A system for evaluating a bond includes first and second electrodes. A dielectric material layer is positioned at least partially between the first and second electrodes. A power source is connected to the first and second electrodes. The power source is configured to cause the first and second electrodes to generate an electrical arc. The electrical arc is configured to at least partially ablate a sacrificial material layer to generate a plasma.

A method for examining a sample (50) including the steps of exciting a propagating mechanical deformation (2) in the sample (50) using a fluidic oscillator (10), and determining a characteristic of the mechanical deformation (2).

A thermoacoustic transducer integrating at least one piezoelectric element having a first surface and a second surface, a potential electrode that is electrically connected to the second surface, a ground electrode that is electrically connected to the first surface, a switch electrically connected to both the potential electrode and the ground electrode, a timer configured to match a pulse emanating from a radio-frequency emitter, further wherein the potential electrode and the ground electrode are electrically connected through an impedance when the switch is in an active state, further wherein the potential electrode and the ground electrode are not electrically connected when the switch is in an inactive state; and a housing accommodating the at least one piezoelectric element, potential electrode, ground electrode, and switch.

A testing system for causing a physical change in a crack tip region of a crack within a specimen. The testing system includes a load application system for applying a load to the specimen having the crack formed therein, an electrothermal system for applying an electrical current through the specimen and comprising a power supply and a controller operably coupled to the load application system and the electrothermal system. The load application system configured to perform a crack growth test on the specimen. A method of thermally influencing a crack tip region of a crack within a specimen includes applying at least one pulse of current to the specimen to generate flux tangentially around the crack within the specimen and at the crack tip region and causing the crack tip region of the crack within the specimen to reach a predetermined activation temperature.

A tapered fiber optoacoustic emitter includes a nanosecond laser configured to emit laser pulses and an optic fiber. The optic fiber includes a tip configured to guide the laser pulses. The tip has a coating including a diffusion layer and a thermal expansion layer, wherein the diffusion layer includes epoxy and zinc oxide nanoparticles configured to diffuse the light while restricting localized heating. The thermal expansion layer includes carbon nanotubes (CNTs) and Polydimethylsiloxane (PDMS) configured to convert the laser pulses to generate ultrasound. The frequency of the ultrasound is tuned with a thickness of the diffusion layer and a CNT concentration of the expansion layer.

A thermoacoustic measurement probe may include an open-ended hollow radio-frequency (RF) waveguide; and a thermoacoustic transducer, wherein the open-ended hollow RF waveguide, in the form of a sleeve, surrounds and is mechanically joined to the thermoacoustic transducer.

A device for particle sensing is disclosed. The device includes a sensor including a bulk acoustic wave resonator having a resonant frequency, an acoustic mirror arranged to support the resonator, and a heater in thermal communication with the resonator such that a resonator temperature is based on a heater temperature. The device also includes circuitry connected to the sensor. The circuitry comprises a driver configured to drive the heater with a driver signal having a constant periodic cycle, and an oscillator configured to generate an output signal indicative of the resonant frequency. The resonant frequency is modulated by the resonator temperature.

A thermoacoustic probe for a thermoacoustic imaging system, the probe including: a radio-frequency (RF) applicator having an insert, wherein the applicator is configured to transmit at least one radio frequency source; an integral electromagnetic matching and acoustic extinction layer having a substantially flat-planar side and a substantially convex side, wherein the substantially flat-planar side of the integral electromagnetic matching and acoustic extinction layer is coupled to the insert of the RF applicator; and an optical transducer coupled to the substantially convex side of the integral electromagnetic matching and acoustic extinction layer.

A processing system according to an embodiment includes a processing device. The processing device receives a detection result of a reflected wave from a detector that includes multiple detection elements arranged in a first direction and a second direction crossing each other, and performs a probe that includes transmitting an ultrasonic wave toward a welding object and detecting the reflected wave. The processing device performs a first determination of determining a joint and a non-joint at multiple points along the first and second directions of the welding object based on the detection result. The processing device performs a second determination of determining an appropriateness of a result of the first determination based on the detection result or the result of the first determination.

A tapered fiber optoacoustic emitter includes a nanosecond laser configured to emit laser pulses and an optic fiber. The optic fiber includes a tip configured to guide the laser pulses. The tip has a coating including a diffusion layer and a thermal expansion layer, wherein the diffusion layer includes epoxy and zinc oxide nanoparticles configured to diffuse the light while restricting localized heating. The thermal expansion layer includes carbon nanotubes (CNTs) and Polydimethylsiloxane (PDMS) configured to convert the laser pulses to generate ultrasound. The frequency of the ultrasound is tuned with a thickness of the diffusion layer and a CNT concentration of the expansion layer.