Name: indirect fabrication of lattice metals with thin sections using centrifugal casting
Uploaded: 2016-05-14T14:00:00.000+00:00
Duration: 8 min 32 s
Description: Watch this Scientific Journal Video about Indirect Fabrication of Lattice Metals with Thin Sections Using Centrifugal Casting at JoVE.com

Este estudo recebeu apoio da pesquisa de iniciação Grant (RIG) do Vice-Presidente de Pesquisa e Desenvolvimento Económico da Universidade do Norte do Texas (UNT). Os autores também agradecem KCIS Co. Ltd para suportar parcialmente este estudo. O apoio da PACCAR Instituto de Tecnologia da UNT para o sucesso desta publicação é muito apreciada.

1. Planejamento de Experimento <ol><li> Desenhar um padrão de sacrifício (uma estrutura de treliça octeto com um sistema de sprue), utilizando software computer aided design (CAD) como mostrado na Figura 1 e salvar o modelo CAD como um formato de arquivo STL. Nota: O padrão de sacrifício é um padrão integrado da estrutura de armação octeto com um sistema de canal de entrada que serão, eventualmente, derretida para a fundição. Uma vez que o padrão sacrificial inclui tanto a estrutura de armação octeto e o sistema de canal de entrada, não representar exactamente o próprio fardo do octeto. Um arquivo STL do padrão de sacrifício é fornecido. Registe o volume do padrão sacrificial fornecida pelo software de CAD, que será utilizado para calcular a massa «metais. </li><li> Abra o desenho CAD do padrão sacrificial sobre o software de impressão 3D conectado a uma impressora 3D para imprimir o padrão. </li><li> Certifique-se de que a impressora 3D tem UV plástico suficiente curável / refratário acrílico e um material de suporte feito de uma ceranos cartuchos de impressora. </li></ol> 2. Fabricação de Padrão sacrificial <ol><li> Fabrico do padrão de sacrifício que consiste na estrutura de treliça octeto e o sistema de canal de entrada usando uma impressora 3D (Figura 2A - C). Nota: Processos em 2.1.3 - 2.1.7 não são necessárias se uma impressora 3D que não gera materiais de apoio é usado. <ol><li> Enviar um arquivo STL do padrão de sacrifício para a impressora 3D para imprimir um padrão de sacrifício (Figura 2A). </li><li> Derreter a um material de suporte do padrão de sacrifício num forno a acima da temperatura de fusão do material de suporte (60 - 70 C) durante 2 horas (Figura 2B). Nota: A temperatura para remover o material de suporte não deve ser demasiado elevada. Caso contrário, pode causar danos ao padrão de sacrifício. O padrão de sacrifício começa a ficar danificado em torno de 80 C neste estudo. Nota: A temperatura de fusão de suppormateriais t varia de acordo com as impressoras 3D que podem ser utilizados diferentes materiais de apoio. </li><li> Preencha um limpador ultra-sônico digital com o bebê de óleo até 2,5 L, o volume máximo que o limpador pode conter (Figura 2C). Nota: Foi recomendada pelo fornecedor da impressora 3D para usar óleo de bebê para dissolver resíduo do material de suporte do tipo cera. </li><li> Coloque o padrão de sacrifício para o limpador ultra-sônico digital e ligar a alimentação do aspirador (Figura 2C). Certifique-se de que o padrão de sacrifício é inteiramente submerso no óleo. </li><li> Remover os resíduos do material de suporte por meio de imersão do padrão de sacrifício dentro do óleo a 65 ° C durante 40 minutos (Figura 2C). </li><li> Retire o padrão de sacrifício do aspirador se o material de suporte é completamente removido. </li><li> Ter o sacrifício padrão seco com um ventilador à temperatura ambiente (~ 20 ° C) (Figura 2C). Nota: Demora cerca de 2 horasaté que o óleo sobre a superfície do padrão de sacrifício está completamente seco. Considere o padrão de sacrifício para ser totalmente secos, se a superfície não é pegajoso. </li></ol></li></ol> 3. Fabricação de Mold <ol><li> Assembléia Pattern <ol><li> Anexar uma junta de vedação de borracha para o padrão de sacrifício (o octeto do fardo com o sistema de jito) e colocá-los no fundo de um frasco em forma de cilindro com uma altura de 6,35 cm e um diâmetro de 6,35 cm (Figura 2D). Nota: Prepare dois frascos para a fundição de cada metal; Al e Cu ligas. </li><li> Verifique a junta de borracha com o padrão de sacrifício está completamente fixada no fundo do frasco. </li><li> Envolver o balão com uma fita adesiva para que mistura investimento pó-água, cujo procedimento será descrito na próxima seção, não pode vazar do frasco. </li></ol></li><li> Preparação de Mold Investimento <ol><li> Prepare pó de investimento (CaSO4 </sUB&gt;, ρ = 1019 kg / m 3) de 89 g, o qual é 87.16 ml. Use uma balança para pesagem do pó de investimento. Nota: As propriedades físicas do pó de investimento são mostrados na Tabela 1. </li><li> Despeje o pó de investimento em uma tigela (1 L). </li><li> Despeje a água (114 ml) para a tigela. Use um copo para medir o volume de água. </li><li> Misturar o pó com água investimento na tigela durante 3 min. Misture bem até que não há nódulos na mistura investimento pó-água. Caso contrário, pode causar má qualidade da superfície do molde de investimento. Seguir o fluxo de trabalho, como se mostra na Figura 3. </li><li> A fim de remover as bolhas de ar na mistura, colocar a taça numa câmara de vácuo durante 90 segundos até que as bolhas de ar não pode ser visto na mistura com o olho nu (Figura 3). </li><li> Verter a mistura em um frasco de incorporar o padrão de sacrifício e a junta de borracha (Figura 2E). </li><li> Coloque os flasK na câmara de vácuo de novo durante 90 segundos para remover o resíduo de bolhas de ar dentro da mistura (Figura 3). </li><li> Seca-se a mistura no interior do recipiente até que é endurecida a temperatura ambiente (Figura 3). Nota: Normalmente, leva cerca de 10 - 15 minutos para a mistura para ser endurecido à temperatura ambiente. </li><li> Retirar o frasco e a junta de borracha na parte inferior da mistura no frasco uma vez que a mistura é endurecida (Figura 3). Este produto pode ser chamado de um molde de gesso. </li></ol></li><li> Esgotamento <ol><li> Defina-se um tempo de queima-se no forno ao seguir o aquecimento e arrefecimento cronograma (Figura 4) de aquecimento 23-150 ° C a 2,1 C / min; 150-370 C em 3,7 C / min; 370-480 C a 1,85 C / min; 480-730 C a 4,17 C / min; 730 C durante 1 hora; arrefecimento 730-480 C na -4,17 C / min. Nota: O tempo de burn-out vars com um tamanho de frasco. Neste estudo, definir o tempo de burn-out a 6 horas. </li><li> Coloque o molde de gesso em um forno (Figura 2F). </li><li> Ligue o forno e aumentar a temperatura no forno para remover o padrão de sacrifício dentro do molde de gesso. Siga a condição de temperatura na Figura 4. Nota: Porque a UV curável / plástico acrílico moldável, o material do padrão de sacrifício, é um plástico termoendurecível acrílico-polímero, que não flua, mas é dissociado para uma fase gasosa no forno. </li></ol></li><li> Fundição (Figura 2G) <ol><li> Verifique se o braço da máquina de fundição centrífuga gira com uma velocidade angular de 425 rpm usando um tacômetro depois de ligar o poder de uma máquina de fundição centrífuga. </li><li> Prepare dois cadinhos de cerâmica que podem conter uma liga de 150 g para derreter. Use cadinhos separadas para ligas de Al e Cu para mantê-los de ser contaminado com each outra. </li><li> Ligue a alimentação da máquina de fundição centrífuga. </li><li> Usando um cortador de metal, pique as ligas em pedaços com 10 - 20 mm de comprimento. Prepara-o suficiente para preencher completamente a cavidade do molde cujo volume deve ser o mesmo que o padrão de sacrifício. Nota: A massa de metais necessários para preencher o mesmo volume da cavidade do molde varia considerando densidade variável para cada metal. </li><li> Usar panos de retardadores de combustão e luvas e óculos de proteção. Preparar um balde de água (30 L) à TA. </li><li> Tome o molde de gesso temporariamente fora do forno na Seção 3.3, instale-o no berço balão e equilibrar o braço da máquina de fundição centrífuga (Figura 5). </li><li> Coloque o molde de gesso de volta para o forno e pré-aquecer a 482 ° C antes do vazamento. </li><li> Colocar o cadinho no suporte cadinho (Figura 5). </li><li> Coloque a liga picada no cadinho. </li><li> Abrir a válvula de um átomo de oxigéniotanque conectado com um maçarico de oxigénio-acetileno e manter um nível de pressão no tanque de 96,5 kPa (14 psi). </li><li> Inflamar a chama de oxigénio-acetileno com um isqueiro e controlar a intensidade da chama, ajustando a mistura de gases. Nota: É necessário ter cuidado ao usar a tocha de oxigênio e acetileno. A sua temperatura máxima de o maçarico é de cerca de 1200 ° C. </li><li> Derreta liga picada (liga de Al ou Cu) com a tocha no cadinho até a liga completamente se torna líquido. </li><li> Agita-se a liga no cadinho com uma vara de carbono até que a liga de picada é completamente derretido. </li><li> Coloque o molde de gesso no berço balão de volta ao lado do cadinho contendo liga fundida (Figura 5). </li><li> Feche a tampa da máquina de fundição centrífuga, deixe a rotação do braço centrífuga e esperar pelo menos por 3 min. Nota: A máquina de vazamento centrífugo começa a operar assim que a tampa da máquina de moldagem é fechada. O braço centrífugaroda a uma velocidade de 425 rpm, o que corresponde à velocidade de entrada na cavidade do molde do padrão de sacrifício, v r = 8,03 m / seg 28, 29 na Figura 5, onde a ligação de entrada e a velocidade é calculada utilizando a dinâmica de partículas macroscópicas de um angular velocidade da fundição centrífuga braço 28, 29. </li><li> Desligue a energia da máquina de fundição centrífuga após a 3 min rotação do braço. </li><li> Abra a tampa da máquina de fundição. </li><li> Tome o molde de gesso fora do berço frasco com uma pinça. </li><li> Manter o molde à temperatura ambiente durante 15 - 20 min até que a cor da liga fundida transforma a sua original na fase sólida. </li><li> Usando pinças, extinguir o molde de gesso em água colocados num balde (30 L) à temperatura ambiente durante cerca de 5 min. Certifique-se de que a temperatura do molde de gesso é perto de RT após têmpera. </li><li> A fim de obter a estrutura do metal no interior do molde, dissolve-se omolde em água. O molde de gesso dissolve facilmente na água. </li></ol></li></ol> 4. Pós-Processamento de Produtos Finais de octeto Truss Metals <ol><li> Ligue a alimentação de um sandblaster. </li><li> Colocar os metais octeto do fardo sobre a plataforma no interior do jacto de areia e fechar a porta da máquina. </li><li> Coloque luvas e pegar a pistola sandblaster. </li><li> Pegue a parte do canal de entrada do produto de metal e soprar o gesso residual da estrutura do metal com o sandblaster durante 2 h. Nota: A intensidade do jacto de areia é fixado automaticamente a cerca de 550 kPa. Uma vez que o jacto de areia é operado, em seguida, o ar sai automaticamente a partir da pistola. </li><li> Mantenha o sandblaster a funcionar até o resíduo de gesso de investimento dentro do metal octeto treliça é completamente removido durante a verificação a olho nu. Nota: Não existe um critério microscópica sobre a remoção de resíduos de gesso. Isso está além do escopo deste estudo. Tele remoção do resíduo de gesso é facilmente determinada a olho nu. Uma vez que a treliça octeto é uma estrutura de células abertas, é possível ver através e verificar se ou não o resíduo de gesso é completamente removido. Nota: É necessário ter cuidado para o jacto de areia para não danificar o metal octeto armação com uma espessura de parede fina (0,5 mm) do lado de alta pressão (550 kPa). </li><li> Se o resíduo gesso investimento dentro do metal octeto treliça não é totalmente removida com o jacto de areia, usar métodos de processamento pós adicionais, por exemplo, uma limpeza ultra-sónica ou deixando o produto em água durante um dia. </li><li> No caso de utilizar um limpador ultra-sônico, preencha 0,7 L de água para o limpador ultra-sônico e coloque o metal octeto de treliça com resíduos de gesso na limpador ultra-sônico. <ol><li> Ligue a alimentação do limpador ultra-sônico. </li><li> Definir uma condição de operação, por exemplo, 3 horas a 70 ° C. </li><li> Leve o metal octeto treliça fora do limpador ultra-sônico, uma vez the operação termina. </li><li> Seca-se o metal octeto treliça à TA até que a água na superfície do metal é removida completamente. </li></ol></li><li> Como um método de pós-processamento alternativo, deixe o metal octeto de treliça em água. Isto faz com que o resíduo de gesso para ser dissolvido em água. <ol><li> Coloque o metal octeto de treliça com o resíduo de gesso na água e deixá-lo por um dia para que a força de ligação entre o gesso de investimento e a superfície do metal torna-se enfraquecer na água. </li><li> Leve o metal octeto treliça fora da água. </li><li> Seca-se o metal octeto treliça à TA até que a água na superfície do metal é removida completamente. </li></ol></li><li> Usando uma serra ou outras ferramentas adequadas, cortar o metal preenchido a cavidade da parte de sistema de jito para fora do produto metálico e obter o metal último octeto de treliça com um tamanho de 25 mm x 25 mm x 25 mm, conforme mostrado na Figura 1B. </li></ol>

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Process. 17, 28-40 (2015).</li><li>Challapalli, A., Ju, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Continuum+Model+for+Effective+Properties+of+Orthotropic+Octet-Truss+Lattice+Materials.">Continuum Model for Effective Properties of Orthotropic Octet-Truss Lattice Materials.</a> Proceedings of the ASME International Mechanical Engineering Congress and Exposition. , (2014).</li><li>Taylor, H. F., Flemings, M. C., Wulff, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Foundry Engineering. , (1959).</li><li>Mun, J., Ju, J., Thurman, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Indirect+Additive+Manufacturing+Based+Casting+(I+AM+Casting)+of+a+Lattice+Structure.">Indirect Additive Manufacturing Based Casting (I AM Casting) of a Lattice Structure.</a> Proceedings of the ASME International Mechanical Engineering Congress and Exposition. , (2014).</li><li>Mun, J., Ju, J., Thurman, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Indirect+Additive+Manufacturing+of+a+Copper+Alloy+Cubic+Lattice+Structure.">Indirect Additive Manufacturing of a Copper Alloy Cubic Lattice Structure.</a> Proceedings of the 25th Annual International Solid Freeform Fabrication Symposium. , (2014).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Volume+2+Properties+and+Selection:+Nonferrous+Alloys+and+Pure+Metals.">Volume 2 Properties and Selection: Nonferrous Alloys and Pure Metals.</a> Metals Handbook Ninth Edition. , (1979).</li><li>Romano, J., Ladani, L., Razmi, J., Sadowski, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temperature+Distribution+and+Melt+Geometry+in+Laser+and+Electron-beam+Melting+Processes+-+A+Comparison+Among+Common+Materials.">Temperature Distribution and Melt Geometry in Laser and Electron-beam Melting Processes - A Comparison Among Common Materials.</a> J. of Additive Manuf. 8, 1-11 (2015).</li></ol>

The authors have nothing to disclose.

Para fundição de metal convencional, é importante para manter o fluxo do metal fundido liso e racionalizado em &#39;laminar&#39; na cavidade do molde e prefere evitar fluxo irregular e agitado geralmente observado no fluxo turbulento 27. Por conseguinte, é importante desenhar adequadamente o sistema de entrada do canal de entrada associada com a velocidade de rotação de um braço centrífuga para manter o fluxo de metal fundido no interior da cavidade do molde treliça &quot;laminar&quot;. <p class=...

Metais celulares são os metais composta de uma rede interligada de suportes sólidos ou placas e têm micro-arquiteturas complexas com vazios 1. Exemplos incluem tanto i) as espumas estocásticas estruturados de forma aleatória e ii) periodicamente ordenada bidimensionais (2D) favos de mel e tridimensionais (3D estruturas de treliça) treliçadas. Eles têm recebido atenção devido à sua elevada rigidez específica e força 1-3 e alta resistência específica 4-5, excelente absorção de energia para a carga de impacto 6, isolamento acústico 7, possível desenho de dissipadores de calor e trocadores de calor 8. Especialmente, estruturas de rede cristalina periodicamente ordenadas têm o potencial para manipular as propriedades superiores com uma capacidade para controlar a geometria da rede porosa interna. Devido à sua geometria complexa rede porosa interna, é difícil de fabricar metais celulares usando o machinin subtractiva convencionalg. Como tal, os investigadores começaram a procurar métodos alternativos para fabricar metais celulares: formação de gás no metal líquido ou a mistura de pó de metal com agentes de expansão foram exploradas para a fabricação de formas de metal estocásticos 9. Devido à falta de controlo sobre a topologia de células, é difícil para adaptar as propriedades mecânicas. Alternativamente, os métodos de fabricação de metais celulares periodicamente pedidos foram exploradas: carimbar folhas finas de metal em uma forma ondulada seguido de juntá-las para criar estruturas periódicas 10, bonding fenda folhas de metal 11, extrusão 12, tecelagem e em chamas filamentos de metal para fabricar têxteis 13. Embora estes métodos de fabrico oferecem padrões repetitivos, os padrões são ainda limitados na direcção planar. Em um esforço para gerar padrão de repetição 3D, os pesquisadores começaram a usar fabricação aditiva (AM); por exemplo, Selective Laser de fusão (SLM) 14, Electron Beam Melting (EBM) <sup&gt; 15, e Direct-Metal Laser Sintering (LMG) 16. Apesar de sua capacidade para fabricar 3D ordenou geometrias de treliça complexos, ainda existem algumas limitações: dificuldade em utilizar metais com alta condutividade térmica e alta refletividade óptico 17, de alta tensão residual térmica 18, acabamento de superfície pobre com o fenômeno &quot;balling&quot; durante a laser ou de elétrons de fusão 19, propriedades anisotrópicas 20-21 de peças causadas por um efeito combinado da fabricação de camadas, formação anisotrópica de grãos, tamanho de pó, potência e velocidade de varredura de laser ou feixe de electrões 15, alto consumo de energia, etc. Combinando polímero AM base com fundição de metais pode fornecer um método alternativo para a fabricação de metais treliça. Pode-se chamar isso de &quot;AM indireta&quot;. Indirecta AM pode fornecer uma solução para superar os problemas técnicos de AM directa dos metais acima mencionados. Vários esforços têm sido made fabricar metais treliça usando indireta SOU combinando impressão 3D de polímeros com gravidade baseada fundição 22-25; por exemplo, uma carcaça de investimento combinado com modelagem por fusão e deposição (FDM) para fabricar uma liga de malha 22-25 ou areia de fundição combinado com um pó de areia com base AM 23. O casting base gravidade parece continuar a ser um desafio técnico para superar - misrun e porosidade causada por súbita solidificação de metais fundidos quando eles se encontram estruturas de rede com cantos afiados de moldes estruturais treliça 25-26. Relativamente grande área de superfície de moldes estruturais treliçadas também parece contribuir para arrefecimento brusco, resultando na solidificação prematura 25-26. Neste estudo, propomos uma AM indireta alternativa que pode superar a misrun durante a fabricação de metais treliça - Fundição centrífuga para uma cavidade do molde treliça feita por um padrão de polímero sacrificial estrutura 3D impresso. Nós usamos uma câmera digitalLight Processing (DLP) com base método de impressão 3D para construir um padrão sacrificial estrutural estrutura seguido de fundição centrífuga de ligas de Al e Cu. O objectivo deste estudo é o de proporcionar um protocolo detalhado na fabricação de metais treliça 3D que têm uma forma complexa e uma espessura de parede fina. A principal contribuição deste processo é fornecer uma oportunidade para alargar a selecção de materiais com baixo custo de produção para a fabricação de metais treliça.

<table><tbody><tr><td>Motorized centrifugal casting machine</td><td>Rey Motorized Centrifugal Casting Machine, Rey Industries Inc.</td><td></td><td>Made in U.S.A. by Rey industries, Inc. Dallas, TX 75220</td></tr><tr><td>Gypsum powder</td><td>Satin Cast 20, FindingKing Kerr</td><td>7960</td><td>Gypsum powder is used to make the investment mixture</td></tr><tr><td>Ployjet 3D printer</td><td>Projet HD3500 Plus, 3D Systems</td><td></td><td>This polymer based 3D printer to print out sacrificial pattern for casting.</td></tr><tr><td>Cartridge materials - UV curable and castable acrylic plastic</td><td>VisiJet Procast, 3D Systems</td><td></td><td>This is castable material that is going to be burn out before casting</td></tr><tr><td>Cartridge materials- support material</td><td>VijiJet S300, 3D Systems</td><td></td><td>This is support material that is going to be removed before pattern assemble</td></tr><tr><td>Ancient Bronze Casting Grain</td><td>Rio Grande</td><td>706051</td><td>This true bronze grain contains no zinc. Highly fluid, it melts quickly, casts cleanly and provides a good balance between strength and durability. The warm, deep-bronze color has rich red undertones, and the alloy takes a good patina.&lt;br/&gt; Composition is 90% copper with an amount of tin; fits into the CDA#90700 category. This grain is sold in 1 lb. packages.</td></tr><tr><td>Aluminum Round Wire, 1/8&quot;, 1-Lb. Spool, Dead Soft</td><td>Rio Grande</td><td>134700</td><td>Lightweight and strong, aluminum wire is an economical and versatile choice. Not as bright-white as silver, aluminum offers a warmer tone much like that of platinum. Solder ONLY with low-temp solders such as Stay-Brite; suitable for both pulse-arc and laser welding. This quality aluminum wire is packaged on 1 lb. spools.</td></tr><tr><td>Computer aided design software (Pro-e)</td><td></td><td></td><td>This software can be replaced with the others such as Auto CAD, Catia, and so on.</td></tr><tr><td>ProJet Finisher 1-A</td><td>3D Systems</td><td></td><td>This machine is used to melt the support material.</td></tr><tr><td>160 Watt 2.5 Liters Digital Ultrasonic Cleaner with Timer Heater Rings Tools</td><td>Chicago, Electric, Power Tools</td><td></td><td>85 oz. capacity, Five cleaning cycles: 90, 180, 280, 380 and 480 seconds, Clean with or without heat, Easy-to-read LED digital timer, Clear-view window</td></tr><tr><td>Fan&amp;nbsp;</td><td>Honeywell Inc.&amp;nbsp;</td><td>HT-800</td><td>120 V A.C., 60 Hz., 0.85 A. TP</td></tr><tr><td>Paraffin wax for wax sheet - Modeler&#039;s Pink Wax Sheet, 3&quot; by 6&quot;, 24-Ga.</td><td>Rio Grande</td><td>700075</td><td>Sheet wax is flexible and can be cut or formed into any shape. It&amp;rsquo;s ideal for designing since you can draw or trace directly onto the sheet; choose green or pink depending on which will best show your designs. High manufacturing standards ensure exceptional consistency and significant price savings. Value is enhanced by larger package quantities at the same price as the smaller packages available elsewhere. Each 8-oz. package contains approximately 30 sheets.</td></tr><tr><td>Paraffin wax for wax stick - Modeler&#039;s Medium Red Sprue Wax, 8-Ga</td><td>Rio Grande</td><td>700741</td><td>A pliable, softer sprue wax than the firm blue. Good for forming gates and sprues and burns out cleanly with no residue.</td></tr><tr><td>Alcohol Lamp</td><td>Rio Grande</td><td>700008</td><td>Use this lamp to heat wax-working tools or as a flame polisher. The heavy glass reservoir has faceted sides to allow it to be tipped for angling the flame. A screw adjustment for the 7&quot; x 3/16&quot; wick controls the height of the flame. A safety cap snuffs the flame and prevents fuel evaporation. For the best flame, use methyl alcohol fuel. Replacement wicks available. Reservoir holds 5 oz. (150 ml) of fuel.</td></tr><tr><td>Wax carving tool set - Soft Grip Wax Carvers, Set of 10</td><td>Rio Grande</td><td>700329</td><td>This boxed set offers the best in cutting and shaping technology. Each of these ten high-quality steel wax-carving tools features a 5/16&quot; PVC covered handle that ensures a sure, comfortable grip through hours of work and all have sharp edges for shaping and fine detailing. Sharpen or custom-shape each tool to fit your needs. These tools provide exceptional tool strength and deliver excellent results. This set comes in a hinged, foam-lined wood box.</td></tr><tr><td>Rubber Mixing Bowl, 1 - 1/2 Qt.</td><td>Rio Grande</td><td>702131</td><td>This highly-flexible vulcanized rubber bowl is easy to grip, will not be marred by a spatula and cleans with ease.</td></tr><tr><td>Pyrex Beaker, 1,000ml</td><td>Rio Grande</td><td>335040</td><td>Ideal for holding and heating bath plating solutions, this genuine Pyrex glass beaker is sturdy and durable.</td></tr><tr><td>Rio Premium Stainless Steel Flask, 2 - 1/2&quot; dia.</td><td>Rio Grande</td><td>70201514</td><td>This solid, #304-quality stainless steel flask is corrosion-resistant, durable for a long service life and performs under extreme temperature without distortion.</td></tr><tr><td>CAST/T Ceramic Casting Crucible, 450 g</td><td>Rio Grande</td><td>705047</td><td>Made exclusively for the CAST/T centrifugal casting machine, this crucible is designed with an angled base that slides into the hinged bracket on top of the casting machine. This brings the crucible into perfect alignment with the center of the flask ring to ensure an error-free pour.</td></tr><tr><td>MyWeigh iBalance 300 Digital Scale</td><td>Rio Grande</td><td>116850</td><td>This scale is used to measure the weight of the sacrificial and sprue system for metal which is going to be used for centrifugal casting.</td></tr><tr><td>Rubber bottom - CAST/T Flask Ring Base</td><td>Rio Grande</td><td>705025</td><td>Specially made for the CAST/T centrifugal casting machine, this rubber base accommodates all Table King flask ring styles, creating a secure, airtight seal throughout the investment process. The center post fits either of the wax disc styles for complete versatility.</td></tr><tr><td>Scotch&amp;reg; Colored Duct Tape, 1 7/8&quot; x 20 Yd., Blue</td><td>OfficeMax&amp;nbsp;</td><td>22353766</td><td>This scotch tape is used to make sure that the gypsum-water mixture fully covers the assembled sacrificial pattern inside the flask by allowing for extra material above the flask height</td></tr><tr><td>Vacuum casting machine - V.I.C. 12 Tabletop Solid- and Perforated-Flask Casting Machine with The Rio Assistant, 110-Volt</td><td>Rio Grande</td><td>70511814</td><td>The V.I.C. 12 casting machine offers all the latest technical innovations for efficient, productive vacuum investing and casting. Designed to meet the demands of medium-sized casting operations, this machine includes a powerful 1/2 hp, 5cfm vacuum pump for effective vacuuming and outstanding casting results. The V.I.C. 12 casts small or large flasks. Includes an adapter table that accepts standard solid flasks up to 5&quot; x 7&quot; high and is mounted on rubber feet for stability.</td></tr><tr><td>Furnace for burn out sacrificial pattern -Rio Model 1000 Enameling Kiln with Nine Program Controller</td><td>Rio Grande</td><td>703121</td><td>The Rio enameling kiln features three pre-set firing temperatures for enamels and six that you can define. Use the exclusive Rio controller to set and maintain firing temperatures. Perfect for all types of enameling, including tall pieces. Includes ample space for firing and an easy-latch door that will not jar your enamels when opening and closing. Also suitable for metal clay, glass and ceramics. Galvanized steel case with high-temperature insulating firebrick keeps them cool. Element protected in recessed groove. Includes user instructions.</td></tr><tr><td>Smith Complete Little Torch Acetylene and Oxygen System</td><td>Rio Grande</td><td>500030</td><td>Get everything you need to equip your shop for soldering and brazing. Use Little Torch systems for gold&lt;br/&gt; or silver soldering, brazing and casting applications. Complete every soldering and melting job with confidence and ease! This system accepts all Little Torch accessory tips for melting, brazing and large soldering jobs and is a staple for every jeweler.</td></tr><tr><td>Heat-Resistant Safety Apron</td><td>Rio Grande</td><td>750160</td><td>The specially designed apron has an 800 &amp;deg;F (427 &amp;deg;C) temperature resistance. Its reflective finish repels hot metal splashes and helps insulate the wearer from heat.</td></tr><tr><td>Radnor Heat-Resistant Gloves</td><td>Rio Grande</td><td>350050</td><td>These flexible, heat-resistant gloves are ideal for enameling projects, allowing you to grip even small tongs securely. Blue, shoulder-split leather gloves are made of tough cowhide and lined with cotton and foam, and have reinforced thumb wings.</td></tr><tr><td>Platinum Soldering Glasses, #7</td><td>Rio Grande</td><td>113914</td><td>Protect yourself and your employees when soldering platinum. Comfortable glasses feature adjustable earpieces and 52mm IR green polycarbonate #7 lenses. The #7 lens is approved by The Platinum Guild.</td></tr><tr><td>Economy Light-Duty Flask Tongs</td><td>Rio Grande</td><td>704026</td><td>Constructed of bent steel, these tongs are designed to handle flasks 3-1/2&quot; or less in diameter. The small-angle notches grip smaller flask sizes and the larger, rounded contour area securely holds larger flasks.</td></tr><tr><td>Separating Screen Bucket</td><td>Rio Grande</td><td>201360</td><td>15&quot;-diameter, 11-1/2&quot;-deep</td></tr><tr><td>Sand blaster - Econoline - 101701CB-A - Free-Standing Cabinets Workspace Width (Inch): 60 Workspace Depth (Inch): 48</td><td>MSC industrial supply Co.&amp;nbsp;</td><td>223818</td><td>Ree-Standing Cabinets; Workspace Width (Inch): 60; Workspace Depth (Inch): 48; Workspace Height (Inch): 40; Air Requirement: 12 CFM @ 80 psi; Overall Cabinet Width (Inch): 65; Maximum Cabinet Depth (Inch): 86</td></tr><tr><td>Johnson&#039;s Baby Oil Shea &amp;amp; Cocoa Butter&amp;nbsp;</td><td>Wal-Mart</td><td>260074132</td><td>This baby&amp;nbsp; oil is used for removing the residue of the support material for the castable sacrificial pattern using Digital Ultrasonic Cleaner.</td></tr><tr><td>German 4&quot; Saw Frame and Saw Blade Kit</td><td>Rio Grande</td><td>110112</td><td>Quality, German-made frames are our most popular saw frames, and this frame includes a sampler pack of Rio German saw blades! The adjustable saw frame allows you to achieve the blade tension you want. Throat depth is 102mm (4&quot;). Saw blades have rounded backs that make cutting curves and corners easy and are made from hardened, tempered steel.</td></tr></tbody></table>

indirect fabrication of lattice metals with thin sections using centrifugal casting

Um dos métodos típicos para a fabricação de metais treliça 3D é o processo em metal direta manufatura aditiva (AM), tais como Selective Laser de fusão (SLM) e Electron Beam Melting (EBM). Apesar da sua potencial capacidade de processamento, o método directo AM tem várias desvantagens tais como elevado custo, acabamento de superfície pobre de produtos finais, limitação na selecção de materiais, o stress térmico elevado, e propriedades anisotrópicas de peças. Propomos um método de baixo custo para a fabricação de metais treliça 3D. O objectivo deste estudo é o de proporcionar um protocolo detalhado na fabricação de metais treliça 3D que têm uma forma complexa e uma espessura de parede fina, por exemplo, fardo octeto feito de ligas de Al e Cu possuindo um comprimento de célula unitária de 5 mm e uma espessura de parede celular de 0,5 mm. Um procedimento experimental geral é dividido em oito seções: (a) a impressão 3D de padrões de sacrifício (b) derreter-out de materiais de apoio (c) a remoção de resíduos de materiais de apoio (d) assembl padrãoy (e) investimentos (f) burn-out de padrões de sacrifício (g) de fundição centrífuga (h) de pós-processamento para os produtos finais. A técnica AM indireta sugeriu oferece o potencial para a fabricação de metais treliça ultra-leves;., Por exemplo, estruturas de rede com ligas de alumínio. Verifica-se que os parâmetros do processo devem ser adequadamente controlada dependendo dos materiais e da geometria da estrutura, observando-se os produtos finais de metais octeto do fardo através da técnica indirecta AM.

Usando o fabrico aditivo indirecta descrito na secção protocolo, Al e Cu ligas foram usadas para metais fabricação octeto do fardo, como se mostra na Figura 1 O procedimento de moldagem inteira é resumido na Figura 2 O procedimento consiste em oito secções:.. (A) sacrificial padrão de impressão (b) fusão-out de material de apoio (c) a remoção de resíduos de material de apoio (d) O conjunto padrão (e) investimentos (f) burn-out de padrões d...

Watch this Scientific Journal Video about Indirect Fabrication of Lattice Metals with Thin Sections Using Centrifugal Casting at JoVE.com

Indirect Fabrication of Lattice Metals with Thin Sections Using Centrifugal Casting

Um método de fabrico aditivo indirecta combinando uma impressão em 3D de polímeros com uma fundição centrífuga é delineado para o fabrico de metais treliça octeto 3D (Al e Cu ligas) com um comprimento de célula unitária de 5 mm com uma espessura de parede de 0,5 mm.

Fabrication indireta de Malha Metals com cortes finos Usando Fundição

One of the typical methods to manufacture 3D lattice metals is the direct-metal additive manufacturing (AM) process such as Selective Laser Melting (SLM) ...

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12.4K visualizações.  University of North Texas.  Um método de fabrico aditivo indirecta combinando uma impressão em 3D de polímeros com uma fundição centrífuga é delineado para o fabrico de metais treliça octeto 3D (Al e Cu ligas) com um comprimento de célula unitária de 5 mm com uma espessura de parede de 0,5 mm. 

Vídeo: Indirect Fabrication of Lattice Metals with Thin Sections Using Centrifugal Casting

Fabricating Metamaterials Using the Fiber Drawing Method

Metamaterials are man-made composite materials, fabricated by assembling components much smaller than the wavelength at which they operate 1. They owe their electromagnetic properties to the structure of their constituents, instead of the atoms that compose them. For example, sub-wavelength metal wires can be arranged to possess an effective electric permittivity that is either positive or negative at a given frequency, in contrast to the metals themselves 2. This unprecedented control over the behaviour of light can potentially lead to a number of novel devices, such as invisibility cloaks 3, negative refractive index materials 4, and lenses that resolve objects below the diffraction limit 5. However, metamaterials operating at optical, mid-infrared and terahertz frequencies are conventionally made using nano- and micro-fabrication techniques that are expensive and produce samples that are at most a few centimetres in size 6-7. Here we present a fabrication method to produce hundreds of meters of metal wire metamaterials in fiber form, which exhibit a terahertz plasmonic response 8. We combine the stack-and-draw technique used to produce microstructured polymer optical fiber 9 with the Taylor-wire process 10, using indium wires inside polymethylmethacrylate (PMMA) tubes. PMMA is chosen because it is an easy to handle, drawable dielectric with suitable optical properties in the terahertz region; indium because it has a melting temperature of 156.6 &deg;C which is appropriate for codrawing with PMMA. We include an indium wire of 1 mm diameter and 99.99% purity in a PMMA tube with 1 mm inner diameter (ID) and 12 mm outside diameter (OD) which is sealed at one end. The tube is evacuated and drawn down to an outer diameter of 1.2 mm. The resulting fiber is then cut into smaller pieces, and stacked into a larger PMMA tube. This stack is sealed at one end and fed into a furnace while being rapidly drawn, reducing the diameter of the structure by a factor of 10, and increasing the length by a factor of 100. Such fibers possess features on the micro- and nano- scale, are inherently flexible, mass-producible, and can be woven to exhibit electromagnetic properties that are not found in nature. They represent a promising platform for a number of novel devices from terahertz to optical frequencies, such as invisible fibers, woven negative refractive index cloths, and super-resolving lenses.

Metamaterials at terahertz frequencies offer unique opportunities, but are challenging to fabricate in bulk. We adapt the fabrication procedure for microstructured polymer optical fibers to inexpensively fabricate metamaterials potentially on an industrial scale. We produce polymethylmethacrylate fibers containing ~10 &mu;m diameter indium wires separated by ~100 &mu;m, which exhibit a terahertz plasmonic response.

Os metamateriais usando o método de fabricação Desenho de Fibra

Metamaterials are man-made composite materials, fabricated by assembling components much smaller than the wavelength at which they operate 1. They owe ...

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A Method to Fabricate Disconnected Silver Nanostructures in 3D

The standard nanofabrication toolkit includes techniques primarily aimed at creating 2D patterns in dielectric media. Creating metal patterns on a submicron scale requires a combination of nanofabrication tools and several material processing steps. For example, steps to create planar metal structures using ultraviolet photolithography and electron-beam lithography can include sample exposure, sample development, metal deposition, and metal liftoff. To create 3D metal structures, the sequence is repeated multiple times. The complexity and difficulty of stacking and aligning multiple layers limits practical implementations of 3D metal structuring using standard nanofabrication tools. Femtosecond-laser direct-writing has emerged as a pre-eminent technique for 3D nanofabrication.1,2 Femtosecond lasers are frequently used to create 3D patterns in polymers and glasses.3-7 However, 3D metal direct-writing remains a challenge. Here, we describe a method to fabricate silver nanostructures embedded inside a polymer matrix using a femtosecond laser centered at 800 nm. The method enables the fabrication of patterns not feasible using other techniques, such as 3D arrays of disconnected silver voxels.8 Disconnected 3D metal patterns are useful for metamaterials where unit cells are not in contact with each other,9 such as coupled metal dot10,11or coupled metal rod12,13 resonators. Potential applications include negative index metamaterials, invisibility cloaks, and perfect lenses.
In femtosecond-laser direct-writing, the laser wavelength is chosen such that photons are not linearly absorbed in the target medium. When the laser pulse duration is compressed to the femtosecond time scale and the radiation is tightly focused inside the target, the extremely high intensity induces nonlinear absorption. Multiple photons are absorbed simultaneously to cause electronic transitions that lead to material modification within the focused region. Using this approach, one can form structures in the bulk of a material rather than on its surface.
Most work on 3D direct metal writing has focused on creating self-supported metal structures.14-16 The method described here yields sub-micrometer silver structures that do not need to be self-supported because they are embedded inside a matrix. A doped polymer matrix is prepared using a mixture of silver nitrate (AgNO3), polyvinylpyrrolidone (PVP) and water (H2O). Samples are then patterned by irradiation with an 11-MHz femtosecond laser producing 50-fs pulses. During irradiation, photoreduction of silver ions is induced through nonlinear absorption, creating an aggregate of silver nanoparticles in the focal region. Using this approach we create silver patterns embedded in a doped PVP matrix. Adding 3D translation of the sample extends the patterning to three dimensions.

Femtosecond-laser direct-writing is frequently used to create three-dimensional (3D) patterns in polymers and glasses. However, patterning metals in 3D remains a challenge. We describe a method for fabricating silver nanostructures embedded inside a polymer matrix using a femtosecond laser centered at 800 nm.

Um método para fabricar nanoestruturas de prata desconectados em 3D

The standard nanofabrication toolkit includes  techniques primarily aimed at creating 2D patterns in dielectric media. Creating  metal patterns on a ...

Process of Making Three-dimensional Microstructures using Vaporization of a Sacrificial Component

Vascular structures in natural systems are able to provide high mass transport through high surface areas and optimized structure. Few synthetic material fabrication techniques are able to mimic the complexity of these structures while maintaining scalability. The Vaporization of a Sacrificial Component (VaSC) process is able to do so. This process uses sacrificial fibers as a template to form hollow, cylindrical microchannels embedded within a matrix. Tin (II) oxalate (SnOx) is embedded within poly(lactic) acid (PLA) fibers which facilitates the use of this process. The SnOx catalyzes the depolymerization of the PLA fibers at lower temperatures. The lactic acid monomers are gaseous at these temperatures and can be removed from the embedded matrix at temperatures that do not damage the matrix. Here we show a method for aligning these fibers using micromachined plates and a tensioning device to create complex patterns of three-dimensionally arrayed microchannels. The process allows the exploration of virtually any arrangement of fiber topologies and structures.

The Vaporization of a Sacrificial Component (VaSC) process is used to fabricate microvascular structures. This procedure uses sacrificial poly(lactic) acid fibers to form hollow microchannels with precise 3D geometric positioning provided by laser micromachined guide plates.

Processo de fabricação de microestruturas tridimensionais usando vaporização de um componente sacrificial

Vascular structures in natural systems are able to provide high mass transport through high surface areas and optimized structure. Few synthetic material ...

Fabrication of Spatially Confined Complex Oxides

Complex materials such as high Tc superconductors, multiferroics, and colossal magnetoresistors have electronic and magnetic properties that arise from the inherent strong electron correlations that reside within them. These materials can also possess electronic phase separation in which regions of vastly different resistive and magnetic behavior can coexist within a single crystal alloy material. By reducing the scale of these materials to length scales at and below the inherent size of the electronic domains, novel behaviors can be exposed. Because of this and the fact that spin-charge-lattice-orbital order parameters each involve correlation lengths, spatially reducing these materials for transport measurements is a critical step in understanding the fundamental physics that drives complex behaviors. These materials also offer great potential to become the next generation of electronic devices 1-3. Thus, the fabrication of low dimensional nano- or micro-structures is extremely important to achieve new functionality. This involves multiple controllable processes from high quality thin film growth to accurate electronic property characterization. Here, we present fabrication protocols of high quality microstructures for complex oxide manganite devices. Detailed descriptions and required equipment of thin film growth, photo-lithography, and wire-bonding are presented.

We describe the use of pulsed laser deposition (PLD), photolithography and wire-bonding techniques to create micrometer scale complex oxides devices. The PLD is utilized to grow epitaxial thin films. Photolithography and wire-bonding techniques are introduced to create practical devices for measurement purposes.

Fabricação de óxidos complexos espacialmente confinados

Complex materials such as high Tc superconductors, multiferroics, and colossal magnetoresistors have electronic and magnetic properties that arise from ...

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.

Fabricação de cavidades de nanoescala uniformes 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 ...

Preparation of Liquid-exfoliated Transition Metal Dichalcogenide Nanosheets with Controlled Size and Thickness: A State of the Art Protocol

We summarize recent advances in the production of liquid-exfoliated transition metal dichalcogenide (TMD) nanosheets with controlled size and thickness. Layered crystals of molybdenum disulphide (MoS2) and tungsten disulphide (WS2) are exfoliated in aqueous surfactant solution by sonication. This yields highly polydisperse mixtures containing nanosheets with broad size and thickness distributions. However, for most purposes, specific sizes (in terms of both lateral dimension and thickness) are required. For example, large and thin nanosheets are desired for (opto) electronic applications, while laterally small nanosheets are interesting for catalytic applications. Therefore, post-exfoliation size selection is an important step that we address here. We provide a detailed protocol on the efficient size selection in large quantities by liquid cascade centrifugation and the size and thickness quantification by statistical microscopic analysis (atomic force microscopy and transmission electron microscopy). The comparison of MoS2 and WS2 shows that both materials are size-selected in a similar way by the same procedure. Importantly, the dispersions of size-selected nanosheets show systematic changes in their optical extinction spectra with size due to edge and confinement effects. We show how these optical changes are related quantitatively to the nanosheets dimensions and describe how mean nanosheets length and layer number can be extracted reliably from the extinction spectra. The exfoliation and size selection protocol can be applied to a broad range of layered crystals as we have previously demonstrated for graphene, gallium sulphide (GaS) and black phosphorus.

A protocol for the liquid exfoliation of layered materials to nanosheets, their size selection and size measurement by microscopic and spectroscopic techniques is presented.

Preparação de líquido-esfoliada de metais de transição Dichalcogenide nanofolhas com Controlada tamanho e espessura: A State of the Art Protocolo

We summarize recent advances in the production of liquid-exfoliated transition metal dichalcogenide (TMD) nanosheets with controlled size and thickness. ...

Fabrication of Periodic Gold Nanocup Arrays Using Colloidal Lithography

Within recent years, the field of plasmonics has exploded as researchers have demonstrated exciting applications related to chemical and optical sensing in combination with new nanofabrication techniques. A plasmon is a quantum of charge density oscillation that lends nanoscale metals such as gold and silver unique optical properties. In particular, gold and silver nanoparticles exhibit localized surface plasmon resonances-collective charge density oscillations on the surface of the nanoparticle-in the visible spectrum. Here, we focus on the fabrication of periodic arrays of anisotropic plasmonic nanostructures. These half-shell (or nanocup) structures can exhibit additional unique light-bending and polarization-dependent optical properties that simple isotropic nanostructures cannot. Researchers are interested in the fabrication of periodic arrays of nanocups for a wide variety of applications such as low-cost optical devices, surface-enhanced Raman scattering, and tamper indication. We present a scalable technique based on colloidal lithography in which it is possible to easily fabricate large periodic arrays of nanocups using spin-coating and self-assembled commercially available polymeric nanospheres. Electron microscopy and optical spectroscopy from the visible to near-infrared (near-IR) was performed to confirm successful nanocup fabrication. We conclude with a demonstration of the transfer of nanocups to a flexible, conformal adhesive film.

We demonstrate the fabrication of periodic gold nanocup arrays using colloidal lithographic techniques and discuss the importance of nanoplasmonic films.

Fabricação de matrizes de periódicos Nanocup ouro usando litografia coloidal

Within recent years, the field of plasmonics has exploded as researchers have demonstrated exciting applications related to chemical and optical sensing ...

Processing of Bulk Nanocrystalline Metals at the US Army Research Laboratory

Given their potential for significant property improvements relative to their large grained counterparts, much work has been devoted to the continued development of nanocrystalline metals. Despite these efforts, the transition of these materials from the lab bench to actual applications has been blocked by the inability to produce large scale parts that retain the desired nanocrystalline microstructures. Following the development of a method proven to stabilize the nanosized grain structure to temperatures approaching that of the melting point for the given metal, the US Army Research Laboratory (ARL) has progressed to the next stage in the development of these materials - namely the production of large scale parts suitable for testing and evaluation in a range of relevant test environments. This report provides a broad overview of the ongoing efforts in the processing, characterization, and consolidation of these materials at ARL. In particular, focus is placed on the methodology used for producing the nanocrystalline metal powders, in both small and large-scale amounts, that are at the center of ongoing research efforts.

This paper provides a brief overview of the ongoing efforts at the Army Research Laboratory on the processing of bulk nanocrystalline metals with an emphasis on the methodologies used for the production of the novel metal powders.

Processamento de metais de nanocristalina em massa no exército E.U. Research Laboratory

Given their potential for significant property improvements relative to their large grained counterparts, much work has been devoted to the continued ...

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.

Fabricação de fundidos de filamento (FFF) de componentes de Metal-cerâmica

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

Fabrication of Magnetic Nanostructures on Silicon Nitride Membranes for Magnetic Vortex Studies Using Transmission Microscopy Techniques

Electron and x-ray magnetic microscopies allow for high-resolution magnetic imaging down to tens of nanometers. However, the samples need to be prepared on transparent membranes which are very fragile and difficult to manipulate. We present processes for the fabrication of samples with magnetic micro- and nanostructures with spin configurations forming magnetic vortices suitable for Lorentz transmission electron microscopy and magnetic transmission x-ray microscopy studies. The samples are prepared on silicon nitride membranes and the fabrication consists of a spin coating, UV and electron-beam lithography, the chemical development of the resist, and the evaporation of the magnetic material followed by a lift-off process forming the final magnetic structures. The samples for the Lorentz transmission electron microscopy consist of magnetic nanodiscs prepared in a single lithography step. The samples for the magnetic x-ray transmission microscopy are used for time-resolved magnetization dynamic experiments, and magnetic nanodiscs are placed on a waveguide which is used for the generation of repeatable magnetic field pulses by passing an electric current through the waveguide. The waveguide is created in an extra lithography step.

A protocol for the fabrication of magnetic micro- and nanostructures with spin configurations forming magnetic vortices suitable for transmission electron microscopy (TEM) and magnetic transmission x-ray microscopy (MTXM) studies is presented.

Fabricação de nanoestruturas magnéticas nas membranas de nitreto de silício para estudos de vórtice magnético utilizando técnicas de microscopia de transmissão

Electron and x-ray magnetic microscopies allow for high-resolution magnetic imaging down to tens of nanometers. However, the samples need to be prepared ...