An ultrasonic probe (2) comprises a cMUT chip (20), which has a plurality of vibration elements whose electromechanical coupling coefficient or the sensitivity changes depending on a bias voltage, and transmits/receives an ultrasonic wave; an acoustic lens (26) provided on the ultrasonic wave radiation side of the cMUT chip (20); a backing layer (22) provided on the back side of the cMUT chip (20) for absorbing propagation of the ultrasonic wave; an electric wiring portion (flexible substrate (72)), which is provided from the peripheral portion of the cMUT chip (20) to the side face of the backing layer (22) and has a signal pattern connected with the electrode of the cMUT chip (20) arranged thereon; and a housing (ultrasonic probe cover (25)) for containing the cMUT chip (20), the acoustic lens (26), the backing layer (22) and the electric wiring portion (flexible substrate (72)). A ground layer (conductive film (76)) of ground potential is provided on the ultrasonic wave radiation side of the cMUT chip (20).

Ultrasonic probe and method for manufacturing the same and ultrasonic diagnostic device

One of the problems preventing the industrial application of ceramic-matrix composites is the lack of an efficient method to detect and discriminate among types of damage occurring during service. With this in mind, the mechanical response, damage development and acoustic emission activity during monotonic tensile testing of a BMAS glass-ceramic matrix reinforced with SiC fibres have been investigated. Damage initiation and propagation were easily detected and evaluated using the acoustic emission technique. Comparing the acoustic emission activity characteristics in simple lay-ups with those of more complex lay-ups allowed discrimination between matrix microcracking, matrix macrocracking accompanied by interface debonding, and delamination cracking. In this way, the paper contributes to the development of the acoustic emission technique for in situ monitoring of damage development in ceramic-matrix composites.

Acoustic emission during tensile testing of SiC-fibre-reinforced BMAS glass-ceramic composites

A torque-angle wrench is provided with a handle for applying torque, such as to a fastener or bolt, through a tightening angle, at a rotational angular velocity. A piezoelectric gyroscopic sensor device including circuitry for vibrating an oscillating body is coupled to the wrench. As the wrench is rotated through the tightening angle, its rotational angular velocity causes the vibrating body to alter its direction of vibration. The new vibrating pattern is sensed and converted, by appropriate sensing circuitry, into an electrical signal proportional in intensity to the rotational angular velocity of the wrench. The electrical signal can be electronically processed by appropriate conversion and display circuitry to provide a visual indication of the tightening angle. Such conversion and display circuitry can be integral with the wrench or as part of an adaptably coupled meter non-integrally connected to the sensor device.

Torque angle wrench

A method and apparatus for ultrasonic in-process monitoring and feedback of resistance spot weld quality uses at least one transducer located in the electrode assembly transmitting through a weld tip into an underway weld Analysis of the spectrum of ultrasonic waves provides the operator with an indication of the size, thickness, location, dynamics of formation and quality of the spot weld The method presents a fundamentally new physical approach to the characterization of the spot weld quality Together with transmission mode it includes new modes of operation of ultrasonic probes such as a reflection mode and simultaneous use of transmission and reflection modes, and a new physical interpretation of the signal analysis results

Ultrasonic in-process monitoring and feedback of resistance spot weld quality

We detected and mapped the subsurface extent of the Hertzian crack on the surface of a silicon nitride ball using optical coherence tomography. We find that the crack propagates initially perpendicular to the surface for about 50 μm after which it bends at an angle of ∼20 degrees to the surface. These measurements are compared with predictions of crack propagation theories based on principal stresses and on maximum strain energy release.

Subsurface detection and characterization of Hertzian cracks in Si3N4 balls using optical coherence tomography

The present invention relates to an acoustic microscope system having an ultrasonic probe that is driven with a high-frequency burst signal to radiate an ultrasonic signal and that detects the resulting reflected and irradiated waves, a Z-axis moving device that updates the vertical distance Z between the probe and a material of interest for each sampling position, and device for constructing a V(z) curve from the reflection signals obtained at respective sampling positions. The ultrasonic probe of the invention is provided with an acoustic lens, a first ultrasonic transducer for receiving a leaky surface skimming compressional wave reflected from a sample material on one side of the acoustic lens, and a second ultrasonic transducer also provided on the side of the acoustic lens for receiving a leaky surface acoustic wave.

Acoustic microscope system

An advanced high frequency ultrasonic imaging system has been developed for detecting fine flaws in ceramics. This system consists of a computer for data and image processing, a high precision xyz-scanner with an immersion transducer, a high frequency (5–150 MHz) pulser, a receiver, and a peak detector. By using the imaging system with high frequency from 50 to 100 MHz, a 10-μm tungsten wire embedded 1·5 mm under the surface in SiC ceramic is detected. Some image processing techniques are used to enhance the ultrasonic image and detect fine flaws with low reflection echo levels.

Ultrasonic testing for flaw detection in ceramics

PURPOSE:To implement the method by which the axial force of the bolt is accurately controlled and manufacturing man-hours of the bolt is reduced, by detecting the position where the energy of the ultrasonic wave which is transmitted from the surface of the object to be tightened is changed by a specified amount. CONSTITUTION:An ultrasonic wave probe 11 is arranged in the vicinity of the bolt on the surface 12 of the objects 3 which are tightened by the bolt 1 and a nut 2. The ultrasonic wave is transmitted in the direction toward a contact interface 8 forming a boundary part of the objects to be tightened from the surface 12. In this case, when the ultrasonic probe 11 is arranged at a point A on the top surface 12 of the object to be tightened 3, the transmitted ultrasonic wave passes through the contact interface 8, reflected by a lower surface 13, and returned. When the ultrasonic wave probe 11 is arranged on a point B, the ultrasonic wave is reflected by the contact interface 8 under the open state, and returned. Based on the correlation of the positions at which the reflected echo changes and the axial force Ff of the bolt 1, the axial force Ff which is generated in said bolt 1 is detected, and its adequacy for practical use is controlled.

Method for controlling axial force of bolt utilizing ultrasonic wave

Controller for axial force of bolt

In an ultrasonic inspection method and apparatus for inspecting the presence or absence of a defect in an object to be inspected by receiving as an RF signal a reflection beam of an ultrasonic beam emitted from a probe to the object and displaying data of the RF signal on a display unit, a maximum value indicative of a positive peak of the RF signal is detected, a maximum absolute value indicative of a negative peak of the RF signal is detected, a computation is performed for comparing in magnitude the maximum value indicative of the positive peak with the maximum absolute value indicative of the negative peak, and a computed value is displayed on the display unit so that the presence or absence of a phase inversion of the RF signal may be judged for deciding the presence or absence of a defect in the object.

Takeda Sakae

Papers

Acoustic microscope system

Ultrasonic testing for flaw detection in ceramics

Method for controlling axial force of bolt utilizing ultrasonic wave

Controller for axial force of bolt

Ultrasonic inspection apparatus