In this paper, a new non-contact ultrasonic abrasive finishing mechanism is designed and fabricated. This mechanism combines the function of ultrasonic vibrations and the magnetic abrasive finishing (MAF) process. A permanent magnet which is mounted on a horn has been used as the processing tool. This polishing tool is vibrated at an ultrasonic frequency with piezo-electric actuators. Ultrasoni...

A combination of laser-induced ultrasound generation and ultrasonic holography for spatial control of the generated ultrasonic pulse is presented. Ultrasound is produced by absorption of laser pulses at an absorbing layer in a water tank via the optoacoustic effect. In order to produce a defined ultrasonic frequency in the MHz range, the laser pulses are harmonically time-modulated using an aco...

Ultrasonic measurement techniques can be used to determine some characteristics of turbulent flows. In this work measurements of the difference in propagation times of ultrasonic waves along two paths are combined with the Kolmogorov (j )-power law to study characteristics of grid-generated turbulence. The paper focuses on ultrasonic measurements of turbulent flow using the travel-time techniqu...

introduction: periodontitis is an inflammatory periodontal disease that leads to tooth loss. recently laser has been introduced as an alternative treatment for periodontitis. the aim of the present study was to compare the effect of erbium-doped yttrium aluminum garnet (er:yag) laser with ultrasonic scaler in patients with moderate chronic periodontitis. methods: in this randomized single-blind...

Pulse ultrasound technique has been applied to measure the reflected echo signals from vapor bubbles in boiling two-phase flow. In this study, an ultrasonic transducer was developed for the ultrasonic measurement in boiling two-phase flow under the atmospheric pressure. Since the Curie point of piezoelements of the transducer is above 250 ̊C, it has an allowable temperature limit of 120 ̊C. The b...

In this work, machining test was carried out in various machining conditions using ultrasonic vibration capable CNC machine. For work material, alumina ceramic (Al2O3) was used while for tool material diamond electroplated grinding wheel was used. To evaluate ultrasonic vibration effect, grinding test was performed with and without ultrasonic vibration in same machining condition. In ultrasonic...

A new type of highly-directional ultrasonic range sensor is designed, fabricated, and tested in this paper. To improve directivity, the parametric acoustic array, a nonlinear effect of media between two intensive waves, is applied to an ultrasonic range sensor. Additionally, a new type of the stepped-plate transducer is applied for generating high amplitude waves consisting of two frequencies. ...

In this study, spherical Nb2O5 nanoparticles were synthesized by a novel chemical method as a simple, robust, surfactant-free, non-toxic and widely applicable approach. In order to investigate the effect of initial concentration on particle sizes, nanoparticles with different initial concentration were synthesized. Ultrasonic assisted method was applied and the effects of ultrasonic treat...

Ultrasonic characterization of microstructure evolution during processing" (2007). Many cold-working processes for polycrystalline metals cause alignment of the grains with a single symmetry axis. This type of microstructure is called fiber texture. The existence of a preferred orientation of the grains has a significant influence on the propagation and scattering of ultrasonic waves, which are...

The well-known thermo-elastic effect of laser irradiation can be exploited to produce strong localized stresses when an expanded, long pulse, low-intensity laser beam is used to irradiate the specimen. These stresses will produce a parametric modulation of the received ultrasonic signals, that is somewhat similar to the acousto-elastic effect often used in nonlinear ultrasonic studies. It is sh...