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1
Content available The Effect of Power Ultrasound on Microstructure Evolution During the Transient Liquid Stage of Ultrasonic-Promoted TLP Bonding SiCp/Al MMCs
Zhou Changzhuang, Ma Lin, Zhu Chao, Cui Qinghe, Liang Jindi, Song Yujian
Archives of Metallurgy and Materials
|
2022
|
Vol. 67, iss. 4
1283--1291
EN
Ultrasound-promoted transient liquid phase bonding (U-TLP) is a high quality, high efficiency, and low-cost method for fast bonding of difficult-wetting materials in the atmospheric environment. In this paper, U-TLP was used to bond SiC particles reinforced aluminium-based metal matrix composite which particle volume fraction was 70%. The pure zinc foil was used as the intermediate layer. The effects of ultrasonic on microstructure evolution and mechanical properties of joints during the transient liquefaction stage were investigated. The mechanism of ultrasonic effects in the transient liquefaction stage of U-TLP was also inducted. The results showed that high volume fraction SiCp/Al MMCs were bonded well at low temperature in the air environment. Ultrasonic vibration can remove the oxide film on the surface of aluminum matrix composites, enhance the wettability of SiC particles with weld metal, promote atomic diffusion and homogenization of SiC particles, and improve the welding quality and efficiency. Reasonable increase of ultrasonic vibration time could effectively improve the joint strength.
2
Content available Application of acoustic emission to the analysis of phase transformations in 27MnCrB5-2 steel tests during continuous cooling
Trafarski Andrzej, Łazarska Małgorzata, Ranachowski Zbigniew
Bulletin of the Polish Academy of Sciences. Technical Sciences
|
2021
|
Vol. 69, nr 6
art. no. e139389
EN
The goal of the research was to analyze the acoustic emission signal recorded during heat treatment. On a special stand, samples prepared from 27MnCrB5-2 steel were tested. The steel samples were heated to 950°C and then cooled continuously in the air. Signals from phase changes occurring during cooling were recorded using the system for registering acoustic emission. As a result of the changes, Widmanstätten ferrite and bainite structures were observed under a scanning microscope. The recorded acoustic emission signal was analyzed and assigned to the appropriate phase transformation with the use of artificial neural networks.
3
Content available A Comparison of Composite Specimens Damage area Measurements Performed using Pulsed Thermography and Ultrasonic NDT Methods
Luziński Rafał, Ziemkiewicz Jarosław, Synaszko Piotr, Żyluk Andrzej, Dragan Krzysztof
Fatigue of Aircraft Structures
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2019
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Iss. 11
68--77
EN
Carbon fiber reinforced plastics (CFRPs) are widely used in aerospace structures due to their high stiffness, strength and good fatigue properties. They are however vulnerable to loads perpendicular to their plane and, while impacted, can suffer significant internal damage decreasing their overall strength. Detecting and sizing such damage is an important task of the non-destructive inspection (NDI) methods. This study was conducted to detect and quantify damage in a set of six impacted even rectangular CFRP specimens designed from a MiG-29 vertical stabilizer’s skin. The inspection was done using the ultrasonic (UT) method (based on mobile scanner – MAUS V) and the pulsed infrared thermographic (IRT) method. Each specimen’s inside and outside (impacted) surface was inspected separately with IRT, while the outside surface was then inspected with UT. UT provided the most precise measurements of the damage area, while the IRT inspection of the outside surface (which would be accessible on a real aircraft structure) provided underestimated values due to the damage’s depth and geometry.
4
Content available Removal of Cr(VI) using a novel adsorbent modification. Ultrasonic method with apricot kernel shells
Kalipci E., Namal O. O.
Environment Protection Engineering
|
2018
|
Vol. 44, nr 3
79--93
EN
Raw apricot kernel shells (AKS) and ultrasound-modified apricot kernel shells were used as adsorbents for the removal of Cr(VI) from aqueous solutions. For raw and modified AKS, the experimental data well fitted to the Langmuir isotherm and adsorption kinetics was suited to pseudo-second order kinetic model indicating chemisorption as the rate-limiting step. For raw and modified AKS, maximum adsorption capacities obtained from the Langmuir adsorption model were 6.5 mg/g and 9.9 mg/g, respectively. Maximum Cr(VI) adsorption was obtained at a pH 2 and optimum stirring speed was determined as 250 rpm. After ultrasound modification, an increase for Cr(VI) adsorption was observed. Raw AKS as low-cost natural biomaterial can be preferred for the removal of Cr(VI) when compared to other adsorbents. Ultrasonic modification can be used to improve the efficiency of Cr(VI) removal.
5
Nowoczesne metody sterowania generatorami ultradźwiękowymi
Kardyś W., Milewski A., Kogut P., Kluk P.
Elektronika : konstrukcje, technologie, zastosowania
|
2016
|
Vol. 57, nr 6
47--50
PL
W artykule przedstawiono dostępne metody sterowania falownikiem rezonansowym w generatorach ultradźwiękowych. Skupiono się na najnowszych metodach sterowania o wysokiej rozdzielczości regulacji. Zaprezentowano metodę wytwarzania sygnałów sterujących falownikiem rezonansowym z wykorzystaniem mikrokontrolera STM32F334 oraz wyniki badań porównawczych różnych rozwiązań układów generacji przebiegów sterujących.
EN
The article presents available methods of resonant converter control in ultrasonic generators. New methods of control with high resolution of frequency regulation have been presented. Method of generation of resonant converter control signals with STM32F334 microcontroller have been shown as well as measurement results of various generation circuits.
6
Innowacyjne technologie ultradźwiękowe opracowane w Instytucie Tele- i Radiotechnicznym
Krzemiński Ł., Nafalski L., Młynarski B., Kogut P., Król K., Kiełbasiński Marcin, Kluk P., Kardyś W., Niemiec M., Gostkowski H.
Elektronika : konstrukcje, technologie, zastosowania
|
2016
|
Vol. 57, nr 6
12--16
PL
W artykule przedstawiono szeroki wachlarz zastosowań ultradźwięków oraz postęp w dziedzinie ich zastosowania w różnych technologiach na przykładach opracowywanych w ITR w okresie ostatnich dziesięciu lat (tj. 2006–2016).
EN
The article presents a wide range of applications of ultrasound and progress in the field of their application in various technologies in the examples developed in the ITR for the past ten years (ie . 2006–2016).
7
Content available Identification of meat types by ultrasonic methods
Nowak K. W.
Technical Sciences / University of Warmia and Mazury in Olsztyn
|
2015
|
nr 18(2)
79--84
EN
The ability of identification of meat types using ultrasonic measurement was evaluated in this work. Four types of muscles were analyzed (turkey breast and thigh, and pork loin and ham). Ultrasonic measurements were performed at storage (5 ±1oC) and room (20±1oC) temperatures using the through-transmission technique and differential method of determination of sound velocity and the attenuation coefficient. The mean values of sound velocity for the breast, thigh, loin and ham were respectively: 1550.7, 1536.6, 1558.7, 1559.7 m/s at the storage temperature, and 1582.7, 1578.5, 1596.9, 1592.7 m/s at the room temperature. The mean values of the attenuation coefficient in the same order were: 21.3, 23.2, 30.6, 28.1 m-1 and 22.2, 18.9, 22.0, 22.4 m-1. Statistically significant differences in the sound velocity were observed between pork and turkey muscles, therefore, the meat of those species can be identified based on ultrasound measurements of sound velocity. The attenuation coefficient cannot be applied in the identification of meat types due to absence of significant differences in the mean values.
8
Technologia jednoczesnego zgrzewania i cięcia włóknin wielowarstwowych w sposób ciągły na przykładzie urządzenia AZW-10
Brylski M., Gawryś P., Krzemiński Ł., Młynarski B.
Elektronika : konstrukcje, technologie, zastosowania
|
2012
|
Vol. 53, nr 8
46-49
PL
W artykule przedstawiono badania technologiczne nad procesem jednoczesnego zgrzewania i cięcia wielowarstwowych włóknin w sposób ciągły. Opisano zastosowany zestaw ultradźwiękowy oraz dwa stanowiska badawcze. Na koniec opisano komercyjne urządzenie AZW-10, którego konstrukcja uwzględnia wnioski wynikłe z opisanych badań i jest efektem prowadzonych prac.
EN
The paper presents the technological research on the process of simultaneous welding and cutting of multilayer woven in fabric a continuous manner an ultrasonic set and two research stands are described. The AZW-10 commercial machine is described in which the results of the research work are implemented.
9
Sonotroda do maceracji materiałów roślinnych
Gawryś P., Kogut P., Krzemiński Ł., Młynarski B.
Elektronika : konstrukcje, technologie, zastosowania
|
2012
|
Vol. 53, nr 8
52-55
PL
W artykule przedstawiony został reaktor z sonotrodą jednostopniową półfalową oraz proces modelowania sonotrody trzystopniowej metodą elementów skończonych, która została wykonana i przebadana w zestawie z przetwornikiem ultradźwiękowym 20 kHz 4 kW. Wyniki badań zostały porównane z parametrami modelu. Następnie omówiono fizyczne zjawiska wpływające na zużycie sonotrody w środowisku pracy i sposób szacowania trwałości reaktora.
EN
The paper presents a reactor with half-wave single-stage sonotrode, with a process of modeling of a three-stage sonotrode by finite element method, which was then physically implemented and tested with 20 kHz 4 kW ultrasonic transducer. The results were compared with those resulting from the model. Then, the physical phenomena influencing the use of the sonotrode in the work environment and way of estimating the durability of a reactor are discussed.
10
Content available Metodyka badania wybranych skał Polski w warunkach wysokiego ciśnienia i temperatury
Dziedzic A., Łukaszewski P.
Biuletyn Państwowego Instytutu Geologicznego
|
2011
|
nr 446 (1)
123--128
PL
W artykule przedstawiono opis metodyki badań wytrzymałościowych skał w warunkach wysokiego ciśnienia i temperatury. Badania wytrzymałościowe prowadzono w warunkach konwencjonalnego trójosiowego ściskania z równoczesną rejestracją zmian prędkości fali ultradźwiękowej. Zestaw badawczy wykorzystywany w Zakładzie Geomechaniki UW, składający się ze sztywnej prasy wytrzymałościowej wyposażonej w komorę termociśnieniową oraz z ultradźwiękowego systemu pomiarowego, umożliwia automatyczną, zsynchronizowaną rejestrację zmian naprężenia, odkształcenia oraz prędkości fali podłużnej w próbkach skalnych poddanych ściskaniu w komorze termociśnieniowej. Dzięki zastosowaniu opisanej metodyki możliwe jest porównanie uzyskanych danych z wynikami geofizycznych badań in situ.
EN
The study presents methodology for rock testing in conventional triaxial conditions with simultaneous recording of longitudinal wave speed velocity. Assembled at Department of Geomechanics of Warsaw University, the testing unit consists of a rigid strength press equipped with thermal pressure vessel and ultrasonic measuring system. Testing set is able to records automatically the changes of stress, strain and longitudinal wave velocity during strength test conducted in the thermal pressure vessel. Described methodology allows comparing obtained data with in situ geophysical investigations.
11
Content available remote The influence of ultrasonic disintegration aided with chemicals on the efficiency of sewage sludge centrifugation
Bień J., Kowalczyk M., Kamizela T., Mrowiec M.
Environment Protection Engineering
|
2010
|
Vol. 36, nr 1
35-43
EN
The dewatering efficiency of sewage sludge during its centrifugation was assessed using two methods: sludge was either conditioned by chemicals (cement, ash, gypsum) or exposed to the ultrasonic field and conditioned by these chemicals. The overall goal of this research was to prove that the ultrasonic field energy and the chemical substances can change the structure of sewage sludge by increasing the size and the packing ability of particles, and at the same time the quantity of gravitational water present in sewage sludge. This improves the efficiency of sewage sludge dewatering. The efficiency of mechanical dewatering can be increased by combining the method of initial sonication with adding chemicals during sewage sludge conditioning. We observed an increase in the velocity of flocculation which was related to the dispersing effect of ultrasounds. The addition of chemically neutral substances led to more efficient thickening of sewage sludge conglomerates. During mechanical dewatering these conglomerates maintained more rigid structure with reduced compressibility which resulted in their elevated porosity at high pressures and improved the dewatering ability of sludge. This decreased final hydration and changed the distribution coefficient in reference to the parameters of unconditioned sewage sludge during dewatering.
12
Content available remote The fate of heavy metals during thermal and ultrasound treatment of activated sludge
Laurent J., Pierra M., Casellas M., Dagot C.
Environment Protection Engineering
|
2009
|
Vol. 35, nr 3
5-15
EN
The fate of cadmium and copper during thermal and ultrasound treatments of activated sludge was studied in terms of mixed liquor physicochemical modifications. Biochemical composition of sludge testfied to the solubilization of its biopolymers. Granulometric measurements demonstrated that ultrasound and temperature induced respectively floc disintegration and macrofloc deflocculation. The uptake of the two metals by sludge flocs was improved with an increase in temperature. Both metals were in a different way adsorbed by sludge flocs, since mass transfer improvement together with the extended surface area offered by sonicated flocs increased the cadmium adsorption. At the same time, an increase in soluble organic ligands limited copper uptake.
13
Content available remote Phenomenological model of changes in the speed of a sound wave in crystals caused by dopants
Błachowicz T.
Archives of Acoustics
|
2004
|
Vol. 29, no. 3
447-459
EN
The paper examines theoretically changes in the speed of an acoustic wave in crystals caused by metallic dopants. It is well known that an acoustic wave has a wavelength larger than the typical dimension of the elementary crystallographic cell, so it is sensitive only to large-scale features. The model bases on the assumption that a crystal with uniform distributed dopants can be transformed into a multiplayer virtual structure form which some conclusions can be drawn. The approach presented is valid for longitudinal acoustic waves, where the atomic displacement can be considered as a continuum field. It provides positive or negative changes in the acoustic wave speeds for different dopants in a hypothetical lithium niobate crystal.
14
Oczyszczanie ultradźwiękowe w roztworach wodnych a ciśnienie promieniowania ultradźwięków
Niemczewski B.
Elektronika : konstrukcje, technologie, zastosowania
|
2000
|
Vol. 41, nr 12
45-47
PL
Badano ruchy wody, mierzone parciem na stożek pomiarowy radiometru, pod wpływem ciśnienia promieniowania ultradźwięków, w funkcji temperatury, przy czterech częstotliwościach ultradźwięków: 27 , 33, 37 i 60 kHz. Przy trzech z wymienionych częstotliwości, zgodnie z oczekiwaniami, ruchy te były niewielkie w stosunku do występujących w stosowanych do oczyszczania ultradźwiękowego rozpuszczalnikach organicznych. Natomiast przy częstotliwości 33 kHz, w temperaturach około 40-55°C, stwierdzono bardzo intensywne ciśnienie promieniowania.
EN
There have been made investigations of movements of water measured by pressure exerted on a measuring cone of an acousticc radiometer, induced by ultrasounds pressure versus temperature at four frequencies: 27, 33, 37 kHz. At three of the above frequencies, as expected, the movements were minor as compared to those in organic cleaning solvents whereas at 33 kHz and at about 40-55°C the pressure of ultrasounds was found to be very intense.
15
Supression of chaotic oscillations of gas bubbles by polymer additives
Brujan E. A.
Applied Mechanics and Engineering
|
2000
|
Vol. 5, no 2
485-498
EN
The effect of polymer concentration on the bifurcation structure of a bubble oscillator is theoretically examined in terms of bifurcation diagrams and phase diagrams. The equation describing the driven spherical oscillations of a gas bubble in CMC aqueous solutions is obtained by using a Williamson model fluid. The numerical results reveal the suppression of chaotic oscillations of bubbles by polymer additives.
16
Content available remote In vitro measurements of ultrasonic parameters in saturated and dry bone tissues as a function of frequency
Pakuła M., Kaczmarek M., Kubik J.
Acta of Bioengineering and Biomechanics
|
1999
|
Vol. 1, nr 2
49-53
EN
The purpose of the paper is to describe the application of the method of ultrasonic spectroscopy to study wave propagation parameters: wave velocity and attenuation in saturated and dry trabecular bovine bones. The discussion concerns dilatational waves within the frequency range were visible influence of dissipation of mechanical energy, internal structure and scattering effects of the materials on wave parameters takes place.
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