A multi-material inspection system and velocity measurement method of critically refracted longitudinal wave based on single-angle wedges belong to the field of nondestructive testing of high-end equipment. The method includes the following steps: designing a transmitting wedge and a receiving wedge with the same inclination angle, and building phased array ultrasonic-based inspection systems of critically refracted longitudinal wave; estimating a longitudinal wave velocity range of a material to be tested, calculating and optimizing a phased array ultrasonic delay law, and building a relation between a longitudinal wave velocity and an amplitude of critically refracted longitudinal wave; reading and interpolating the arrival time of a received signal, and calculating a longitudinal wave velocity of the material to be tested; determining an optimal delay law, and exciting and receiving a critically refracted longitudinal wave.

An acoustic technique can be used for performing non-destructive testing. For example, a method for acoustic evaluation of a target can include generating respective acoustic transmission events via selected transmitting ones of a plurality of electroacoustic transducers, and in response to the respective acoustic transmission events, receiving respective acoustic echo signals using other receiving ones of the plurality of electroacoustic transducers, and coherently summing representations of the respective received acoustic echo signals to generate a pixel or voxel value corresponding to a specified spatial location of the target. Such summation can include weighting contributions from the respective representations to suppress contributions from acoustic propagation paths outside a specified angular range with respect to a surface on or within the target, such as to provide an acoustic path-filtered total focusing method (PF-TFM).

The use of nondestructive inspection (NDI) capabilities for the detection of fatigue cracks extending from fastener holes in multi-layered metallic structures without removing the fastener; including at least the use of a probe guide containing a UT sensor and either an inertial measurement unit (IMU) or a rotary encoder, and either of these options could be applied in testing of either raised head fasteners or flush fasteners.

An ultrasonic testing device performs flaw detection on a stringer having an inner circumferential surface of a substantially rectangular shape closed in a transverse section. The ultrasonic testing device includes: a shoe configured to be in contact with a corner of the inner circumferential surface of the stringer; an ultrasonic array configured to be fixed to the shoe to define, together with the shoe and the corner a medium space in which a contact medium used for propagating an ultrasonic wave is enclosed, and configured to transmit an ultrasonic wave to the corner and receive a reflected ultrasonic wave; and a forcing unit configured to be in contact with a corner and push the shoe against the corner.

A system for inspecting a structure includes a laser ultrasound device configured to direct laser light onto a surface of the structure that generates ultrasonic waves within the structure and to generate an array of ultrasound data representative of the ultrasonic waves. The system includes a robotic arm configured to move the laser light across the surface. The system includes a multiplex controller configured to trigger generation of the ultrasonic waves within the structure at an inspection location and to receive the array of ultrasound data for the inspection location. The system includes a computer system that includes a motion-control module configured to control movement of the laser light relative to the surface of the structure, a motion-tracking module configured determine when the laser light is at the inspection location, and an inspection module configured to process the array of ultrasound data to inspect the structure at the inspection location.

A device, for non-destructive testing of a mechanical part made of a polycrystalline material, includes: an ultrasonic probe including a two-dimensional array of transducers capable of emitting and receiving signals at different excitation angles; and a processing module suitable for controlling the emission and the reception of the transducers, for processing the signals received by the transducers so as to express the signals received by the ultrasonic probe in two planar wave planes constructed from the emission and reception wave vectors of the probe, and for deducing therefrom information representative of the three-dimensional orientation of the fiber structure of the mechanical part.

A system for measuring a number of layers in a layered environment includes an ultrasound transducer positioned at an exterior surface of a first layer at a first location. At least one receiving sensor is positioned perpendicular to the exterior surface of the first layer at a second location. The ultrasound transducer and the at least one receiving sensor are in communication with a computer processor, power source, and computer-readable memory. The ultrasound transducer is configured to emit a first ultrasound signal into the first layer at the first location. The at least one receiving sensor is configured to receive a plurality of propagated ultrasound signals. The processor is configured to determine a total number of layers in the layered environment based on at least one from the set of: a number of signals received and a number of propagation direction changes only of the first ultrasound signal.

A method of performing an automated non-destructive examination of a composite structure includes identifying surface damage on the composite structure, coupling an automated tap tester device to a surface of the composite structure at a location of the surface damage, and performing, with the automated tap tester device, a plurality of tapping impacts on the surface within a testing area that encapsulates the surface damage. The method also includes receiving a plurality of acoustic signals associated with the plurality of tapping impacts, modeling sub-surface damage associated with the surface damage based on an analysis of the plurality of acoustic signals.

A system for determining a trigger amplitude indicating a precursor to a material fracture in a specimen under test includes a microphone converting acoustic emission emitted by the specimen under test into electrical signals. A load is exerted upon the specimen under test and the acoustic emission are emitted when the load causes the specimen under test to undergo deformation prior to the material fracture. A control module is in electrical communication with the microphone and executes instructions to monitor the electrical signals generated by the microphone and filter the electrical signals generated by the microphone. The control module converts the electrical signals generated by the microphone into individual frequency components based on a fast Fourier Transform (FFT). The individual frequency components each include a peak intensity. The control module determines the trigger amplitude based on the peak intensity of the individual frequency components of the FFT.

Disclosed is a method of determining a characteristic of a measurement intermediate layer (220) in a multilayer structure (200) using an ultrasonic transducer (100), wherein the multilayer structure (200) includes a first layer (210), a measurement intermediate layer (220) and a third layer (230) in series abutment. The method comprises transmitting a measurement ultrasonic signal into the first layer (210) towards the measurement intermediate layer (22)0, measuring a measurement reflection of the measurement ultrasonic signal from the multilayer structure (200), determining, using the measurement reflection, a measured frequency response of the measurement intermediate layer (220), determining a plurality of modelled frequency responses of the measurement intermediate layer (220), comparing the measured frequency response to the plurality of modelled frequency responses, and determining the characteristic of the measurement intermediate layer (220) based on the comparison of the measured frequency response and the plurality of modelled frequency responses.