この作品は、ウェイクフォレスト化学部門とエネルギー、環境、および持続可能性（CEES）のためのウェイクフォレストセンターによってサポートされていました。私たちは、チャールズ・ムーニーとSEM画像と支援のためのノースカロライナ州立大学の分析機器施設に感謝します。

1.準備キセロゲルペレット<ol><li>ジェル合成<ol><li> 500mLビーカーに25ミリメートルの磁気撹拌棒及び脱イオン水113ミリリットルを追加します。磁気渦を形成しない最高の速度で脱イオン水をかき混ぜます。 </li><li>ゆっくり少しずつの脱イオン水に無水塩化ジルコニウムの13.05グラム（0.056モル）を加えます。無水塩化ジルコニウムの全てが溶解した後、溶液にグルコースの53.29グラム（0.296モル）を加えます。 </li><li>グルコースの全てが溶液中に溶解した後、溶液に硝酸イットリウム六水和物の3.73グラム（0.01モル）を加えます。 〜700rpmで磁気攪拌速度を増加させ、その溶液中に溶解させるために硝酸イットリウム六水和物のすべてをお待ちしております。 </li><li>溶液にプロピレンオキシドの42ミリリットルを加えます。プロピレンオキシドは、水溶液と混合するため〜700rpmで撹拌し続けます。プロピレンオキサイド水溶液（〜10秒）と混合された後、磁気撹拌Tを減少させますO〜150rpmで。 </li><li>磁気撹拌棒は、ゲルの形成による移動を停止するまで撹拌し続けます。ゲルは、典型的には3分以内に形成します。 メモ：脱イオン水に無水塩化ジルコニウムを追加すると、非常に発熱反応であり、それはあまりにも急速に添加した場合、無水塩化ジルコニウムプルームう。 セクション1.1で提供製剤。全金属（ジルコニウム+イットリウム）4.5のモル比のグルコースに相当する：1。 1、2.25：1、および4.5：代表的な結果セクションは0の全金属のモル比へのグルコースのデータを含む1。製剤中のグルコースの量だけ溶液中のグルコースの溶解性によって制限されます。参考のために、20℃の水におけるグルコースの最大溶解度は47.8重量％です。 15 </li></ol></li><li>高齢化とゲルの洗浄<ol><li>しっかりパラフィルムとゲルを含むビーカーを覆い、室温で覆われたビーカーを残すことによって24時間、年齢、それをしましょう。 </li><li>ビーカーからカバーを外し、ゲルの上に液体をデカント。 </li><li>しっかりパラフィルム付きビーカーを覆い、ゲルを含有するビーカーに無水エタノール300 mLを加え、24時間室温で覆われたビーカーを残します。 </li><li> 72時間の全期間にわたって3つのエタノール洗浄液の合計を繰り返しステップ1.2.3さらに2回。 </li></ol></li><li>キセロゲルにゲルを乾燥<ol><li>ビーカーからゲルを除去し、実験室用スパチュラを用いて（上部外径24センチメートル）2Lの磁製蒸発皿に置きます。 </li><li>スパチュラで約1cm X 1cmの断片にゲルを破壊し、蒸発皿の表面上の部分を広げます。 </li><li>ゲル片は、1週間またはゲルが乾燥するまで周囲条件下で乾燥させます。それは微粉末に粉砕することができるときにゲルを乾燥考えられます。 </li><li>乳鉢と乳棒で微粉末にキセロゲルのすべてを挽きます。 注：ゲルが乾燥していると、それはありますそれは周囲条件下で乾燥させたので、キセロゲルを検討しました。 </li></ol></li><li>ペレットにキセロゲルを押します<ol><li> 13ミリメートルの直径を有する円筒形ペレットプレスのダイにキセロゲル粉末1gを置き。 </li><li>油圧プレスを用いて、ペレットにキセロゲルゲルを押して90秒間力の22キロニュートンを適用します。 </li><li>ゆっくりプレスによって加えられた力を解放します。ゆっくりペレットダイのうちのペレットを取り出した後、慎重にペレットを削除します。 </li></ol></li></ol> 2.不活性雰囲気中でキセロゲルペレットを焼結<ol><li>アルミナ又はイットリア安定化ジルコニア板上にキセロゲルペレットを配置し、管状炉の中央にプレートをロードします。 </li><li>三分の一分当たりの作業管の体積の割合でアルゴンを流します。これは、750ミリリットルのアルゴン流量に相当・分-1本研究で用い作業管用。ヒュームフードにガス出口ベント。 </li><li>少なくとも15分間Bのアルゴンの流れチューブ炉を加熱するために始めEFORE。 </li><li>連続的に一定速度でアルゴンを流しながら、プログラムに従って加熱スケジュールにチューブ炉温度制御： <ol><li>室温で15分間保持します。 </li><li> 5℃のランプ速度で850℃まで加熱・分-1。 </li><li> 2℃のランプ速度で所望の焼結温度まで加熱・分-1。 </li><li> 2時間のための所望の焼結温度で保持します。 </li><li> 2°Cのランプ速度で850°C・分-1にクール。 </li><li> 5℃・分-1のランプ速度で室温まで冷却。 </li></ol></li><li>管状炉は、セクション2.3で提供スケジュールに従って加熱されていることをプログラムし、ダブルチェックを開始します。 </li><li>加熱プログラムが完了した後、チューブ炉からペレットを削除します。 </li></ol> 3.カーボンテンプレートの濃度を測定します<ol><li>外〜50mgのピースをカットユーティリティナイフで焼結キセロゲルペレットと瑪瑙乳鉢と乳棒で微粉末にそれを挽きます。 </li><li>熱重量分析のためにアルミナ試料カップに微粉末の代わり〜50ミリグラム。 </li><li>熱重量分析（TGA）を用いて、10℃の速度で試料を加熱・分-1周囲温度から100ミリリットルの速度で試料上に空気を流しながら1200℃まで・分-1。 </li><li> 〜350℃、〜700°Cの間で発生する重量のパーセント変化を計算します。この重量％は、試料中の全炭素含有量に相当します。 注：重量増加は、700°Cの範囲に350°Cで発生した場合、炭化物相が形成されており、炭素含有量の計算はより複雑です。このような場合のために、文献に記載された計算を参照してください。 14個の炭素元素分析は、炭素含有量は、TGA測定から計算することができることを確認するために使用されてきました。 </li></ol>カーボンテンプレートの除去による高表面積YSZ足場を準備4 <ol><li>アルミナ坩堝中の焼結キセロゲルペレットを置きます。 </li><li> 2時間700℃で箱形炉内に坩堝を置き。 </li><li>慎重にステンレス鋼のるつぼトングでボックス炉から熱いるつぼを削除し、それが多孔質、白YSZ足場を取り外す前に、1時間室温まで冷却することができます。 </li></ol>

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インサイチュ炭素テンプレートアプローチでこれにより、一つは従来のセラミック足場焼結温度で、混合金属酸化物でnanomorphologyを作成して保存することができます。得られた表面領域は、最大80倍、従来の焼結足場よりも高く、最大4倍の複雑な蒸着技術によって製造足場よりも高いです。 14プロピレンオキシドグルコースゲルシステムは、1つの系統的に10体?...

固体酸化物燃料電池（SOFC）は、クリーンな電力の効率的な生成のための代替エネルギー変換技術として非常に有望です。 1つのかなりの進歩は、この技術の研究開発に行われています。しかし、電極性能の向上が、まだ信頼性の高い実用化を達成するために必要とされています。電極は、多くの場合、足場表面上に装飾された電気触媒粒子を有する多孔質セラミック足場を含みます。研究の大きな体は、パフォーマンス、2、3、4、5、6、7、8を増大させるために電気触媒粒子の表面積を増加させることに集中してきたが、足場の表面積を増大させるにはほとんど研究があります。足場の表面を増やしますそれらは、高温で焼結されているので、面積は1100°Cで1500°Cに、困難です。 伝統的な焼結処理の足場は、典型的には0.1〜1メートル2・G -1の比表面積を有します。 8、9、10、11足場の表面積を増大させるには、いくつかの報告があります。あるケースでは、伝統的に、焼結足場の表面積は2 m 2で・G -1の比表面積を達成する、フッ酸を用いて溶解し、足場の表面の析出によって強化されました。別に図12に示すように 、高い温度が20メートル2・G -1の比表面積を達成する、パルスレーザー堆積法を使用することによって完全に回避されました。 13私たちの技術の発展の理論的根拠は、低コストの製造を作成することでした前例のない足場表面積を提供し、プロセスを容易に採用することができるように、伝統的な焼結温度を使用するプロセス。ここで報告された技術では、足場の表面領域80メートル2まで・G -1と伝統的な焼結温度で処理しながら実証されています。 14 我々の研究は、主にSOFC電極エンジニアリングによって動機付けられているが、この技術は、より広く適用他の分野やアプリケーションにあります。一般に、in situで炭素テンプレート方法は、ナノ構造、粉末または多孔性足場状の高表面積混合金属セラミック材料を製造することができる柔軟なアプローチです。これは、混合金属、セラミック組成物は、表面積、多孔度、および孔サイズは全て系統的に調整することができるという点で柔軟です。高温は、多くの場合、混合金属セラミックにおける所望の相を形成するのに必要な、このアプローチは、Wセラミックnanomorphologyを保持しています1は、本質的に任意の処理温度を選択することができhile。 この方法は、十分に金属イオンと有機含有無機の比の化学量論を定義すると、ハイブリッド無機 - 有機プロピレンオキサイド系ゲルの合成を含みます。ゲルをキセロゲルを形成するために、周囲条件下で乾燥させます。キセロゲルを所望の温度でアルゴン雰囲気中で焼結されます。加熱すると、有機成分は、焼結の期間ままその場で炭素テンプレートを残す分解する。カーボンテンプレートは、その後、ナノ構造、高表面積セラミック、その結果、空気中の低温酸化によって除去されます。

<table><tbody><tr><td>Zirconium(IV) chloride, 99.5+%</td><td>Alfa Aesar</td><td>12104</td><td>Air sensitive</td></tr><tr><td>Yttium(III) nitrate hexadydrate, 99.9%</td><td>Alfa Aesar</td><td>12898</td><td>Oxidizer</td></tr><tr><td>D+ Glucose Anhydrous, &amp;ge;99.5%</td><td>US Biological Life Sciences</td><td>G3050</td><td></td></tr><tr><td>(&amp;plusmn;)-Propylene Oxide, &amp;ge;99%</td><td>Sigma Aldrich</td><td>110205</td><td>Extremely flammable</td></tr><tr><td>Ethanol 200 Proof</td><td>Decon Laboratories, Inc.</td><td>2716GEA</td><td></td></tr><tr><td>Argon, 99.997%</td><td>Airgas</td><td>AR 300</td><td>Industrial grade</td></tr></tbody></table>

high temperature fabrication of nanostructured yttria-stabilized-zirconia (ysz) scaffolds by in situ carbon templating xerogels

調整可能な比表面積を有する足場最大80 m 2で・G -1 -私たちは（92モル％ジルコニアYSZ、8モル％のイットリア）多孔質、ナノ構造イットリア安定化ジルコニアの高温製造のための方法を実証します。ジルコニウム塩、イットリウム塩、およびグルコースの水溶液はゲルを形成するために、プロピレンオキシド（PO）と混合されます。ゲルをキセロゲルを形成するために、周囲条件下で乾燥させます。キセロゲルはペレットに圧縮した後、アルゴン雰囲気中で焼結されます。焼結中、YSZセラミック相が形成と有機成分は、非晶質炭素を残し、分解する。 その場で形成された炭素は、焼結温度で高表面積YSZのnanomorphologyを維持し、ハード鋳型として働きます。炭素は、その後、多孔質、ナノ構造YSZ足場、その結果、低い温度の空気中での酸化によって除去されます。炭素テンプレートの濃度と最終的なスカフォールド表面積が系統的であることができますLYゲル合成中のグルコース濃度を変えることによって調整。カーボン鋳型濃度は、表面積および細孔サイズ分布は、物理吸着測定により測定した熱重量分析（TGA）を用いて定量し、および形態は、走査型電子顕微鏡（SEM）を用いて特徴付けました。相純度及び結晶子サイズは、X線回折（XRD）を用いて決定しました。この製造手法は、新規な、セラミックベースの電気化学エネルギー変換用途のために前例のない足場の表面領域とnanomorphologiesを実現するための柔軟なプラットフォーム、 例えば固体酸化物燃料電池（SOFC）の電極を提供します。

以前にCottam らによって報告されているように相純度は、X線回折（XRD）により確認しました。カーボン鋳型濃度の関数として14 YSZ足場比表面積は、 図1に示されています。濃度は、焼結キセロゲルペレット中の全固形分の体積パーセントとして示されています。カーボン鋳型濃度を系統的ゲル製剤中のグルコース濃度の増加?...

Watch this Scientific Journal Video about High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels at JoVE.com

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels

1000℃及び1400℃の間の温度で多孔質、ナノ構造イットリア安定化ジルコニア（YSZ）足場を製造するためのプロトコルが提供されます。

によってナノ構造イットリア安定化ジルコニア（YSZ）足場の高温製作<em&gt;その場での</em&gt;カーボンテンプレート化キセロゲル

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) ...

high-temperature-fabrication-nanostructured-yttria-stabilized

Research

JoVE Journal

Engineering

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia (YSZ) Scaffolds by In Situ Carbon Templating Xerogels

10.5K ビュー.  Wake Forest University.  1000℃及び1400℃の間の温度で多孔質、ナノ構造イットリア安定化ジルコニア（YSZ）足場を製造するためのプロトコルが提供されます。 

ビデオ: High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels

Fabrication, Densification, and Replica Molding of 3D Carbon Nanotube Microstructures

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip devices, and their applications. In particular, capabilities for cost-effective fabrication of polymer microstructures were transformed by the advent of soft lithography and other micromolding techniques 1, 2, and this led a revolution in applications of microfabrication to biomedical engineering and biology. Nevertheless, it remains challenging to fabricate microstructures with well-defined nanoscale surface textures, and to fabricate arbitrary 3D shapes at the micro-scale. Robustness of master molds and maintenance of shape integrity is especially important to achieve high fidelity replication of complex structures and preserving their nanoscale surface texture. The combination of hierarchical textures, and heterogeneous shapes, is a profound challenge to existing microfabrication methods that largely rely upon top-down etching using fixed mask templates. On the other hand, the bottom-up synthesis of nanostructures such as nanotubes and nanowires can offer new capabilities to microfabrication, in particular by taking advantage of the collective self-organization of nanostructures, and local control of their growth behavior with respect to microfabricated patterns. 
Our goal is to introduce vertically aligned carbon nanotubes (CNTs), which we refer to as CNT "forests", as a new microfabrication material. We present details of a suite of related methods recently developed by our group: fabrication of CNT forest microstructures by thermal CVD from lithographically patterned catalyst thin films; self-directed elastocapillary densification of CNT microstructures; and replica molding of polymer microstructures using CNT composite master molds. In particular, our work shows that self-directed capillary densification ("capillary forming"), which is performed by condensation of a solvent onto the substrate with CNT microstructures, significantly increases the packing density of CNTs. This process enables directed transformation of vertical CNT microstructures into straight, inclined, and twisted shapes, which have robust mechanical properties exceeding those of typical microfabrication polymers. This in turn enables formation of nanocomposite CNT master molds by capillary-driven infiltration of polymers. The replica structures exhibit the anisotropic nanoscale texture of the aligned CNTs, and can have walls with sub-micron thickness and aspect ratios exceeding 50:1. Integration of CNT microstructures in fabrication offers further opportunity to exploit the electrical and thermal properties of CNTs, and diverse capabilities for chemical and biochemical functionalization 3.

We present methods for fabrication of patterned microstructures of vertically aligned carbon nanotubes (CNTs), and their use as master molds for production of polymer microstructures with organized nanoscale surface texture. The CNT forests are densified by condensation of solvent onto the substrate, which significantly increases their packing density and enables self-directed formation of 3D shapes.

製造、ち密化、および3Dカーボンナノチューブの微細構造のレプリカ成形

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip ...

工学

Preparation and Reactivity of Gasless Nanostructured Energetic Materials

High-Energy Ball Milling (HEBM) is a ball milling process where a powder mixture placed in the ball mill is subjected to high-energy collisions from the balls. Among other applications, it is a versatile technique that allows for effective preparation of gasless reactive nanostructured materials with high energy density per volume (Ni+Al, Ta+C, Ti+C). The structural transformations of reactive media, which take place during HEBM, define the reaction mechanism in the produced energetic&#160;composites. Varying the processing conditions permits fine tuning of the milling-induced microstructures of the fabricated composite particles. In turn, the reactivity, i.e., self-ignition temperature, ignition delay time, as well as reaction kinetics, of high energy density materials depends on its microstructure. Analysis of the milling-induced microstructures suggests that the formation of fresh oxygen-free intimate high surface area contacts between the reagents is responsible for the enhancement of their reactivity. This manifests itself in a reduction of ignition temperature and delay time, an increased rate of chemical reaction, and an overall decrease of the effective activation energy of the reaction. The protocol provides a detailed description for the preparation of reactive nanocomposites with tailored microstructure using short-term HEBM method. It also describes a high-speed thermal imaging technique to determine the ignition/combustion characteristics of the energetic materials. The protocol can be adapted to preparation and characterization of a variety of nanostructured energetic composites.

This protocol describes the preparation of gasless nanostructured energetic materials (Ni+Al, Ta+C, Ti+C) using the short-term high-energy ball milling (HEBM) technique. It also describes a high-speed thermal imaging method to study the reactivity of mechanically fabricated nanocomposites. These protocols can be extended to other reactive nanostructured energetic materials.

Gaslessナノエネルギー物質の調製と反応性

High-Energy Ball Milling (HEBM) is a ball milling process where a powder mixture placed in the ball mill is subjected to high-energy collisions from the ...

Formation of Thick Dense Yttrium Iron Garnet Films Using Aerosol Deposition

Aerosol deposition (AD) is a thick-film deposition process that can produce layers up to several hundred micrometers thick with densities greater than 95% of the bulk. The primary advantage of AD is that the deposition takes place entirely at ambient temperature; thereby enabling film growth in material systems with disparate melting temperatures. This report describes in detail the processing steps for preparing the powder and for performing AD using the custom-built system. Representative characterization results are presented from scanning electron microscopy, profilometry, and ferromagnetic resonance for films grown in this system. As a representative overview of the capabilities of the system, focus is given to a sample produced following the described protocol and system setup. Results indicate that this system can successfully deposit 11 &#181;m thick yttrium iron garnet films that are &#160;&#62; 90% of the bulk density during a single 5 min deposition run. A discussion of methods to afford better control of the aerosol and particle selection for improved thickness and roughness variations in the film is provided.

This report describes the use of a custom-built system to perform aerosol deposition of thick films of yttrium iron garnet onto sapphire substrates at RT. The deposited films are characterized using scanning electron microscopy, profilometry, and ferromagnetic resonance to give a representative overview of the capabilities of the technique.

エアロゾルデポジション法を用いて厚い高密度イットリウム鉄ガーネット膜の形成

Aerosol deposition (AD) is a thick-film deposition process that can produce layers up to several hundred micrometers thick with densities greater than 95% ...

Aerosol-assisted Chemical Vapor Deposition of Metal Oxide Structures: Zinc Oxide Rods

Whilst columnar zinc oxide (ZnO) structures in the form of rods or wires have been synthesized previously by different liquid- or vapor-phase routes, their high cost production and/or incompatibility with microfabrication technologies, due to the use of pre-deposited catalyst-seeds and/or high processing temperatures exceeding 900 &#176;C, represent a drawback for a widespread use of these methods. Here, however, we report the synthesis of ZnO rods via a non-catalyzed vapor-solid mechanism enabled by using an aerosol-assisted chemical vapor deposition (CVD) method at 400 &#176;C with zinc chloride (ZnCl2) as the precursor and ethanol as the carrier solvent. This method provides both single-step formation of ZnO rods and the possibility of their direct integration with various substrate types, including silicon, silicon-based micromachined platforms, quartz, or high heat resistant polymers. This potentially facilitates the use of this method at a large-scale, due to its compatibility with state-of-the-art microfabrication processes for device manufacture. This report also describes the properties of these structures (e.g., morphology, crystalline phase, optical band gap, chemical composition, electrical resistance) and validates its gas sensing functionality towards carbon monoxide.

Columnar zinc oxide structures in the form of rods are synthesized via aerosol-assisted chemical vapor deposition without the use of pre-deposited catalyst-seed particles. This method is scalable and compatible with various substrates based on either silicon, quartz or polymers.

エアロゾルによる金属酸化物の構造の化学蒸着: 酸化亜鉛棒

Whilst columnar zinc oxide (ZnO) structures in the form of rods or wires have been synthesized previously by different liquid- or vapor-phase routes, ...

化学

Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain

Barium titanate (BaTiO3, hereafter BT) is an established ferroelectric material first discovered in the 1940s and still widely used because of its well-balanced ferroelectricity, piezoelectricity, and dielectric constant. In addition, BT does not contain any toxic elements. Therefore, it is considered to be an eco-friendly material, which has attracted considerable interest as a replacement for lead zirconate titanate (PZT). However, bulk BT loses its ferroelectricity at approximately 130 &#176;C, thus, it cannot be used at high temperatures. Because of the growing demand for high-temperature ferroelectric materials, it is important to enhance the thermal stability of ferroelectricity in BT. In previous studies, strain originating from the lattice mismatch at hetero-interfaces has been used. However, the sample preparation in this approach requires complicated and expensive physical processes, which are undesirable for practical applications.
In this study, we propose a chemical synthesis of a porous material as an alternative means of introducing strain. We synthesized a porous BT thin film using a surfactant-assisted sol-gel method, in which self-assembled amphipathic surfactant micelles were used as an organic template. Through a series of studies, we clarified that the introduction of pores had a similar effect on distorting the BT crystal lattice, to that of a hetero-interface, leading to the enhancement and stabilization of ferroelectricity. Owing to its simplicity and cost effectiveness, this fabrication process has considerable advantages over conventional methods.

Here, we present a protocol for the synthesis of porous barium titanate (BaTiO3) thin film by a surfactant-assisted sol-gel method, in which self-assembled amphipathic surfactant micelles are used as an organic template.

化学合成チタン酸バリウム多孔質セラミックス薄膜の気孔率誘起歪による強誘電相の熱安定化

Barium titanate (BaTiO3, hereafter BT) is an established ferroelectric material first discovered in the 1940s and still widely used because of its ...

Multi-material Ceramic-Based Components &#8211; Additive Manufacturing of Black-and-white Zirconia Components by Thermoplastic 3D-Printing (CerAM - T3DP)

To combine the benefits of Additive Manufacturing (AM) with the benefits of Functionally Graded Materials (FGM) to ceramic-based 4D components (three dimensions for the geometry and one degree of freedom concerning the material properties at each position) the Thermoplastic 3D-Printing (CerAM -&#160;T3DP) was developed. It is a direct AM technology which allows the AM of multi-material components. To demonstrate the advantages of this technology black-and-white zirconia components were additively manufactured and co-sintered defect-free.
Two different pairs of black and white zirconia powders were used to prepare different thermoplastic suspensions. Appropriate dispensing parameters were investigated to manufacture single-material test components and adjusted for the additive manufacturing of multi-color zirconia components.

Here we describe a protocol for additively manufacturing black-and-white zirconia components by Thermoplastic 3D-Printing (CerAM -&#160;T3DP) and co-sintering defect-free.

マルチ材料セラミック ベースのコンポーネント-添加熱可塑性 3 D 印刷 (セラム - T3DP) 白黒ジルコニア部品の製造

To combine the benefits of Additive Manufacturing (AM) with the benefits of Functionally Graded Materials (FGM) to ceramic-based 4D components (three ...

Fused Filament Fabrication (FFF) of Metal-Ceramic Components

Technical ceramics are widely used for industrial and research applications, as well as for consumer goods. Today, the demand for complex geometries with diverse customization options and favorable production methods is increasing continuously. With fused filament fabrication (FFF), it is possible to produce large and complex components quickly with high material efficiency. In FFF, a continuous thermoplastic filament is melted in a heated nozzle and deposited below. The computer-controlled print head is moved in order to build up the desired shape layer by layer. Investigations regarding printing of metals or ceramics are increasing more and more in research and industry. This study focuses on additive manufacturing (AM) with a multi-material approach to combine a metal (stainless steel) with a technical ceramic (zirconia: ZrO2). Combining these materials offers a broad variety of applications due to their different electrical and mechanical properties. The paper shows the main issues in preparation of the material and feedstock, device development, and printing of these composites.

Fused Filament Fabrication FFF of Metal-Ceramic Components

This study shows multi-material additive manufacturing (AM) using fused filament fabrication (FFF) of stainless steel and zirconia.

金属-セラミック部品の溶融フィラメント製作 (FFF)

Technical ceramics are widely used for industrial and research applications, as well as for consumer goods. Today, the demand for complex geometries with ...

Additive Manufacturing of Functionally Graded Ceramic Materials by Stereolithography

An additive manufacturing technology is applied to obtain functionally graded ceramic parts. This technology, based on digital light processing/stereolithography, is developed within the scope of the CerAMfacturing European research project. A three-dimensional (3-D) hemi-maxillary bone-like structure is 3-D printed using custom aluminum oxide polymeric mixtures. The powders and mixtures are fully analyzed in terms of rheological behavior in order to ensure proper material handling during the printing process. The possibility to print functionally graded materials using the Admaflex technology is explained in this document. Field-emission scanning electron microscopy (FESEM) show that the sintered aluminum oxide ceramic part has a porosity lower than 1% and no remainder of the original layered structure is found after analysis.

This manuscript describes the processing of single multifunctional ceramic components (e.g., combinations of dense-porous structures) additively manufactured by stereolithography.

光造形法による傾斜機能セラミック材料の添加剤の製造

An additive manufacturing technology is applied to obtain functionally graded ceramic parts. This technology, based on digital light ...

Fabrication of Mechanically Tunable and Bioactive Metal Scaffolds for Biomedical Applications

Biometal systems have been widely used for biomedical applications, in particular, as load-bearing materials. However, major challenges are high stiffness and low bioactivity of metals. In this study, we have developed a new method towards fabricating a new type of bioactive and mechanically reliable porous metal scaffolds-densified porous Ti scaffolds. The method consists of two fabrication processes, 1) the fabrication of porous Ti scaffolds by dynamic freeze casting, and 2) coating and densification of the porous scaffolds. The dynamic freeze casting method to fabricate porous Ti scaffolds allowed the densification of porous scaffolds by minimizing the chemical contamination and structural defects. The densification process is distinctive for three reasons. First, the densification process is simple, because it requires a control of only one parameter (degree of densification). Second, it is effective, as it achieves mechanical enhancement and sustainable release of biomolecules from porous scaffolds. Third, it has broad applications, as it is also applicable to the fabrication of functionally graded porous scaffolds by spatially varied strain during densification.

Bioactive and mechanically reliable metal scaffolds have been fabricated through a method which consists of two processes, dynamic freeze casting for the fabrication of porous Ti, and coating and densification of the Ti scaffolds. The densification process is simple, effective and applicable to the fabrication of functionally graded scaffolds.

バイオメディカル応用のための機械的に調整可能な生物活性金属スキャフォールドの作製

Biometal systems have been widely used for biomedical applications, in particular, as load-bearing materials. However, major challenges are high stiffness ...

生物工学

Epitaxial Nanostructured &alpha;-Quartz Films on Silicon: From the Material to New Devices

In this work, we show a detailed engineering route of the first piezoelectric nanostructured epitaxial quartz-based microcantilever. We will explain all the steps in the process starting from the material to the device fabrication. The epitaxial growth of &#945;-quartz film on SOI (100) substrate starts with the preparation of a strontium doped silica sol-gel and continues with the deposition of this gel into the SOI substrate in a thin film form using the dip-coating technique under atmospheric conditions at room temperature. Before crystallization of the gel film, nanostructuration is performed onto the film surface by nanoimprint lithography (NIL). Epitaxial film growth is reached at 1000 &#176;C, inducing a perfect crystallization of the patterned gel film. Fabrication of quartz crystal cantilever devices is a four-step process based on microfabrication techniques. The process starts with shaping the quartz surface, and then metal deposition for electrodes follows it. After removing the silicone, the cantilever is released from SOI substrate eliminating SiO2 between silicon and quartz. The device performance is analyzed by non-contact laser vibrometer (LDV) and atomic force microscopy (AFM). Among the different cantilever&#8217;s dimensions included in the fabricated chip, the nanostructured cantilever analyzed in this work exhibited a dimension of 40 &#181;m large and 100 &#181;m long and was fabricated with a 600 nm thick patterned quartz layer (nanopillar diameter and separation distance of 400 nm and 1 &#181;m, respectively) epitaxially grown on a 2 &#181;m thick Si device layer. The&#160;measured&#160;resonance frequency was&#160;267 kHz and the estimated quality factor, Q, of the whole mechanical structure was Q ~ 398 under low vacuum conditions. We observed the voltage-dependent linear displacement of cantilever with both techniques (i.e., AFM contact measurement and LDV). Therefore, proving that these devices can be activated through the indirect piezoelectric effect.

Epitaxial Nanostructured &#945;-Quartz Films on Silicon: From the Material to New Devices

This work presents a detailed protocol for the microfabrication of nanostructured &#945;-quartz cantilever on a Silicon-On-Insulator(SOI) technology substrate starting from the epitaxial growth of quartz film with the dip coating method and then nanostructuration of the thin film via nanoimprint lithography.

シリコン上のエピタキシャルナノ構造α-クオーツフィルム:材料から新しいデバイスへ

In this work, we show a detailed engineering route of the first piezoelectric nanostructured epitaxial quartz-based microcantilever. We will explain all ...

によってナノ構造イットリア安定化ジルコニア（YSZ）足場の高温製作

要約

さらに動画を探す

この動画の章

製造、ち密化、および3Dカーボンナノチューブの微細構造のレプリカ成形

Gaslessナノエネルギー物質の調製と反応性

エアロゾルデポジション法を用いて厚い高密度イットリウム鉄ガーネット膜の形成

エアロゾルによる金属酸化物の構造の化学蒸着: 酸化亜鉛棒

化学合成チタン酸バリウム多孔質セラミックス薄膜の気孔率誘起歪による強誘電相の熱安定化

マルチ材料セラミックベースのコンポーネント-添加熱可塑性 3 D 印刷 (セラム - T3DP) 白黒ジルコニア部品の製造

金属-セラミック部品の溶融フィラメント製作 (FFF)

光造形法による傾斜機能セラミック材料の添加剤の製造

バイオメディカル応用のための機械的に調整可能な生物活性金属スキャフォールドの作製

シリコン上のエピタキシャルナノ構造α-クオーツフィルム:材料から新しいデバイスへ

によってナノ構造イットリア安定化ジルコニア（YSZ）足場の高温製作

要約

さらに動画を探す

この動画の章

製造、ち密化、および3Dカーボンナノチューブの微細構造のレプリカ成形

Gaslessナノエネルギー物質の調製と反応性

エアロゾルデポジション法を用いて厚い高密度イットリウム鉄ガーネット膜の形成

エアロゾルによる金属酸化物の構造の化学蒸着: 酸化亜鉛棒

化学合成チタン酸バリウム多孔質セラミックス薄膜の気孔率誘起歪による強誘電相の熱安定化

マルチ材料セラミック ベースのコンポーネント-添加熱可塑性 3 D 印刷 (セラム - T3DP) 白黒ジルコニア部品の製造

金属-セラミック部品の溶融フィラメント製作 (FFF)

光造形法による傾斜機能セラミック材料の添加剤の製造

バイオメディカル応用のための機械的に調整可能な生物活性金属スキャフォールドの作製

シリコン上のエピタキシャルナノ構造α-クオーツフィルム:材料から新しいデバイスへ

マルチ材料セラミックベースのコンポーネント-添加熱可塑性 3 D 印刷 (セラム - T3DP) 白黒ジルコニア部品の製造