Indeed, shearography can be employed in fieldfactory settings. Holography suffers from several inherent technical problems such as the requirements. International symposium on structural health monitoring and nondestructive testing 45 oct 2018, saarbrucken germany shm ndt 2018 session. During the certification exam of level 2 shearography testing, the questionnaires relating to the specific part relate more particularly to procedures used in the aircraft industry. Shearography as nondestructive testing method in the application of adhesive tapes. In addition, ndt can also identify situations that could potentially lead to critical failures. This paper presents an optical technique referred to as shearography for nondestructive inspection. The images are obtained through a digital camera or a closed couple device viewing the. Pdf shearography as nondestructive testing method in the.
This affordable system provides wholefield, noncontact, nondestructive testing for rapid widefield inspection of composites. Shearography has been proved highly effective for nondestructive testing. A shearography camera produces a realtime picture of the test part, showing tiny, submicroscopic dimples and bulges on the surface of a test part when a. Nondestructive testing ndt is critical to many precision industries because it can. Xray cabinets ndt engineering tecnitest ingenieros. Defect dtect is a small, modular and versatile shearography system comprising an illumination module, an imaging module and a control unit. The highly sensitive interferometric sensor can measure and detect microscopic surface outofplan deformations caused by. This affordable system provides wholefield, noncontact, nondestructive testing for rapid widefield inspection of composites, bonded structures and other advanced materials. Michael schuth university of applied sciences trier fh. Robotic q800 shearography ndt dantec dynamics delivered in 2008 a fully automatic. Electronic shearography or digital speckle shearing interferometry dssi has found applications as an ndt tool in industrial environments due to its less stringent vibration isolation requirement and simple optical setup.
The shearography tire test system intact 16002 is designed for the serial testing of retreaded or new passenger car, light truck, em and aircraft tires, as well as for the control of tire carcasses before retreading. The experimental setup ofdigital shearography is shown below on the right side. Shearography is an areal working, optical measurement procedure. Intact shearography tire testing ndt and inspection. Because of its numerous advantages, shearography is.
Shearography is a new ndt technology that has evolved from work in the 1960s and 70s in the area of laser holography. The flawscout is an inspection solution for nondestructive testing ndt and quality control applications, commonly used on composites and metallic materials. Acoustic shearographyusing sound to excite the test partis the first nasa certified ndt method for the inspection of space shuttle foam to prevent a reoccurrence of the columbia accident. Interferometric ndt methods have a long history in the laboratories of daimler benz aerospace airbus, even first papers about early approaches to shearography go back into the late seventies, when in the lemwerder labs of former vfwfokker the first shearography setup was assembled 1. Applied sciences free fulltext digital shearography for ndt. Many lti systems also include automatic image stitching to create an image file of the entire part for rapid comparison to cad or catia files. As a new feature, the mobile isismobile shearography system now introduces a fully integrated robot interface for an automatic test procedure. Phase stepping shearography for testing commercial aircraft. Application of laser shearography ndt in various industries 4 figure 1. Computational and experimental approach for nondestructive. Thermography is a surface thermal radiation measuring technique. It uses coherent light or coherent soundwaves 1 to provide information about the quality of different materials in nondestructive testing, strain measurement, and vibration analysis. Comparison of digital shearography with cscan ultrasonic technique for the nondestructive testing of a graphite sandwich panel with foam core measuring. Shearography is an interferometric technique for fullfield and noncontacting measurement of surface deformation displacement or displacement derivatives.
Our lti5100hd features megapixel plus resolution, continuous realtime phase map imaging and many unique and advanced features designed for the ultimate performance in shearography ndt. Shearography ndt systems use a common path interferometer to image the first derivative of the outofplane deformation of the test part surface in response to a change in load. Using ut to characterize defects in composites detected with. Laser ndt laser nondestructive testing nondestructive. Shearography nondestructive testing has evolved considerably since first used. The system has three degrees of freedom and an additional turntable. The system is based on laser shearography and consists of a sensor unit and a laptop with controlling and reporting software. Combination of the typical toptobottom shearography ndt strategy with. Key words suggested by authors shearography, inspection, flaw detection, nde. Shearography nondestructive testing is providing a better and faster means.
Let users know what you would have wanted to know about this company. That book has greatly contributed to enabling better understanding and improvement of the digital shearography technique. Michael schuth university of applied sciences trier fhtrier 4. Introduction originally developed as a strain measurement technique y y hung 1974 shearography is a laser based interferometric technique that is sensitive to the outofplane deformation of a surface. Sensitive to submicroscopic deformations in the surface of a test object, shearography produces a video image of surface strain within a sensitivity typically on the order of 0. Digital shearography and applications trends in optical nondestructive testing and inspection, pp287308. Nondestructive testing ndt based on laser technology has witnessed incremental acceptance in the ndt industry since the early 1990s with shearography and holography interferometry as the most widely recognized techniques based on this technology. It is suitable especially for the characterization of composite materials such as fiber reinforced plastics frp and. The shearography camera uses laser light to detect weak areas of the structure.
It has been more than a decade since spie press published the first book on shearography in 2003. Typical ndt workflow by laser shearography 6 figure 1. Flawscout ndt dantec dynamics precision measurement. Using ut to characterize defects in composites detected. Shearography is an interferometric technique developed to address several limitations of holography. Ndt expert the ultimate control xxxxxx titre xxxx ndt expert the basic principles of the measurement method are interferometry and correlation techniques interferometry is determination of fractional relative phase difference between light waves traversing different paths. Shearography or speckle pattern shearing interferometry is a measuring and testing method similar to holographic interferometry. Intro to shearography free download as powerpoint presentation. Field ndt inspections with shearography digital shearography ndt system q810 applications infield use for large area ndt inspections detection of delaminations, disbonds, kissing bonds, wrinkling impact damage, crushed core and much more defect detection in composite materials carbon fiber, glass fiber, laminates, honeycomb etc. One major difference of shearography from other ndt techniques is the mechanics of revealing flaws. The object under inspection is illuminated with a single mode laser.
The method is used for defect detection in an expedited manner. Thermography and shearography article spatial phase shift shearography for enhanced ndt christopher petry 2, prof. It will be shown that b y coupling the methods, the detection is more reliable and the defect evaluation more. Portable shearography ndt systems portable shearography systems generally are either tripod mounted or attached in some manner to the test object fig. Also the laboratory has capability to conduct ndttesting of spot weld for determination of nugget size. The x axis moves the turntable inwards and outwards. Shearography a practical optical testing and measuring. It is suitable especially for the characterization of composite materials such as fiber reinforced plastics frp and sandwich materials with honeycomb or foam cores.
Aug 16, 20 nondestructive testing ndt based on laser technology has witnessed incremental acceptance in the ndt industry since the early 1990s with shearography and holography interferometry as the most widely recognized techniques based on this technology. Nondestructive testing and evaluation using phaseshifting. Robot shearography ndt manual ndt inspections are no better than the daily shape of the operator todays aerospace composite subassemblies becoming more complex, the ndt systems used need to be more sophisticated. The applicability for operational use is limited by its major disadvantage, the sensitivity for disturbances. Laser shearography is a rapid yet sensitive, noncontact method of ndt that can quickly inspect a structure to determine the extent of subsurface anomalies such as disbonds and voids. Aerospace ndt is the first industry handbook published by asnt. It is the technique using laser speckle as the carrier ofthe displacement information, recording the. Ndt, especially for ndt of composite materials used in the automotive, aerospace. Laser shearography is an opticalbased nondestructive testing ndt technique that can identify internal material discontinuities or anomalies in homogenous and nonhomogenous materials in an accelerated manner. Shearography is extensively used in production and development in aerospace, wind rotor. It uses coherent light or coherent soundwaves to provide information about the quality of different materials in nondestructive testing, strain measurement, and vibration analysis. Jun 04, 2009 acoustic shearography using sound to excite the test partis the first nasa certified ndt method for the inspection of space shuttle foam to prevent a reoccurrence of the columbia accident. Shearography technique to identify defects in almost any material slightest surface excitation leads to surface deformations from the internal flaws the shearography system can detect these very small deformations fullfield, noncontact technique.
The new system configuration effectively and precisely satisfies. Aug 25, 2010 shearography technology and applications. This is the simple htmltext version of the pdf file 4114kb. Shearography a practical optical testing and measuring method. Over the past decade, integration of lasers with ultrasonic testing has seen commercial acceptance in a number of different applications. Phenomena which can be measured are those which influence the phase of the.
New innovations make shearography and tvholography more useful in ndt applications many different types of defects can be detected the methods have several modes of operation for both static and dynamic excitation new shearography technology gives increased potential for testing of. Shearography is an optimal ndt solution, tailored specifically for integrated quality control processes used in the qualification of material structural integrity. This important distinction is responsible to two key phenomena. Shearography is an interferometric method which allows fullfield observation of surface displacement derivatives. The study explores the strength s and weaknesses of both non destructive testing ndt methods. This research paper presents the study of thermography and shearography to evaluate cfrp reinforcement of concrete structures. Shearography is an interference optical technique which measures surface deformation and reveals flaws by looking for flawinduced deformation anomalies. In this paper, a phase shifting electronic shearography technique and its application in nondestructive testing ndt is described. It reveals flaws in materials by looking for flawinduced strain anomalies. Nondestructive testing ndt by laser shearography and.
Unlike holography, shearography does not require a reference beam and hence it is more tolerable to environmental disturbances. Inspection throughputs for our automated shearography systems are as high as 1,000 sq. It is predestined for the ndt of composite materials as it works materialindependently. Nde of aerospace cfrp composites with laser shearography. This interface consistently continues our philosophy of incorporating base technologies into a userfriendly environment, thus allowing users to benefit from maximum system integration. Active thermal shearography and infrared thermography. Aerospace ndt, shearography ndt, honeycomb structure, ndt, disbond, damage, delamination 1. Phase stepping shearography for testing commercial.
Digital shearography nondestructive testing laboratory. One major difference of shearography from other ndt techniques is the. Download ultrasonics pdf files on marine safety, cargo bulletins, hatch cover testing, maintenance, ultrasonic testing, iacs rec 14 and 15. Nondestructive testing ndt methods, or nondestructive inspection ndi methods, are applied to determine the physical condition of an object, performed in a way, so that it is not altering or permanently changing the properties of the object 2. Shearography is a highresolution optical ndt method for identification and characterization of structural defects in components and has gained wide acceptance over the last decade. Nondestructive testing using shearography springerlink. The thermal excitation system for shearography tess provides radiant heating with continuous digital measurement of the surface temperature profile to ensure repeatability. Theory and application of digital speckle pattern shearing interferometry by wolfgang steinchen and lianxiang yang. Typical laboratory shearography setup typical laboratory shearographic ndt systems, similar to the one depicted in fig. A nondestructive testing method for a large variety of different composite materials. All non destructive testing agent concerned by a level 2 certification. Isis shearography ndt ndt and inspection product and.
Nondestructive testing ndt is critical to many precision industries because it can provide important information about the structural health of critical components and systems. The light, which reflects off the object surface, is viewed through a set of shearing optics. Portable system use laser diodes and various means such as vacuum changes, thermal flux or vibration to stress the object surface to detect subsurface anomalies. Laser shearography ndt flawexplorer ndt the flawexplorer is a portable, compact, and robust laser shearography inspection system for nondestructive testing ndt and quality control applications for composites and metallic materials with inspection areas from 10 cm 2 up to 2 m 2 20 ft 2 in one shot. This also forces the ndt inspection methods to become contactless to be able to achieve a high inspection quality and. Digital shearographic nondestructive testing laboratory. Intact 12201 intact 12002 passenger car light trick tires the system variant intact 12001 offers a wide field of applications especially for the use at retreaders operating with smaller numbers of tires, in test laboratories and for tire development purposes. Nondestructive testinginspection of composite materials. Shearography reveals defects in an object by identifying defectinduced deformation anomalies which are more relevant to structural weakness. Digital shearography, also called tv shearography, is a further technical development of shearography. The tess device functions as an accessory to any electronic shearography device. Digital shearography the manner in which shearography measures the rate at which an object deforms under stress is is as follows. Phase measurement technique and recent developments article pdf available in applied sciences 812.
That time using film or thermoplast camera the method proved to be too complicated for in field applications. Shearography is a remote nondestructive testing method which is capable of monitoring the mechanical behavior of objects under load. New innovations make shearography and tvholography more useful in ndt applications many different types of defects can be detected the methods have several modes of operation for both static and dynamic excitation new shearography technology gives increased potential for testing of large structures. Laser shearography ndt laser shearography is an optical measurement technique for nondestructive testing ndt and quality control applications, commonly used on composites and metallic materials.
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