of noncontact, for example, and can be from the model SIA7 of VN Instruments company purchase and the model iPASS of Ultran company.Also can use the discrete component transducer to or array.Under non-contacting situation, can use wider frequency range.For example, the driving frequency of transducer can be between 150KHz and 1.5MHz, between 200KHz to then better between the 700KHz.
After finishing raster scanning, can produce two images.Image is the image of the variation of the comprehensive response (IR) of the DTS signal in this substrate of expression or signal intensity.Another image is the image of variation that is used for representing the TOF of this substrate DTS signal.In raster-scanned image, will be formed for representing inner uncontinuity or inner heteropical pattern.Figure 11 shows the raster scanning IR image of DTS intensity, and it demonstrates the axial crack that has bifurcated in having the cordierite honeycomb formula substrate of 600/4 physical dimension.Figure 12 shows raster scanning TOF image, and it also demonstrates the axial crack that has same bifurcated.
Under the too weak situation of DTS signal, can select DTA signal 72 with door 76, and can use above-mentioned identical process.Influenced by cell density from the DTA of same substrate and the relative intensity of DTS signal, promptly 900/2 of substrate and 400/6 or 600/4, influenced by the frequency of operation of ultrasonic transducer.In other words, the airborne sound wave relevant with cell-wall thickness with unit size can influence wave propagation, i.e. DTS74 or DTA72.Therefore, based in the listed frequency range of this paper, carrying out best result of experiment, need to regulate best test frequency.
Because promptly there is significant acoustic impedance mismatch in the restriction that the non-contact ultrasonic test is intrinsic, so the DTS signal is generally all quite faint between air and the solid.In order to provide enough signal to noise ratio (S/N ratio)s to the DTS signal, each scanning position place preferably has a plurality of signal averagings.The raster-scanned image of gained is that IR or TOF image will more easily disclose trickle feature (crackle and/or heterogeneity).Whether there is a feature (crackle and/or heterogeneity) that is disclosed by using pulse echo methods defined herein or transmission method, can verifying.Correspondingly, can use the combination of method described herein.
Although described the present invention in conjunction with better embodiment, various modifications and interpolation should be tangible for a person skilled in the art.All these interpolations, variation and modification all are included in the scope of the present invention, and this scope is limited by claims and equivalence thereof.
Claims (21)
1. a method that is used for detecting the internal feature of fired or green ceramics cellular structure comprises the steps:
(a) ultrasonic transmitter is placed near first external position on the cellular structure;
(b) ultrasonic receiver is placed near second external position on the cellular structure;
(c) drive transmitter to produce ultrasound wave, the inside of cellular structure is passed in described ultrasound wave conduction;
(d) receive modulated ultrasound wave at the receiver place;
(e) produce a response signal based on modulated ultrasound wave;
(f) from described response signal, filter out noise so that produce filtered response signal; And
(g) analyze filtered response signal and do not have inner uncontinuity or heterogeneity to define.
2. detection method as claimed in claim 1 is characterized in that,
The ultrasonic transmitter at described primary importance place and the receiver at second place place are oriented to contact with cellular structure engagement.
3. detection method as claimed in claim 2 is characterized in that,
The ultrasonic transmitter at described primary importance place is oriented to contact engagement with the opposite end face of cellular structure with the receiver at second place place.
4. detection method as claimed in claim 3 is characterized in that,
The ultrasonic transmitter at described primary importance place is oriented to contact engagement with the same end face of cellular structure with the receiver at second place place.
5. detection method as claimed in claim 3 is characterized in that,
The described primary importance and the second place are same positions, and transmitter and receiver comprise ultrasonic transceiver.
6. detection method as claimed in claim 1 is characterized in that,
The ultrasonic transmitter at described primary importance place and the receiver at second place place are positioned at same position place and cellular structure engagement basically, and
Wherein when at the part place of cellular structure internal reflection taking place, ultrasound wave produces modulated ultrasound wave.
7. detection method as claimed in claim 1 is characterized in that,
Drive described transmitter to produce ultrasound wave less than about 5MHz.
8. detection method as claimed in claim 7 is characterized in that,
Drive described transmitter to produce the ultrasound wave between about 150-700kHz.
9. detection method as claimed in claim 8 is characterized in that,
Described cellular structure comprises the passage and the gas permeable wall of jam-pack, and drives described transmitter to produce the ultrasound wave between about 150-500kHz.
10. detection method as claimed in claim 8 is characterized in that,
Described cellular structure comprises flow-through substrate, and drives described transmitter to produce the ultrasound wave between about 500-700kHz.
11. detection method as claimed in claim 1 also comprises the steps:
Transmitter and receiver are repositioned onto the place of test position again that opens with first and second location intervals with respect to cellular structure, and repeating step (c)-(g).
12. detection method as claimed in claim 1 is characterized in that,
Described cellular structure is the particle filter that comprises the jam-pack passage.
13. detection method as claimed in claim 1 is characterized in that,
Described cellular structure is the material that is selected from trichroite, silit, mullite and aluminium titanates, perhaps then just forms the material that is selected from trichroite, silit, mullite and aluminium titanates if described cellular structure is a green ceramic bodies when being fired.
14. detection method as claimed in claim 1 is characterized in that,
The material that is used to form cellular structure has the total porosity rate between about 15%～85% when being fired.
15. detection method as claimed in claim 1 is characterized in that,
Described transmitter contacts engagement with receiver by the relative position place that separates that relative relation is positioned at cellular structure.
16. detection method as claimed in claim 1 is characterized in that,
Described transmitter and receiver are positioned on the cellular structure toward each other, and comprise the steps: to make transmitter to be repositioned onto the position of opening by relative relation, and repeating step (c)-(g) with first and second location intervals with receiver.
17. detection method as claimed in claim 1 is characterized in that,
Described transmitter is included in the transmitter array, and described receiver is included in the receiver array.
18. detection method as claimed in claim 1 is characterized in that,
Described transmitter and receiver are positioned near the position relative on the cellular structure by relative relation and do not contact with it.
19. detection method as claimed in claim 18 also comprises the steps:
Transmitter and receiver are relatively moved with respect to cellular structure, and repeating step (c)-(g).
20. detection method as claimed in claim 1 is characterized in that,
Described ceramic honeycomb structure has air flue and substrate passageways, and described ultrasonic transmitter and receiver be positioned on the air flue in the described structure, and described structure is a green ceramic bodies.
21. detection method as claimed in claim 1 is characterized in that,
Described ceramic honeycomb structure has air flue and substrate passageways, and described ultrasonic transmitter and receiver be positioned on the air flue in the described structure, and described structure is fired pottery.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/US2006/019098 WO2007133215A1 (en) | 2006-05-16 | 2006-05-16 | Ultrasonic testing method and device for ceramic honeycomb structures |
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| CN101438150B CN101438150B (en) | 2012-06-27 |
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| WO (1) | WO2007133215A1 (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102680578A (en) * | 2011-02-08 | 2012-09-19 | 波音公司 | Structural health monitoring system |
| CN103119434A (en) * | 2010-11-25 | 2013-05-22 | Imal有限责任公司 | An apparatus for detecting inhomogeneities |
| CN104990982A (en) * | 2015-07-31 | 2015-10-21 | 中航复合材料有限责任公司 | Automatic scanning-based cellular core sandwich structure ultrasonic imaging detection method |
| CN108844978A (en) * | 2018-05-29 | 2018-11-20 | 沈阳飞机工业（集团）有限公司 | It is a kind of for detecting the new method of honeycomb interior defect |
| CN112129833A (en) * | 2016-01-05 | 2020-12-25 | 雅马哈精密科技株式会社 | Ultrasonic inspection method |
| CN113302488A (en) * | 2018-11-15 | 2021-08-24 | 康宁股份有限公司 | Ultrasonic inspection for ceramic structures |
| CN116761665A (en) * | 2020-12-18 | 2023-09-15 | 雷尼恩斯有限公司 | Method and system for reducing negative ion pollution and emission |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54139784A (en) * | 1978-04-21 | 1979-10-30 | Ngk Insulators Ltd | Method and device for testing ceramic piece having innumerable through pores |
| US4869944A (en) * | 1987-02-12 | 1989-09-26 | Ngk Insulators, Ltd. | Cordierite honeycomb-structural body and a method for producing the same |
-
2006
- 2006-05-16 WO PCT/US2006/019098 patent/WO2007133215A1/en active Application Filing
- 2006-05-16 CN CN2006800545990A patent/CN101438150B/en active Active
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103119434A (en) * | 2010-11-25 | 2013-05-22 | Imal有限责任公司 | An apparatus for detecting inhomogeneities |
| CN103119434B (en) * | 2010-11-25 | 2015-06-17 | Imal有限责任公司 | An apparatus for detecting inhomogeneities |
| US9719967B2 (en) | 2011-02-08 | 2017-08-01 | The Boeing Company | Structural health monitoring system |
| CN102680578A (en) * | 2011-02-08 | 2012-09-19 | 波音公司 | Structural health monitoring system |
| CN104990982B (en) * | 2015-07-31 | 2020-09-22 | 中航复合材料有限责任公司 | Honeycomb sandwich structure ultrasonic imaging detection method based on automatic scanning |
| CN104990982A (en) * | 2015-07-31 | 2015-10-21 | 中航复合材料有限责任公司 | Automatic scanning-based cellular core sandwich structure ultrasonic imaging detection method |
| CN112129833A (en) * | 2016-01-05 | 2020-12-25 | 雅马哈精密科技株式会社 | Ultrasonic inspection method |
| CN112129833B (en) * | 2016-01-05 | 2024-09-24 | 雅马哈精密科技株式会社 | Ultrasonic inspection method |
| CN108844978A (en) * | 2018-05-29 | 2018-11-20 | 沈阳飞机工业（集团）有限公司 | It is a kind of for detecting the new method of honeycomb interior defect |
| CN108844978B (en) * | 2018-05-29 | 2020-11-13 | 沈阳飞机工业（集团）有限公司 | Novel method for detecting internal defects of honeycomb |
| CN113302488A (en) * | 2018-11-15 | 2021-08-24 | 康宁股份有限公司 | Ultrasonic inspection for ceramic structures |
| CN116761665A (en) * | 2020-12-18 | 2023-09-15 | 雷尼恩斯有限公司 | Method and system for reducing negative ion pollution and emission |
| CN116761665B (en) * | 2020-12-18 | 2024-04-16 | 雷尼恩斯有限公司 | Method and system for reducing negative ion pollution and emission |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2007133215A1 (en) | 2007-11-22 |
| CN101438150B (en) | 2012-06-27 |
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