この研究は、KAIST の気候変動研究ハブによって支えられた (付与号N11160012)、大手外国研究所募集プログラム韓国国立研究財団によって資金を供給科学省、ICT および将来計画 (グラント 2011-0030065 号)、大手人材トレーニング プログラム地域の新産業を通じて、国立研究財団の韓国 (NRF) とが出資、科学省、ICT 将来計画 (付与なし。NRF-2016H1D5A1910603)。彼らのサポートは大歓迎です。

1。 材料準備 <ol><li>複合材料の調製 注: 注意、ご使用する前に関連するすべての材料安全データ用紙 (MSDS) を参照してください。いくつかのこれらのメソッドで使用される化学物質の有毒で発がん性があります。ナノ材料の一括対応と比較して追加の危険があります。工学的制御 (ヒューム フード、グローブ ボックス) と個人用保護具 (保護メガネ、手袋、白衣、フルレングス パンツ、閉じてつま先の靴) の使用を含む、実験を実行するときにすべての適切な安全対策を使用してください 。
	注: アプリケーションによっては、補強繊維の種類することができます 1 つまたは以下の組み合わせ: 一方向繊維、織物、不織布・ フェルト、切り刻まれた繊維。
	<ol><li>方向繊維型 <ol><li>を使用する最も便利な中古含浸複合材料 (プリプレグ) を使用します</li>。
			<li>は、0 ° と 90 ° の分割を避けるためを含む積層順序のプリプレグをスタックします。たとえば、スタックに [0 3 90/3] s.</li>
		</ol></li> <li>織布タイプ <ol><li>準備平織炭素繊維およびフィルム型エポキシ樹脂です。プリプレグを使用している場合手順 1.1.2.1 に 1.1.2.6</li>。
			<li>は、99.5% アセトンまたは脱脂のため他の溶剤で布を洗浄します。汚染を避けるために洗浄後、布を処理するときは注意が必要。きれいな表面または糸くずのワイプに布を配置します</li>。
			<li>10 分の周囲条件下で乾燥することによって溶媒を除去</li>
			<li>皮バックアップ エポキシ樹脂膜を切り、カーボン生地の 1 プライにフィルム型エポキシの 1 プライを添付します</li>。
			<li>は事前に 10 70 ° C まで加熱されたホット プレート上エポキシ添付カーボン生地を配置前含浸用 s.</li>
			<li>10 min. の周囲条件で準備されたプリプレグを冷却し、その他のバックアップのフィルムの剥がし</li>。
			<li>希望の積層で布をスタック; たとえば、[0] にスタック 3.</li>
		</ol></li> <li>不織感じた <ol><li>非編まれたフェルトを準備します</li>。
			<li>は、99.5% アセトンまたは他の溶剤脱脂のフェルトを浄化します。汚染を避けるためにクレンジング後フェルトを処理するときは注意が必要。きれいな表面または糸くずのワイプにフェルトを配置します</li>。
			<li>皮バックアップ エポキシ樹脂膜を切り、フィルム型エポキシ樹脂の 3 プライを両側に感じたカーボンの 1 プライにアタッチします</li>。
			<li>場所エポキシ添付炭素は 10 の 70 ° C に予熱、ホット プレートに感じた前含浸用 s.</li>
			<li>10 min. の周囲条件で準備されたプリプレグを冷却し、その他のバックアップのフィルムの剥がし</li>。
		</ol></li></ol></li> <li>ソフト層の準備 注: 柔らかな層、ポリテトラフルオロ エチレン (PTFE)、フッ化エチレン プロピレン (FEP)、あるいはポリエチレン、ポリプロピレンなどのポリオレフィンなどフッ素樹脂またはシリコーンゴム、フッ素ゴムなどの合成ゴムを使用することができます。このプロトコルでは FEP フィルムを採用し、その降伏強度滴以上大幅に 120 ° c. 25 μ m 厚 FEP は一方向繊維や不織フェルト複合材料に適した厚み 100 μ m 厚の FEP は編まれた生地のために適切複合 10 を入力します。
	<ol><li>浄化 99.5% アセトンで柔らかな層。シワやピンホールを避けるために注意して処理します</li>。
		<li>ワイプ ソフト アセトン オフ層糸くずのおしりふき。それは硬化プロセス中にコンポジットに転送されますは柔らかな層に汚染がないことを確認します。これらは合成だけでなく、圧縮金型を傷つける恐れがありますので、ほこりや小さな粒子から柔らかな層が常します</li>。
	</ol></li></ol> 2。複合加工 <ol><li>圧縮金型の取り付け <ol><li>サイズ 120 mm × 120 mm の空洞を持つ圧縮金型を準備します</li>。
		<li>は、圧縮金型に離型を適用します。単にペースト スプレー、金型の離型や金型リリースままの薄い層のみまで糸くずのおしりふきで拭いてください</li>。
		<li>準備された複合材料積層板の 118 × 118 mm のサイズにカットします</li>。
		<li>下型 FEP フィルム 25 μ m 厚の場所 1 プライします</li>。
		<li>FEP フィルム複合材料積層板を配置し、積層物の別の FEP フィルムを配置します</li>。
		<li>柔らかな層を平らにし、ソフト層と積層間捕捉された空気の泡を削除します</li>。
		<li>圧縮成形用金型を閉じます</li>。
	</ol></li> <li>圧縮成形 <ol><li>熱ホットプレス 150 ° C 
		注: 金型試験片の温度は、この状態で 140 ° C です。低温の使用もエラストマーまたはポリオレフィン系樹脂が柔らかな層を採用している場合に可能です。複合材料の硬化温度と硬化温度を決定する柔らかな層の軟化温度の両方を考慮します</li>。
		<li>ホット プレスの金型を配置します</li>。
		ホット プレスを使用して <li>適用圧力; 硬化スケジュールと圧力は、複合型に依存します。
		<ol><li>方向繊維複合材料の適用 30 分 20 MPa の定圧; 追加のプロセスは必要ありません</li>。
			<li>不織布タイプ複合の 20 MPa を適用します。4 分、8 分後でゼロに圧力を解放し、すぐに 20 MPa を再度適用します 。
			注: このプロセスは、パージと呼ばれます、その目的は、削除過剰な樹脂と内包された空気の泡。複合材料; のサイズによってパージ ステップ数を増加可能性があります。大きいサイズの複合材料は、詳細パージを必要とします。
			<ol><li>ただし、樹脂の粘度を高めるために、開始後パージしません。合計で 30 分間治療します</li>。
			</ol></li> <li>非編まれたフェルト型コンポジット、適用圧力オーバー シュートは、ボイドが発生の 30 分注意 3 MPa と最終製品の欠陥。圧力オーバー シュートを避けるためにゆっくりと圧力を高める</li>。
		</ol></li> <li>ホット プレスで圧縮金型を作製した複合材料のガラス転移温度は、120 の ° C 以下に圧力を解放せずクールします</li>。
		<li>圧力を解放し、ホットプレスから圧縮金型を削除します</li>。
		<li>圧縮金型から最終製品を脱型します</li>。
	</ol>
	</li>
</ol>

<ol>
	<li>Hwang, I. U., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bipolar+plate+made+of+carbon+fiber+epoxy+composite+for+polymer+electrolyte+membrane+fuel+cells.">Bipolar plate made of carbon fiber epoxy composite for polymer electrolyte membrane fuel cells.</a> J Power Sources. 184 (1), 90-94 (2008).</li><li>Avasarala, B., Haldar, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+surface+roughness+of+composite+bipolar+plates+on+the+contact+resistance+of+a+proton+exchange+membrane+fuel+cell.">Effect of surface roughness of composite bipolar plates on the contact resistance of a proton exchange membrane fuel cell.</a> J Power Sources. 188 (1), 225-229 (2009).</li><li>Yu, H. N., Lim, J. W., Kim, M. K., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasma+treatment+of+the+carbon+fiber+bipolar+plate+for+PEM+fuel+cell.">Plasma treatment of the carbon fiber bipolar plate for PEM fuel cell.</a> Compos Struct. 94 (5), 1911-1918 (2012).</li><li>Lim, J. W., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+composite-metal+hybrid+bipolar+plates+for+PEM+fuel+cells.">Development of composite-metal hybrid bipolar plates for PEM fuel cells.</a> Int J Hydrogen Energy. 37 (17), (2012).</li><li>Kim, B. G., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electromagnetic-carbon+surface+treatment+of+composite+bipolar+plate+for+high-efficiency+polymer+electrolyte+membrane+fuel+cells.">Electromagnetic-carbon surface treatment of composite bipolar plate for high-efficiency polymer electrolyte membrane fuel cells.</a> J Power Sources. 195 (6), 1577-1582 (2010).</li><li>Kim, B. G., Lim, J. W., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+single-type+aluminum/composite+hybrid+bipolar+plate+with+surface+modification+for+high+efficiency+PEMFC.">A single-type aluminum/composite hybrid bipolar plate with surface modification for high efficiency PEMFC.</a> Int J Hydrogen Energy. 36 (4), 3087-3095 (2011).</li><li>Yu, H. N., Lim, J. W., Suh, J. D., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+graphite-coated+carbon+fiber+epoxy+composite+bipolar+plate+for+polymer+electrolyte+membrane+fuel+cell.">A graphite-coated carbon fiber epoxy composite bipolar plate for polymer electrolyte membrane fuel cell.</a> J Power Sources. 196 (23), 9868-9875 (2011).</li><li>Kim, K. H., Kim, B. G., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+carbon+composite+bipolar+plate+(BP)+for+vanadium+redox+flow+battery+(VRFB).">Development of carbon composite bipolar plate (BP) for vanadium redox flow battery (VRFB).</a> Compos Struct. 109, 253-259 (2014).</li><li>Lee, D., Lim, J. W., Nam, S., Choi, I., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gasket-integrated+carbon/silicone+elastomer+composite+bipolar+plate+for+high-temperature+PEMFC.">Gasket-integrated carbon/silicone elastomer composite bipolar plate for high-temperature PEMFC.</a> Compos Struct. 128, 284-290 (2015).</li><li>Lee, D., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electro-mechanical+properties+of+the+carbon+fabric+composites+with+fibers+exposed+on+the+surface.">Electro-mechanical properties of the carbon fabric composites with fibers exposed on the surface.</a> Compos Struct. 140, 77-83 (2016).</li><li>Lee, D., Lim, J. W., Nam, S., Choi, I., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Method+for+exposing+carbon+fibers+on+composite+bipolar+plates.">Method for exposing carbon fibers on composite bipolar plates.</a> Compos Struct. 134, 1-9 (2015).</li><li>Lee, D., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carbon+composite+bipolar+plate+for+high-temperature+proton+exchange+membrane+fuel+cells+(HT-PEMFCs).">Carbon composite bipolar plate for high-temperature proton exchange membrane fuel cells (HT-PEMFCs).</a> J Power Sources. 327, 119-126 (2016).</li><li>Lee, D., Choe, J., Nam, S., Lim, J. W., Choi, I., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+non-woven+carbon+felt+composite+bipolar+plates+using+the+soft+layer+method.">Development of non-woven carbon felt composite bipolar plates using the soft layer method.</a> Compos struct. 160, 976-982 (2016).</li><li>Lee, D., Lim, J. W., Lee, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cathode/anode+integrated+composite+bipolar+plate+for+high-temperature+PEMFC.">Cathode/anode integrated composite bipolar plate for high-temperature PEMFC.</a> Compos Struct. 167, 144-151 (2017).</li><li>Lee, D., Oh, Y., Nam, S., Choe, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adhesion+Characteristics+of+Fiber-exposed+Glass+Composites.">Adhesion Characteristics of Fiber-exposed Glass Composites.</a> Compos Struct. 165, 9-14 (2017).</li></ol>

著者が明らかに何もありません。

ソフト層法は、製造コストと従来の方法と比較して重要な利点を提供します。3 種類ソフト層法による複合材料のすべては、電気的特性、機械的特性、ガス透過性と接着特性の面でユニークな特性を示します。
電気的特性の測定、4 点プローブ法が使用されました。ASR を 5 回測定し、そのバイポーラ プレートの代表値として平均値をとった。5 つのバイポーラ プレート?...

バイポーラ プレートは、エネルギー変換システム、燃料電池や電池などのエネルギー貯蔵システムの多機能キー コンポーネントです。バイポーラ プレートの主要な機能の要件は次のとおりです: 高圧縮圧力と外部の影響と高に耐えられるようにオーム損失、高い機械的性質を減らすために板厚方向の高い電気伝導度大量生産の生産性。
黒鉛とバイポーラ プレート用材料として採用された従来の金属と比較して、炭素繊維/エポキシ複合材料ある高い強度と剛性、システムの重量が大幅に削減できることを示す従来のバイポーラ プレート材料を複合材1に置き換えます。ただし、従来炭素繊維/エポキシ複合材料複合表面上に形成された樹脂リッチな層による大面積比抵抗 (ASR) の結果、板厚方向に電気伝導度貧しいがあります。絶縁樹脂リッチな層は導電性炭素繊維と別のバイポーラ プレート、ガス拡散層、(GDL) など、隣接するコンポーネント間の直接の接触を防ぎ、炭素電極 (CFE) を感じた。
樹脂リッチな層による高い ASR を解決する多くの研究を行った。最初のアプローチは、樹脂リッチな層を選択的に削除する表面処理方法をだった。たとえば、機械的な研磨は表面2に樹脂を削除しようとしています。ただし、炭素繊維も被害を受けた、貧しい ASR につながった。プラズマ治療3,4とマイクロ波治療方法5,6も、ファイバーの破損を避けるために開発されたが、それらは均一化と低生産性で起因しました。2 番目の方法では、導電性層塗装方法には、膨張黒鉛コーティング7,8が含まれています。このメソッドは、正常に ASR を削減、複合バイポーラ プレートを製造するための標準的な方法と見なされています。しかし、それは高価、機械的強度が低いため耐久性・剥離の問題があります。
本研究では複合バイポーラ プレート表面に炭素繊維を公開できる製法小説「軟層法」が示されていますいます。このメソッドの主な目的は、低製造コストの低い ASR を取得することです。ソフト層法は、圧縮型とバイポーラ プレート間高分子リリース フィルムなどの薄いソフト層を採用しています。圧縮型と柔らかな層のデタッチに硬化後バイポーラ製缶は炭素繊維が、後表面処理表面に露出を表示します。このメソッドだけでなく ASR を減少も大幅機械的性質の向上、ガス透過性の問題を解決しました。このメソッドは、他の多くの目的のため適用できる: 導電性プレートの薄い複合材の製造と表面処理なし共同接着剤の試作開発。

<table width="891">
	<tbody>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Unidirectional carbon/epoxy prepreg</td>
			<td class="xl63" style="width:72pt" width="96">SK Chemicals</td>
			<td class="xl63" style="width:110pt" width="146">USN020</td>
			<td class="xl66" style="width:264pt" width="352">Used to fabricate unidirectional carbon composite</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Plain weave carbon fabric/epoxy prepreg</td>
			<td class="xl63" style="width:72pt" width="96">SK Chemicals</td>
			<td class="xl63" style="width:110pt" width="146">WSN 1k</td>
			<td class="xl66">Used to fabricate fabric carbon composite</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Plain weave carbon fabric</td>
			<td class="xl63" style="width:72pt" width="96">SK Chemicals</td>
			<td class="xl63" style="width:110pt" width="146">C-112</td>
			<td class="xl66">Used to fabricate fabric carbon composite</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Non-woven carbon felt</td>
			<td class="xl63" style="width:72pt" width="96">Newell</td>
			<td class="xl63" style="width:110pt" width="146">Graphite felt 3 mm</td>
			<td class="xl66">Used to fabricated felt carbon composite</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Film type epoxy resin</td>
			<td class="xl63" style="width:72pt" width="96">SK Chemicals</td>
			<td class="xl63" style="width:110pt" width="146">K51</td>
			<td class="xl66">Used as a matrix of the composite</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Acetone 99.5%</td>
			<td class="xl63" style="width:72pt" width="96">Samchun</td>
			<td class="xl63" style="width:110pt" width="146">67-64-1</td>
			<td class="xl66">Used to cleanse the carbon fiber and the soft layers</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Mold release</td>
			<td class="xl63" style="width:72pt" width="96">ShinEtsu</td>
			<td class="xl63" style="width:110pt" width="146">KF-96</td>
			<td class="xl66">Used to coat the mold</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Release film</td>
			<td class="xl63" style="width:72pt" width="96">Airtech</td>
			<td class="xl63" style="width:110pt" width="146">A4000V</td>
			<td class="xl66">Used as a soft layer</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Compression mold</td>
			<td class="xl63" style="width:72pt" width="96">N/A</td>
			<td class="xl63" style="width:110pt" width="146">N/A</td>
			<td class="xl66">Machined in lab. Material: NAK80</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Hot press</td>
			<td class="xl63" style="width:72pt" width="96">Hydrotek 100</td>
			<td class="xl63" style="width:110pt" width="146">N/A</td>
			<td class="xl66">Used to apply pressure and heat</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl63" height="21" style="width:223pt;height:15.75pt" width="297">Scanning electron microscope</td>
			<td class="xl63" style="width:72pt" width="96">FEI Compnay</td>
			<td class="xl63" style="width:110pt" width="146">Magellan 400</td>
			<td class="xl66">Used to investigate the surface of the composite</td>
		</tr>
	</tbody>
</table>

experimental implementation of a new composite fabrication method: exposing bare fibers on the composite surface by the soft layer method

バイポーラ プレートは、プロトン交換膜燃料電池 (固体) とバナジウム レドックス フロー電池 (VRFBs) の重要なコンポーネントです。高い電気伝導度、高い機械的性質、高い生産性多機能コンポーネントです。
この点で、炭素繊維/エポキシ樹脂複合材料は多くの固有のもろさのためシステム全体の壊滅的な障害につながる従来の黒鉛セパレーターを交換する理想的な材料をすることができます。炭素繊維/エポキシ複合材料は、高い機械的性質を持って、製造が容易な板厚方向の電気伝導度は樹脂リッチな層がその表面に形成するため貧しいです。したがって、膨張黒鉛コーティングは、導電性の問題を解決するために採択されました。しかし、膨張黒鉛コーティングだけでなく製造コストの増加、貧困層の力学的性質があります。
本研究では複合表面の繊維を公開するメソッドが示されています。複合材料の加工後の表面処理による繊維を公開することができます現在多くの方法があります。ただし、この新しい方法は表面処理を不要繊維、複合材料の製造時に公開されているためです。表面にカーボン ファイバーを公開すると、電気伝導度と複合材料の機械的強度を大幅に増加します。

作製した標本は、走査型電子顕微鏡 (SEM) (図 1) を使用して観察されます。繊維の上をカバーする樹脂リッチな層がわずか数ミクロンの厚さには、供試体の上部に観察光学顕微鏡像は適していません。5 ° で試料を傾斜による SEM 画像は代表的な画像を提供します。樹脂で覆われた表面には、従来の圧縮成形により作製した複合材料と比較して、複...

Watch this Scientific Journal Video about Experimental Implementation of a New Composite Fabrication Method: Exposing Bare Fibers on the Composite Surface by the Soft Layer Method at JoVE.com

Experimental Implementation of a New Composite Fabrication Method: Exposing Bare Fibers on the Composite Surface by the Soft Layer Method

ガレージの豊富な領域を排除することによって複合表面にファイバーを公開するためのプロトコルが表示されます。繊維がポストの表面処理ではなく、複合体の製造中にさらされています。公開される炭素複合材料は、板厚方向と高い機械的性質で高い電気伝導度を表わします。

新しい複合加工法の試作: 軟層法による複合表面にファイバーを公開

The bipolar plate is a key component in proton exchange membrane fuel cells (PEMFCs) and vanadium redox flow batteries (VRFBs). It is a multi-functional ...

experimental-implementation-new-composite-fabrication-method-exposing

Universidad de Cartagena UDEC

Research

JoVE Journal

Engineering

8.2K ビュー.  Korea Advanced Institute of Science and Technology. ガレージの豊富な領域を排除することによって複合表面にファイバーを公開するためのプロトコルが表示されます。繊維がポストの表面処理ではなく、複合体の製造中にさらされています。公開される炭素複合材料は、板厚方向と高い機械的性質で高い電気伝導度を表わします。

ビデオ: Experimental Implementation of a New Composite Fabrication Method: Exposing Bare Fibers on the Composite Surface by the Soft Layer Method

Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed polymer optical fiber is composed of 80,000 strands of poly (methyl methacrylate) (PMMA) and polystyrene (PS) that are randomly mixed and drawn into a square cross section optical fiber with a side width of 250 &mu;m. Initially, each strand is 200 &mu;m in diameter and 8-inches long. During the mixing process of the original fiber strands, the fibers cross over each other; however, a large draw ratio guarantees that the refractive index profile is invariant along the length of the fiber for several tens of centimeters. The large refractive index difference of 0.1 between the disordered sites results in a small localized beam radius that is comparable to the beam radius of conventional optical fibers. The input light is launched from a standard single mode optical fiber using the butt-coupling method and the near-field output beam from the disordered fiber is imaged using a 40X objective and a CCD camera. The output beam diameter agrees well with the expected results from the numerical simulations. The disordered optical fiber presented in this work is the first device-level implementation of 2D Anderson localization, and can potentially be used for image transport and short-haul optical communication systems.

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. This microstructured fiber can transport a small localized beam with a radius that is comparable to the beam radius of conventional optical fibers.

ライトの横アンダーソン局在のために無秩序ポリマー光ファイバの作製と評価

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed ...

工学

Fabrication of Uniform Nanoscale Cavities via Silicon Direct Wafer Bonding

Measurements of the heat capacity and superfluid fraction of confined 4He have been performed near the lambda transition using lithographically patterned and bonded silicon wafers. Unlike confinements in porous materials often used for these types of experiments3, bonded wafers provide predesigned uniform spaces for confinement. The geometry of each cell is well known, which removes a large source of ambiguity in the interpretation of data.
Exceptionally flat, 5 cm diameter, 375 &#181;m thick Si wafers with about 1 &#181;m variation over the entire wafer can be obtained commercially (from Semiconductor Processing Company, for example). Thermal oxide is grown on the wafers to define the confinement dimension in the z-direction. A pattern is then etched in the oxide using lithographic techniques so as to create a desired enclosure upon bonding. A hole is drilled in one of the wafers (the top) to allow for the introduction of the liquid to be measured. The wafers are cleaned2 in RCA solutions and then put in a microclean chamber where they are rinsed with deionized water4. The wafers are bonded at RT and then annealed at ~1,100 &#176;C. This forms a strong and permanent bond. This process can be used to make uniform enclosures for measuring thermal and hydrodynamic properties of confined liquids from the nanometer to the micrometer scale.

A method for permanently bonding two silicon wafers so as to realize a uniform enclosure is described. This includes wafer preparation, cleaning, RT bonding, and annealing processes. The resulting bonded wafers (cells) have uniformity of enclosure ~1%1,2. The resulting geometry allows for measurements of confined liquids and gasses.

シリコン直接ウェハー接合による均一ナノスケールキャビティの作製

Measurements of the heat capacity and superfluid fraction of confined 4He have been performed near the lambda transition using lithographically patterned ...

A Fabrication Method for Highly Stretchable Conductors with Silver Nanowires

Stretchable electronics are identified as a key technology for electronic applications in the next generation. One of the challenges in fabrication of stretchable electronic devices is the preparation of stretchable conductors with great mechanical stability. In this study, we developed a simple fabrication method to chemically solder the contact points between silver nanowire (AgNW) networks. AgNW nanomesh was first deposited on a glass slide via spray coating method. A reactive ink composed of silver nanoparticle (AgNPs) precursors was applied over the spray coated AgNW thin films. After heating for 40 min, AgNPs were preferentially generated over the nanowire junctions to solder the AgNW nanomesh, and reinforced the conducting network. The chemically modified AgNW thin film was then transferred to polyurethane (PU) substrates by casting method. The soldered AgNW thin films on PU exhibited no obvious change in electrical conductivity under stretching or rolling process with elongation strains up to 120%.

A simple synthesis method is used to chemically solder silver nanowire thin film to fabricate highly stretchable and conductive metal conductors.

シルバーナノワイヤーと伸縮性の高い導体の製造方法

Stretchable electronics are identified as a key technology for electronic applications in the next generation. One of the challenges in fabrication of ...

Emission Spectroscopic Boundary Layer Investigation during Ablative Material Testing in Plasmatron

Ablative Thermal Protection Systems (TPS) allowed the first humans to safely return to Earth from the moon and are still considered as the only solution for future high-speed reentry missions. But despite the advancements made since Apollo, heat flux prediction remains an imperfect science and engineers resort to safety factors to determine the TPS thickness. This goes at the expense of embarked payload, hampering, for example, sample return missions. 
Ground testing in plasma wind-tunnels is currently the only affordable possibility for both material qualification and validation of material response codes. The subsonic 1.2MW Inductively Coupled Plasmatron facility at the von Karman Institute for Fluid Dynamics is able to reproduce a wide range of reentry environments. This protocol describes a procedure for the study of the gas/surface interaction on ablative materials in high enthalpy flows and presents sample results of a non-pyrolyzing, ablating carbon fiber precursor. With this publication, the authors envisage the definition of a standard procedure, facilitating comparison with other laboratories and contributing to ongoing efforts to improve heat shield reliability and reduce design uncertainties.
The described core techniques are non-intrusive methods to track the material recession with a high-speed camera along with the chemistry in the reactive boundary layer, probed by emission spectroscopy. Although optical emission spectroscopy is limited to line-of-sight measurements and is further constrained to electronically excited atoms and molecules, its simplicity and broad applicability still make it the technique of choice for analysis of the reactive boundary layer. Recession of the ablating sample further requires that the distance of the measurement location with respect to the surface is known at all times during the experiment. Calibration of the optical system of the applied three spectrometers allowed quantitative comparison. At the fiber scale, results from a post-test microscopy analysis are presented.

Development of new ablative materials and their numerical modeling requires extensive experimental investigation. This protocol describes procedures for material response characterization in plasma flows with the core techniques being non-intrusive methods to track the material recession along with the chemistry in the reactive boundary layer by emission spectroscopy.

プラズマトロン内のアブレーション材料試験中の放射分光境界層調査

Ablative Thermal Protection Systems (TPS) allowed the first humans to safely return to Earth from the moon and are still considered as the only solution ...

Testing of Nanoparticle Release from a Composite Containing Nanomaterial Using a Chamber System

With the rapid development of nanotechnology as one of the most important technologies in the 21st century, interest in the safety of consumer products containing nanomaterials is also increasing. Evaluating the nanomaterial release from products containing nanomaterials is a crucial step in assessing the safety of these products, and has resulted in several international efforts to develop consistent and reliable technologies for standardizing the evaluation of nanomaterial release. In this study, the release of nanomaterials from products containing nanomaterials is evaluated using a chamber system that includes a condensation particle counter, optical particle counter, and sampling ports to collect filter samples for electron microscopy analysis. The proposed chamber system is tested using an abrasor and disc-type nanocomposite material specimens to determine whether the nanomaterial release is repeatable and consistent within an acceptable range. The test results indicate that the total number of particles in each test is within 20% from the average after several trials. The release trends are similar and they show very good repeatability. Therefore, the proposed chamber system can be effectively used for nanomaterial release testing of products containing nanomaterials.

Nanoparticle release is tested using a chamber system that includes a condensation particle counter, an optical particle counter and sampling ports to collect filter samples for microscopy analysis. The proposed chamber system can be effectively used for nanomaterial release testing with a repeatable and consistent data range.

商工会議システムを用いたナノ材料を含む複合からのナノ粒子のリリースのテスト

With the rapid development of nanotechnology as one of the most important technologies in the 21st century, interest in the safety of consumer products ...

Strain Sensing Based on Multiscale Composite Materials Reinforced with Graphene Nanoplatelets

The electrical response of NH2-functionalized graphene nanoplatelets composite materials under strain was studied. Two different manufacturing methods are proposed to create the electrical network in this work: (a) the incorporation of the nanoplatelets into the epoxy matrix and (b) the coating of the glass fabric with a sizing filled with the same nanoplatelets. Both types of multiscale composite materials, with an in-plane electrical conductivity of ~10-3 S/m, showed an exponential growth of the electrical resistance as the strain increases due to distancing between adjacent functionalized graphene nanoplatelets and contact loss between overlying ones. The sensitivity of the materials analyzed during this research, using the described procedures, has been shown to be higher than commercially available strain gauges. The proposed procedures for self-sensing of the structural composite material would facilitate the structural health monitoring of components in difficult to access emplacements such as offshore wind power farms. Although the sensitivity of the multiscale composite materials was considerably higher than the sensitivity of metallic foils used as strain gauges, the value reached with NH2 functionalized graphene nanoplatelets coated fabrics was nearly an order of magnitude superior. This result elucidated their potential to be used as smart fabrics to monitor human movements such as bending of fingers or knees. By using the proposed method, the smart fabric could immediately detect the bending and recover instantly. This fact permits precise monitoring of the time of bending as well as the degree of bending.

The integration of conductive nanoparticles, such as graphene nanoplatelets, into glass fiber composite materials creates an intrinsic electrical network susceptible to strain. Here, different methods to obtain strain sensors based on the addition of graphene nanoplatelets into the epoxy matrix or as a coating on glass fabrics are proposed.

グラフェンナノプレートレットとマルチスケール複合材料強化に基づくひずみセンシング

The electrical response of NH2-functionalized graphene nanoplatelets composite materials under strain was studied. Two different manufacturing methods are ...

Flow-assisted Dielectrophoresis: A Low Cost Method for the Fabrication of High Performance Solution-processable Nanowire Devices

Flow-assisted dielectrophoresis (DEP) is an efficient self-assembly method for the controllable and reproducible positioning, alignment, and selection of nanowires. DEP is used for nanowire analysis, characterization, and for solution-based fabrication of semiconducting devices. The method works by applying an alternating electric field between metallic electrodes. The nanowire formulation is then dropped onto the electrodes which are on an inclined surface to create a flow of the formulation using gravity. The nanowires then align along the gradient of the electric field and in the direction of the liquid flow. The frequency of the field can be adjusted to select nanowires with superior conductivity and lower trap density. 
In this work, flow-assisted DEP is used to create nanowire field effect transistors. Flow-assisted DEP has several advantages: it allows selection of nanowire electrical properties; control of nanowire length; placement of nanowires in specific areas; control of orientation of nanowires; and control of nanowire density in the device. 
The technique can be expanded to many other applications such as gas sensors and microwave switches. The technique is efficient, quick, reproducible, and it uses a minimal amount of dilute solution making it ideal for the testing of novel nanomaterials. Wafer scale assembly of nanowire devices can also be achieved using this technique, allowing large numbers of samples for testing and large-area electronic applications.

In this paper, flow assisted dielectrophoresis is demonstrated for the self-assembly of nanowire devices. The fabrication of a silicon nanowire field effect transistor is shown as an example.

誘電泳動の流れ支援: 高性能低温硬化型ナノワイヤ デバイス作製のための低コストの方法

Flow-assisted dielectrophoresis (DEP) is an efficient self-assembly method for the controllable and reproducible positioning, alignment, and selection of ...

A Fabrication and Measurement Method for a Flexible Ferroelectric Element Based on Van Der Waals Heteroepitaxy

Flexible non-volatile memories have received much attention as they are applicable for portable smart electronic device in the future, relying on high-density data storage and low-power consumption capabilities. However, the high-quality oxide based nonvolatile memory on flexible substrates is often constrained by the material characteristics and the inevitable high-temperature fabrication process. In this paper, a protocol is proposed to directly grow an epitaxial yet flexible lead zirconium titanate memory element on muscovite mica. The versatile deposition technique and measurement method enable the fabrication of flexible yet single-crystalline non-volatile memory elements necessary for the next generation of smart devices.

In this paper, we present a protocol to directly grow an epitaxial yet flexible lead zirconium titanate memory element on muscovite mica.

作製と Van Der waals 力ヘテロエピタキシーに基づくフレキシブル強誘電性要素の測定法

Flexible non-volatile memories have received much attention as they are applicable for portable smart electronic device in the future, relying on ...

Magnet Assisted Composite Manufacturing: A Flexible New Technique for Achieving High Consolidation Pressure in Vacuum Bag/Lay-Up Processes

This work demonstrates a protocol to improve the quality of composite laminates fabricated by wet lay-up vacuum bag processes using the recently developed magnet assisted composite manufacturing (MACM) technique. In this technique, permanent magnets are utilized to apply a sufficiently high consolidation pressure during the curing stage. To enhance the intensity of the magnetic field, and thus, to increase the magnetic compaction pressure, the magnets are placed on a magnetic top plate. First, the entire procedure of preparing the composite lay-up on a magnetic bottom steel plate using the conventional wet lay-up vacuum bag process is described. Second, placement of a set of Neodymium-Iron-Boron permanent magnets, arranged in alternating polarity, on the vacuum bag is illustrated. Next, the experimental procedures to measure the magnetic compaction pressure and volume fractions of the composite constituents are presented. Finally, methods used to characterize microstructure and mechanical properties of composite laminates are discussed in detail. The results prove the effectiveness of the MACM method in improving the quality of wet lay-up vacuum bag laminates. This method does not require large capital investment for tooling or equipment and can also be used to consolidate geometrically complex composite parts by placing the magnets on a matching top mold positioned on the vacuum bag.

A new technique for applying consolidation pressure on the vacuum bag lay-up to fabricate composite laminates is described. The goal of this protocol is to develop a simple, cost-effective technique to improve the quality of laminates fabricated by the wet lay-up vacuum bag method.

磁石は、複合材生産を支援: 柔軟な新しい技術高圧真空袋/Lay アップ プロセスを達成するため

This work demonstrates a protocol to improve the quality of composite laminates fabricated by wet lay-up vacuum bag processes using the recently developed ...

Cutting Procedures, Tensile Testing, and Ageing of Flexible Unidirectional Composite Laminates

Many body armor designs incorporate unidirectional (UD) laminates. UD laminates are constructed of thin (&#60;0.05 mm) layers of high-performance yarns, where the yarns in each layer are oriented parallel to each other and held in place using binder resins and thin polymer films. The armor is constructed by stacking the unidirectional layers in different orientations. To date, only very preliminary work has been performed to characterize the ageing of the binder resins used in unidirectional laminates and the effects on their performance. For example, during the development of the conditioning protocol used in the National Institute of Justice Standard-0101.06, UD laminates showed visual signs of delamination and reductions in V50, which is the velocity at which half of the projectiles are expected to perforate the armor, after ageing. A better understanding of the material property changes in UD laminates is necessary to comprehend the long-term performance of armors constructed from these materials. There are no current standards recommended for mechanically interrogating unidirectional (UD) laminate materials. This study explores methods and best practices for accurately testing the mechanical properties of these materials and proposes a new test methodology for these materials. Best practices for ageing these materials are also described.

The goal of the study was to develop protocols to prepare consistent specimens for accurate mechanical testing of high-strength aramid or ultra-high-molar-mass polyethylene-based flexible unidirectional composite laminate materials and to describe protocols for performing artificial ageing on these materials.

柔軟な単方向複合ラミネートの切断手順、引張試験、およびエージング

Many body armor designs incorporate unidirectional (UD) laminates. UD laminates are constructed of thin (&#60;0.05 mm) layers of high-performance yarns, ...

新しい複合加工法の試作: 軟層法による複合表面にファイバーを公開

要約

さらに動画を探す

この動画の章

ライトの横アンダーソン局在のために無秩序ポリマー光ファイバの作製と評価

シリコン直接ウェハー接合による均一ナノスケールキャビティの作製

シルバーナノワイヤーと伸縮性の高い導体の製造方法

プラズマトロン内のアブレーション材料試験中の放射分光境界層調査

商工会議システムを用いたナノ材料を含む複合からのナノ粒子のリリースのテスト

グラフェンナノプレートレットとマルチスケール複合材料強化に基づくひずみセンシング

誘電泳動の流れ支援: 高性能低温硬化型ナノワイヤデバイス作製のための低コストの方法

作製と Van Der waals 力ヘテロエピタキシーに基づくフレキシブル強誘電性要素の測定法

磁石は、複合材生産を支援: 柔軟な新しい技術高圧真空袋/Lay アッププロセスを達成するため

柔軟な単方向複合ラミネートの切断手順、引張試験、およびエージング

新しい複合加工法の試作: 軟層法による複合表面にファイバーを公開

要約

さらに動画を探す

この動画の章

ライトの横アンダーソン局在のために無秩序ポリマー光ファイバの作製と評価

シリコン直接ウェハー接合による均一ナノスケールキャビティの作製

シルバーナノワイヤーと伸縮性の高い導体の製造方法

プラズマトロン内のアブレーション材料試験中の放射分光境界層調査

商工会議システムを用いたナノ材料を含む複合からのナノ粒子のリリースのテスト

グラフェンナノプレートレットとマルチスケール複合材料強化に基づくひずみセンシング

誘電泳動の流れ支援: 高性能低温硬化型ナノワイヤ デバイス作製のための低コストの方法

作製と Van Der waals 力ヘテロエピタキシーに基づくフレキシブル強誘電性要素の測定法

磁石は、複合材生産を支援: 柔軟な新しい技術高圧真空袋/Lay アップ プロセスを達成するため

柔軟な単方向複合ラミネートの切断手順、引張試験、およびエージング

誘電泳動の流れ支援: 高性能低温硬化型ナノワイヤデバイス作製のための低コストの方法

磁石は、複合材生産を支援: 柔軟な新しい技術高圧真空袋/Lay アッププロセスを達成するため