This work was supported by the National Natural Science Foundation of China (Grant No. 11374245), the NIH under Grant No. P41-EB2182, the Natural Science Foundation of Fujian Province, China (Grant No. 2013J01163), and the Open Research Fund of the State Key Laboratory of Acoustics, Chinese Academy of Science (Grant No. SKLA201306).

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	<li>Jaffe, B., Cook, W. R., Jaffe, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Piezoelectric Ceramics. , (1971).</li><li>Chaussy, C., Thuroff, S., Rebillard, X., Gelet, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Technology+insight:+High-intensity+focused+ultrasound+for+urologic+cancers.">Technology insight: High-intensity focused ultrasound for urologic cancers.</a> Nat. Clin. Pract. Urol. 2, 191-198 (2005).</li><li>Haar, G. T., Coussios, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+intensity+focused+ultrasound:+physical+principles+and+devices.">High intensity focused ultrasound: physical principles and devices.</a> Int. J. Hyperthermia. 23, 89-104 (2007).</li><li>Topolov, V. 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Phys. 92, 2451 (2002).</li><li>Pujol, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+solution+of+nonlinear+inverse+problems+and+the+Levenberg-Manquardt+method.">The solution of nonlinear inverse problems and the Levenberg-Manquardt method.</a> Geophysics. 72, 1-16 (2007).</li><li>Mor&#233;, J. J., Garbow, B. S., Hillstrom, K. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=User+Guide+for+MINPACK-1.">User Guide for MINPACK-1.</a> Argonne National Laboratories Report ANL-80-74. , (1980).</li><li>Tang, L. G., Cao, W. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temperature+dependence+of+self-consistent+full+matrix+material+constants+of+lead+zirconate+titanate+ceramics.">Temperature dependence of self-consistent full matrix material constants of lead zirconate titanate ceramics.</a> Appl. Phys. Lett. 106, 052902 (2015).</li><li>Topolov, V. Y., Bowen, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inconsistencies+of+the+complete+sets+of+electromechanical+constants+of+relaxor-ferroelectric+single+crystals.">Inconsistencies of the complete sets of electromechanical constants of relaxor-ferroelectric single crystals.</a> J. Appl. Phys. 109, 094107 (2011).</li><li>Berlincourt, D., Krueger, H. H. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Properties of Morgan Electroceramic ceramics. Technique publication TP-226. , (2000).</li><li>Migliori, A., Sarrao, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Resonant ultrasound spectroscopy. , (1997).</li><li>Zadler, B. J., Le Rousseau, J. H. L., Scales, J. A., Smith, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resonant+ultrasound+spectroscopy:+Theory+and+application.">Resonant ultrasound spectroscopy: Theory and application.</a> Geophys. J. Int. 156, 154-169 (2004).</li></ol>

Authors have nothing to disclose.

ここで説明RUS技術は、自己整合性を保証することができるように、サンプルからサンプルへの特性変化に起因する誤差を排除するだけのサンプルを使用して完全なセットの材料定数を測定することができます。それらは、圧電又はない場合の方法は、高い品質係数Qを有する任意の固体材料に関係なく使用することができます。他のすべての標準的な特徴付け技術は、フルセットのデータを取...

チタン酸ジルコン酸鉛（PZT）の圧電セラミックス、（1-x）は3 -xPbTiO 3によるPbZrO、およびその誘導体が広く1950 1は、超音波トランスデューサ、センサおよびアクチュエータに使用されてきました。これらの電気機械デバイスの多くは、宇宙船および地下井戸ロギングなどの高い温度範囲にて使用されます。また、このような治療超音波トランスデューサ、圧電トランスやソナープロジェクター、運転中にしばしばヒートアップなどの高電力デバイス、。このような温度上昇は、深刻なパフォーマンスの低下を引き起こし、共振周波数およびトランスデューサの焦点を変更します。高い強度は、既に腫瘍の治療のための臨床診療で使用される超音波（HIFU）技術は、PZTセラミックス製の超音波トランスデューサを使用して焦点を当てました。動作中は、これらの変換器の温度が順番にHIを変更しますPZT共振器の材料定数の変化を引き起こし、増加しますFU焦点だけでなく、出力電力2,3。焦点のシフトではなく、癌組織の破壊される深刻な不要な結果、 すなわち 、健康な組織につながる可能性があります。焦点ずれを予測することができる一方、一つは、このようなずれを補正するために電子設計を使用することができます。したがって、圧電材料の完全なセットの材料特性の温度依存性を測定する多くの電気機械デバイス、特にハイパワーデバイスの設計及び評価のために非常に重要です。 分極した強誘電体材料は、今日知られている最高の圧電材料です。実際には、現在使用されているほぼ全ての圧電材料が固溶体PZTセラミックスと（1-x）でのPb（Mgの1/3のNb 2/3）O 3 -xPbTiO 3（PMN-PT）単結晶を含む強誘電体材料が、あります。インピーダンス共鳴法IEEE（電気電子学会）がdrastiで5-7のサンプルを必要としますフルセットの材料定数4を特徴付けるために的に異なる形状。分極の程度は試料の幾何学的形状（境界条件）に依存するため、試料の特性は分極のレベルに依存しつつ、強誘電性材料のためのIEEEインピーダンス共鳴法を用いて、自己矛盾のないフルセットのマトリクスデータを取得することはほぼ不可能です。変化をサンプリングするサンプルによって引き起こされる問題を回避するために、すべての定数は、一つのサンプルから測定されるべきです。 Li らは、パルスエコー超音波と逆インピーダンス分光5の組み合わせを用いて、室温で1サンプルからすべての定数の成功した測定を報告しました。残念ながら、この技術は、炉内に直接超音波測定を行うことができないため、高温で行うことは困難です。高温で動作することができない市販のせん断トランスデューサもありません。トランス結合した他に、カップリンググリースデューサとサンプルは高温で動作することはできません。 原理的には、RUSの技術は、一つのサンプル6,7を用いた圧電材料とその温度依存性の完全なセットの材料定数を決定する能力を有します。しかし、RUS法の適切な実施のためのいくつかの重要なステップがあります。まず、室温でテンソル特性のフルセットは、正確にパルスエコーとRUS技術の組み合わせを使用して決定されるべきです。第二に、この室温のデータセットは、共振周波数を予測するために、対応するモードを識別するために測定されたものと一致するために使用することができます。第三には、室温までの温度の各小増分のために、1は、測定された共鳴スペクトルから、この新たな温度でフルセットの定数を取得するために測定された共鳴スペクトルに対するスペクトル再構成を実行する必要があります。そして、新たな出発点として、新しいデータセットを使用して、我々はできます<html>次の温度でフルセットの定数を取得するために別の小さな温度ステップによって温度を上昇させます。このプロセスを続けると、私たちはフルセットの材料定数の温度依存性を得ることができるようになります。 ここでは、PZT-4圧電セラミックサンプルはRUS法の測定手順を説明するために使用されます。 5弾性定数、3圧電定数と2誘電率：分極反転PZT-4セラミックは10の独立した材料定数と∞m対称性を有します。誘電定数は、共振周波数の変化に鈍感であるので、それらは別々に、同じサンプルを用いて測定しました。クランプ誘電率の温度依存性<img alt="式3" src="/files/ftp_upload/53461/image003.jpg" />そして<img alt="式4" src="/files/ftp_upload/53461/image004.jpg" />無料の誘電定数ながら、容量測定から直接測定しました。OAD / 53461 / image005.jpg &quot;/&gt;と<img alt="式（2）" src="/files/ftp_upload/53461/image002.jpg" />同時に測定データの整合性チェックとして使用しました。一定の電界での弾性スティフネス定数の温度依存性<img alt="式6" src="/files/ftp_upload/53461/image006.jpg" /> 、 <img alt="式（7）" src="/files/ftp_upload/53461/image007.jpg" /> 、 <img alt="式8" src="/files/ftp_upload/53461/image008.jpg" /> 、 <img alt="式9" src="/files/ftp_upload/53461/image009.jpg" />そして<img alt="式10" src="/files/ftp_upload/53461/image010.jpg" /> 、圧電応力定数が15、E 31、E及びE 33は、同じ試料を用いRUS法によって決定しました。

<table><tbody><tr><td>PZT-4</td><td>TRS</td><td></td><td></td></tr><tr><td>paraffin</td><td>MTI Corporation</td><td>8002-74-2</td><td></td></tr><tr><td>conductive silver paint</td><td>MG Chemicals</td><td>842-20G</td><td></td></tr><tr><td>Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; Powder</td><td>MTI Corporation</td><td></td><td></td></tr><tr><td>coupling grease</td><td>Panametrics</td><td></td><td></td></tr></tbody></table>

characterization of full set material constants and their temperature dependence for piezoelectric materials using resonant ultrasound spectroscopy

高電力電気機械デバイスの動作中に、温度上昇は、デバイス性能の低下を引き起こす原因で機械的および電気的損失を避けられません。コンピュータシミュレーションを用いて、このような劣化を評価するために、高温で完全なマトリックス材料特性は、入力として必要とされています。異なる形状のサンプル間の強い異方性の性質及び特性の変化に起因する強誘電体材料のようなデータを測定することは極めて困難です。脱分極の程度に依存境界条件であるため、大幅に異なる形状を有する複数のサンプルを必要とするIEEE（電気電子学会）インピーダンス共鳴技術によって得られたデータは、通常、自己一貫性を欠いています。共鳴超音波分光法（RUS）技術がvariatをサンプリングするサンプルによる誤差をなくすことができる唯一の​​一つのサンプルを用いて測定されるようにフルセットの材料定数を可能にしますイオン。詳細RUS手順は、チタン酸ジルコン酸鉛（PZT-4）圧電セラミックのサンプルを使用してここで実証されます。実施例では、材料定数の完全なセットは、120℃の室温から測定しました。測定された無料の誘電率<img alt="式（1）" src="/files/ftp_upload/53461/image001.jpg" />そして<img alt="式（2）" src="/files/ftp_upload/53461/image002.jpg" />測定されたフルセットのデータに基づいて算出したものと比較して、圧電定数は15 DおよびD 33は 、異なる式を用いて計算しました。優れた契約はRUSによって得られたデータセットの自己整合性を確認し、温度の全範囲で発見されました。

反転に使用されるLMアルゴリズムは、極小のファインダーです。したがって、弾性スティフネス定数の初期値<img alt="式6" src="/files/ftp_upload/53461/image006.jpg" /> 、 <img alt="式（7）" src="/files/ftp_upload/53461/image007.jpg" /> 、 <img alt="式8" src="/files/ftp_upload/53461/image008.jpg" /> 、 <img alt="式9" src="/files/ftp_upload/53461/image009.jpg" /> 、および<img alt="式10" src="/files/ftp_upload/53461/image010.jpg" />圧電?...

Watch this Scientific Journal Video about Characterization of Full Set Material Constants and Their Temperature Dependence for Piezoelectric Materials Using Resonant Ultrasound Spectroscopy at JoVE.co

Characterization of Full Set Material Constants and Their Temperature Dependence for Piezoelectric Materials Using Resonant Ultrasound Spectroscopy

This protocol describes the procedure of measuring the temperature dependence of the full set material constants of piezoelectric materials using resonant ultrasound spectroscopy (RUS).

フルセット材料定数のキャラクタリゼーションと共鳴超音波スペクトロスコピーを用いた圧電材料のための彼らの温度依存性

During the operation of high power electromechanical devices, a temperature rise is unavoidable due to mechanical and electrical losses, causing the ...

characterization-full-set-material-constants-their-temperature

Universidad de Cartagena UDEC

Research

JoVE Journal

Engineering

9.4K ビュー.  Xiamen University. This protocol describes the procedure of measuring the temperature dependence of the full set material constants of piezoelectric materials using resonant ultrasound spectroscopy (RUS). 

ビデオ: Characterization of Full Set Material Constants and Their Temperature Dependence for Piezoelectric Materials Using Resonant Ultrasound Spectroscopy

Characterization of Thermal Transport in One-dimensional Solid Materials

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials, including conductive, semi-conductive or nonconductive one-dimensional structures. This technique broadens the measurement scope of materials (conductive and nonconductive) and improves the accuracy and stability. If the sample (especially biomaterials, such as human head hair, spider silk, and silkworm silk) is not conductive, it will be coated with a gold layer to make it electronically conductive. The effect of parasitic conduction and radiative losses on the thermal diffusivity can be subtracted during data processing. Then the real thermal conductivity can be calculated with the given value of volume-based specific heat (&#961;cp), which can be obtained from calibration, noncontact photo-thermal technique or measuring the density and specific heat separately. In this work, human head hair samples are used to show how to set up the experiment, process the experimental data, and subtract the effect of parasitic conduction and radiative losses.

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials.

一次元固体材料の熱輸送のキャラクタリゼーション

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials, including ...

工学

Ultrasound Velocity Measurement in a Liquid Metal Electrode

A growing number of electrochemical technologies depend on fluid flow, and often that fluid is opaque. Measuring the flow of an opaque fluid is inherently more difficult than measuring the flow of a transparent fluid, since optical methods are not applicable. Ultrasound can be used to measure the velocity of an opaque fluid, not only at isolated points, but at hundreds or thousands of points arrayed along lines, with good temporal resolution. When applied to a liquid metal electrode, ultrasound velocimetry involves additional challenges: high temperature, chemical activity, and electrical conductivity. Here we describe the experimental apparatus and methods that overcome these challenges and allow the measurement of flow in a liquid metal electrode, as it conducts current, at operating temperature. Temperature is regulated within &#177;2 &#176;C using a Proportional-Integral-Derivative (PID) controller that powers a custom-built furnace. Chemical activity is managed by choosing vessel materials carefully and enclosing the experimental setup in an argon-filled glovebox. Finally, unintended electrical paths are carefully prevented. An automated system logs control settings and experimental measurements, using hardware trigger signals to synchronize devices. This apparatus and these methods can produce measurements that are impossible with other techniques, and allow optimization and control of electrochemical technologies like liquid metal batteries.

Ultrasound velocimetry is used to study mixing by fluid flow in liquid metal electrodes. The focus of this manuscript is to illustrate the methods used for making precise, spatially-resolved ultrasound measurements while limiting oxidation and controlling and monitoring temperature, applied current, and the heater power being supplied.

液体金属電極中の超音波速度計測

A growing number of electrochemical technologies depend on fluid flow, and often that fluid is opaque. Measuring the flow of an opaque fluid is inherently ...

Measurement of Vibration Detection Threshold and Tactile Spatial Acuity in Human Subjects

Tests that allow the precise determination of psychophysical thresholds for vibration and grating orientation provide valuable information about mechanosensory function that are relevant for clinical diagnosis as well as for basic research. Here, we describe two psychophysical tests designed to determine the vibration detection threshold (automated system) and tactile spatial acuity (handheld device). Both procedures implement a two-interval forced-choice and a transformed-rule up and down experimental paradigm. These tests have been used to obtain mechanosensory profiles for individuals from distinct human cohorts such as twins or people with sensorineural deafness.

Here, we present protocols to determine vibration detection thresholds and tactile acuity using psychophysical methods in man.

ヒト対象における振動検出しきい値と触覚空間視力の測定

Tests that allow the precise determination of psychophysical thresholds for vibration and grating orientation provide valuable information about ...

行動学

Experiments on Ultrasonic Lubrication Using a Piezoelectrically-assisted Tribometer and Optical Profilometer

Friction and wear are detrimental to engineered systems. Ultrasonic lubrication is achieved when the interface between two sliding surfaces is vibrated at a frequency above the acoustic range (20 kHz). As a solid-state technology, ultrasonic lubrication can be used where conventional lubricants are unfeasible or undesirable. Further, ultrasonic lubrication allows for electrical modulation of the effective friction coefficient between two sliding surfaces. This property enables adaptive systems that modify their frictional state and associated dynamic response as the operating conditions change. Surface wear can also be reduced through ultrasonic lubrication. We developed a protocol to investigate the dependence of friction force reduction and wear reduction on the linear sliding velocity between ultrasonically lubricated surfaces. A pin-on-disc tribometer was built which differs from commercial units in that a piezoelectric stack is used to vibrate the pin at 22 kHz normal to the rotating disc surface. Friction and wear metrics including effective friction force, volume loss, and surface roughness are measured without and with ultrasonic vibrations at a constant pressure of 1 to 4 MPa and three different sliding velocities: 20.3, 40.6, and 87 mm/sec. An optical profilometer is utilized to characterize the wear surfaces. The effective friction force is reduced by 62% at 20.3 mm/sec. Consistently with existing theories for ultrasonic lubrication, the percent reduction in friction force diminishes with increasing speed, down to 29% friction force reduction at 87 mm/sec. Wear reduction remains essentially constant (49%) at the three speeds considered.

We present a protocol for using a piezoelectrically-assisted tribometer and optical profilometer to investigate the dependence of ultrasonic wear and friction reduction on linear velocity, contact pressure, and surface properties.

圧電支援摩擦計と光プロフィルを用いた超音波潤滑の実験

Friction and wear are detrimental to engineered systems. Ultrasonic lubrication is achieved when the interface between two sliding surfaces is vibrated at ...

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

High resolution optical spectroscopy methods are demanding in terms of either technology, equipment, complexity, time or a combination of these. Here we demonstrate an optical spectroscopy method that is capable of resolving spectral features beyond that of the spin fine structure and homogeneous linewidth of single quantum dots (QDs) using a standard, easy-to-use spectrometer setup. This method incorporates both laser and photoluminescence spectroscopy, combining the advantage of laser line-width limited resolution with multi-channel photoluminescence detection. Such a scheme allows for considerable improvement of resolution over that of a common single-stage spectrometer. The method uses phonons to assist in the measurement of the photoluminescence of a single quantum dot after resonant excitation of its ground state transition. The phonon&#39;s energy difference allows one to separate and filter out the laser light exciting the quantum dot. An advantageous feature of this method is its straight forward integration into standard spectroscopy setups, which are accessible to most researchers.

The manuscript describes a method of phonon-assisted quasi-resonant fluorescence spectroscopy that incorporates both laser-limited resolution and photoluminescence (PL) spectroscopy. This method utilizes optical phonons to provide linewidth-limited resolution spectra of atom-like semiconductor structures in the energy domain. The method is also easily realized with a single spectrometer optical spectroscopy setup.

高解像度フォノンアシスト準共鳴蛍光分光

High resolution optical spectroscopy methods are demanding in terms of either technology, equipment, complexity, time or a combination of these. Here we ...

Fabrication and Characterization of Superconducting Resonators

Superconducting microwave resonators are of interest for a wide range of applications, including for their use as microwave kinetic inductance detectors (MKIDs) for the detection of faint astrophysical signatures, as well as for quantum computing applications and materials characterization. In this paper, procedures are presented for the fabrication and characterization of thin-film superconducting microwave resonators. The fabrication methodology allows for the realization of superconducting transmission-line resonators with features on both sides of an atomically smooth single-crystal silicon dielectric. This work describes the procedure for the installation of resonator devices into a cryogenic microwave testbed and for cool-down below the superconducting transition temperature. The set-up of the cryogenic microwave testbed allows one to do careful measurements of the complex microwave transmission of these resonator devices, enabling the extraction of the properties of the superconducting lines and dielectric substrate (e.g., internal quality factors, loss and kinetic inductance fractions), which are important for device design and performance.

Superconducting microwave resonators are of interest for detection of light, quantum computing applications and materials characterization. This work presents a detailed procedure for fabrication and characterization of superconducting microwave resonator scattering parameters.

超伝導共振器の作製と評価

Superconducting microwave resonators are of interest for a wide range of applications, including for their use as microwave kinetic inductance detectors ...

Wideband Optical Detector of Ultrasound for Medical Imaging Applications

Optical sensors of ultrasound are a promising alternative to piezoelectric techniques, as has been recently demonstrated in the field of optoacoustic imaging. In medical applications, one of the major limitations of optical sensing technology is its susceptibility to environmental conditions, e.g. changes in pressure and temperature, which may saturate the detection. Additionally, the clinical environment often imposes stringent limits on the size and robustness of the sensor. In this work, the combination of pulse interferometry and fiber-based optical sensing is demonstrated for ultrasound detection. Pulse interferometry enables robust performance of the readout system in the presence of rapid variations in the environmental conditions, whereas the use of all-fiber technology leads to a mechanically flexible sensing element compatible with highly demanding medical applications such as intravascular imaging. In order to achieve a short sensor length, a pi-phase-shifted fiber Bragg grating is used, which acts as a resonator trapping light over an effective length of 350 &#181;m. To enable high bandwidth, the sensor is used for sideway detection of ultrasound, which is highly beneficial in circumferential imaging geometries such as intravascular imaging. An optoacoustic imaging setup is used to determine the response of the sensor for acoustic point sources at different positions.

Optical detection of ultrasound is impractical in many imaging scenarios because it often requires stable environmental conditions. We demonstrate an optical technique for ultrasound sensing in volatile environments with miniaturization and sensitivity levels appropriate for optoacoustic imaging in restrictive scenarios, e.g. intravascular applications.

医療画像処理アプリケーションのための超音波の広帯域光検出器

Optical sensors of ultrasound are a promising alternative to piezoelectric techniques, as has been recently demonstrated in the field of optoacoustic ...

生物工学

Ultrasonic Fatigue Testing in the Tension-Compression Mode

Ultrasonic fatigue testing is one of a few methods which allow investigating fatigue properties in the ultra-high cycle region. The method is based on exposing the specimen to longitudinal vibrations on its resonance frequency close to 20 kHz. With use of this method, it is possible to significantly decrease the time required for the test, when compared to conventional testing devices usually working at frequencies under 200 Hz. It is also used to simulate loading of material during operation in high speed conditions, such as those experienced by components of jet engines or car turbo pumps. It is necessary to operate only in the high and ultra-high cycle region, due to the possibility of extremely high deformation rates, which can have a significant influence on the test results. Specimen shape and dimensions have to be carefully selected and calculated to fulfill the resonance condition of the ultrasonic system; thus, it is not possible to test the full components or specimens of arbitrary shape. Before each test, it is necessary to harmonize the specimen with the frequency of the ultrasonic system to compensate for deviations of the real shape from the ideal one. It is not possible to run a test until a total fracture of the specimen, since the test is automatically terminated after initiation and propagation of the crack to a certain length, when the stiffness of the system changes enough to shift the system out of the resonance frequency. This manuscript describes the process of evaluation of materials' fatigue properties at high-frequency ultrasonic fatigue loading with use of mechanical resonance at a frequency close to 20 kHz. The protocol includes a detailed description of all steps required for a correct test, including specimen design, stress calculation, harmonizing with the resonance frequency, performing the test, and final static fracture.

A protocol for ultrasonic fatigue testing in the high and ultra-high cycle region in axial tension-compression loading mode.

超音波疲労引張圧縮モードでのテスト

Ultrasonic fatigue testing is one of a few methods which allow investigating fatigue properties in the ultra-high cycle region. The method is based on ...

Fabrication and Characterization of Thickness Mode Piezoelectric Devices for Atomization and Acoustofluidics

We present a technique to fabricate simple thickness mode piezoelectric devices using lithium niobate (LN). Such devices have been shown to atomize liquid more efficiently, in terms of &#64258;ow rate per power input, than those that rely on Rayleigh waves and other modes of vibration in LN or lead zirconate titanate (PZT). The complete device is composed of a transducer, a transducer holder, and a &#64258;uid supply system. The fundamentals of acoustic liquid atomization are not well known, so techniques to characterize the devices and to study the phenomena are also described. Laser Doppler vibrometry (LDV) provides vibration information essential in comparing acoustic transducers and, in this case, indicates whether a device will perform well in thickness vibration. It can also be used to &#64257;nd the resonance frequency of the device, though this information is obtained more quickly via impedance analysis. Continuous &#64258;uid atomization, as an example application, requires careful &#64258;uid flow control, and we present such a method with high-speed imaging and droplet size distribution measurements via laser scattering.

Fabrication of piezoelectric thickness mode transducers via direct current sputtering of plate electrodes on lithium niobate is described. Additionally, reliable operation is achieved with a transducer holder and &#64258;uid supply system and characterization is demonstrated via impedance analysis, laser doppler vibrometry, high-speed imaging, and droplet size distribution using laser scattering.

微粒化およびアユースト流体のための厚さモード圧電デバイスの作製と特性

We present a technique to fabricate simple thickness mode piezoelectric devices using lithium niobate (LN). Such devices have been shown to atomize liquid ...

<meta charset="utf8"></head><body>3Dプリントポリマーメタマテリアルの粘弾性特性の特性評価

Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing

Viscoelastic behavior can be beneficial in enhancing the unprecedented dynamics of polymer metamaterials or, in contrast, negatively impacting their wave control mechanisms. It is, therefore, crucial to properly characterize the viscoelastic properties of a polymer metamaterial at its working frequencies to understand viscoelastic effects. However, the viscoelasticity of polymers is a complex phenomenon, and the data on storage and loss moduli at ultrasonic frequencies are extremely limited, especially for additively manufactured polymers. This work presents a protocol to experimentally characterize the viscoelastic properties of additively manufactured polymers and to use them in the numerical analysis of polymer metamaterials. Specifically, the protocol includes the description of the manufacturing process, experimental procedures to measure the thermal, viscoelastic, and mechanical properties of additively manufactured polymers, and an approach to use these properties in finite-element simulations of the metamaterial dynamics. The numerical results are validated in ultrasonic transmission tests. To exemplify the protocol, the analysis is focused on acrylonitrile butadiene styrene (ABS) and aims at characterizing the dynamic behavior of a simple metamaterial made from it by using fused deposition modeling (FDM) three-dimensional (3D) printing. The proposed protocol will be helpful for many researchers to estimate viscous losses in 3D-printed polymer elastic metamaterials that will improve the understanding of material-property relations for viscoelastic metamaterials and eventually stimulate the use of 3D-printed polymer metamaterial parts in various applications.

<meta charset="utf8"></head><body>アディティブマニュファクチャリングによって生成される散逸性弾性メタマテリアルの特性評価

Additively manufactured polymers have been widely used for producing elastic metamaterials. The viscoelastic behavior of these polymers at ultrasonic frequencies remains, however, poorly studied. This study reports a protocol to estimate the viscoelastic properties of 3D-printed polymers and show how to use them to analyze the metamaterial dynamics.

アディティブマニュファクチャリングによって生成される散逸性弾性メタマテリアルの特性評価 

Viscoelastic behavior can be beneficial in enhancing the unprecedented dynamics of polymer metamaterials or, in contrast, negatively impacting their wave ...