In a measuring arrangement for determining properties of a material to be extruded while an extrusion process is being carried out in an extruder, at least one extruder screw is rotatably mounted in a tubular guide in a barrel and is connected to a rotary drive. Material to be extruded is fed to the tubular guide at one end and is removed as finish-extruded material at an oppositely arranged discharge. Arranged at measuring positions at predeterminable defined intervals on the wall of the tubular guide along the longitudinal axis of the extruder screw are multiple first sound transducers, which are designed for the detection of sound waves that are generated during the extrusion process by the extrusion process as process noises and/or are emitted by a second sound transducer, arranged at one end of the tubular guide, in the direction of the longitudinal axis of the extruder screw and into the material to be extruded that is conveyed through a mixing chamber present in the tubular guide.

Non-destructive inspection systems (10) and methods for inspecting structural flaws that may be in a structure (15) based on guided wave thermography. The method may include sweeping a frequency-phase space to maximize ultrasonic energy distribution across the structure while minimizing input energy, e.g., via a plurality of actuators. The system may include transducer elements (12, 14, 16, 17) configured to predominantly generate shear horizontal-type guided waves in the structure to maximize thermal response from any flaws.

A lithium tantalate single crystal substrate for a surface acoustic wave device that is a rotated Y-cut LiTaO3 substrate whose crystal orientation has a Y-cut angle of not smaller than 36° and not larger than 49° and which has such a Li concentration profile after diffusion of Li into the substrate from the surface thereof that the Li concentration at the surface of the substrate differs from that inside the substrate. A shear vertical type elastic wave whose main components are vibrations in the thickness direction and in the propagation direction and which is among those elastic waves which propagate in the X axis direction within the surface of this LiTaO3 substrate has an acoustic velocity of not lower than 3140 m/s and not higher than 3200 m/s.

A system for monitoring the condition of elongate structural elements, for example, railway rails, and a method of designing and manufacturing the system is disclosed. The method includes identifying and selecting suitable modes of propagation and signal frequencies that can be expected to travel large distances through an elongate structural element; designing a transducer that will excite the selected mode at the selected frequency; numerically modelling the transducer as attached to the elongate structural element; validating the transducer design by analysing a harmonic response of the selected mode of propagation to excitation by the transducer, and manufacturing one or more transducers for use in the system.

System include an ultrasonic transducer configured to couple to a nondestructive testing (NDT) sample and configured to produce and direct an ultrasonic probe wave at a selected frequency into a subsurface region of the NDT sample, a 3D laser scanning vibrometer configured to direct a detection beam in a scan area on a surface of the NDT sample and to receive a return beam from the scan area, and to detect, based on the return beam, a 3D motion of the surface across a wideband frequency range, and a processor, and a memory configured with instructions that, when executed by the processor, cause the processor to produce sub-surface image data of the NDT sample at multiple harmonics of the selected frequency in the wideband frequency range based on the detected 3D surface motion, wherein the sub-surface image data describes a nonlinear defect response produced in the NDT sample by interaction of the ultrasonic probe wave with the subsurface region.

Disclosed are a linkage device, a transceiver module and a plane stress field measuring device and method capable of achieving synchronous adjustment of distance and angle, and relates to the field of ultrasonic non-destructive testing. The existing technical means for measuring plane stress in the field of ultrasonic testing has the shortcomings that the same testing is only applicable for single materials and the deflection angles of transmitting and receiving transducers are inconsistent. In the application, the linkage device designed by comprising a distance adjusting screw, an angle adjusting screw, a left connecting rod, a right connecting rod, a shaft column and a column lock is adopted, and based on the linkage device, the transceiver module designed by comprising a receiving end wedge, a receiving probe, a transmitting end wedge and a transmitting probe is additionally arranged; based on the transceiver module, the measuring device designed by comprising a pulse transmitting device, an amplifying device and a data acquisition device is additionally arranged, and the stress measuring method applicable for the stress measuring device is provided; and the distance and deflection angle between the receiving probe and the transmitting probe of the detection are adjusted according to a tested part. The application applies to stress measurement in the manufacturing process of mechanical components.

A light-acoustic system and method for detecting an anomaly in a structure are provided. The system includes a light source configured to emit an excitation light and at least one excitation element attached to a surface of a structure. The at least one excitation element includes a photostrictive material and is configured to receive the excitation light for generating an oscillating strain. The oscillating strain generates an acoustic wave in the structure. The system also includes a detector configured to detect the acoustic wave.

Methods and devices are provided for analyzing a tubular structure including at least two electromagnetic-acoustic transducers (EMAT) and, called sensors, attachable or attached in, on or in the vicinity of the tubular structure; and computation and/or memory resources, that are accessed locally and/or remotely and that are configured to determine, for the pair of sensors, a function representing the impulse response of the tubular structure on the basis of the diffuse acousto-elastic noise present in the structure. Developments describe the use of rings supporting the sensors; translation and/or rotation movements; permanent or temporary installations; hinged rings; various computation modes, e.g., intercorrelation, a passive inverse filter, or correlation of the coda of the correlation; the use of artificial noise sources, imaging (e.g., tomography) for determining the existence of one or more defects in the structure. Software aspects are described.

The present disclosure provides methods and systems for the characterization of a potential microtexture region (MTR) of a sample, component, or the like. The methods may include determining a threshold width of spatial correlation coefficient and/or a threshold spatial correlation coefficient slope for an actual MTR, characterizing a potential MTR as an actual MTR or a defect, characterizing an actual MTR as an acceptable MTR or not, and/or characterizing various components with potential MTRs as defective or not. The characterization may include calculating a width of spatial correlation coefficient and/or a spatial correlation coefficient slope of the potential MTR and comparing the width of spatial correlation coefficient to a threshold width of spatial correlation coefficient and/or comparing the spatial correlation coefficient slope to a threshold spatial correlation coefficient slope for the potential MTR to be characterized as an actual MTR or a defect (crack).

An ultrasonic dry coupled wheel probe with radial transducers emit ultrasound in substantially all radial directions relative to a longitudinal axis. The probe does not require normalization and is efficient in directing ultrasound to a surface being inspected. The probe has a wheel composed of rubber or other materials for acoustically dry coupling the transducer to the surface. A first transducer is composed of a piezoelectric material so that the transducer receives an electrical signal, vibrates, and generates and transmits sound, such as ultrasound. Similarly, a second transducer receives sound such as ultrasound, vibrates, and generates a corresponding electrical signal. The transducer arrangement both transmits ultrasound to the surface and receives the reflection of the ultrasound from the surface. An acoustic barrier separates the transmitting component from the receiving component. The transducer has annular electroplates adjacent to the piezoelectric material. The two transducers can comprise a single, integrated transducer module.