这项研究从科研副校长及经济发展北德克萨斯大学的科研启动资助（RIG）（UNT）的支持。作者还感谢KCIS有限公司的部分支持这项研究。从PACCAR技术学院UNT这份出版物的成功的支持是极大的赞赏。

1.实验计划<ol><li>绘制使用计算机辅助设计（CAD）软件的牺牲图案（一个八位组桁架结构具有一浇道系统） 如图1和保存CAD模型为STL文件格式。 注:牺牲模式是八位桁架结构用直浇道系统，将最终被融化铸造的综合模式。因为牺牲图案包括两个八位字节桁架结构和浇道系统，它并不准确地表示八角体桁架本身。提供了牺牲图案的STL文件。记录由CAD软件所提供的牺牲花纹，这将被用于计算金属"质量的体积。 </li><li>打开连接到3D打印机打印图案的3D打印软件牺牲图案的CAD图纸。 </li><li>确保该三维打印机具有足够的UV可固化/可浇注丙烯酸塑料和支撑材料制成的蜡的在打印机墨盒。 </li></ol> 2，祭祀图案的制作<ol><li>制造组成的八角体桁架结构，并使用三维打印机（ 图2A - C）的浇道系统的牺牲花纹。 注意:在2.1.3过程 - 如果使用不产生辅助材料三维打印机2.1.7不是必需的。 <ol><li>发送所述牺牲图案的STL文件到3D打印机打印的牺牲图案（ 图2A）。 </li><li>融出在烘箱牺牲图案的支撑材料在高于载体材料的熔化温度（60 - 70 C）2小时（ 图2B）。 注:去除支撑材料的温度不宜过高。否则，可能会导致在牺牲图案的损坏。牺牲的模式开始在这一研究中围绕80℃越来越损坏。 注意:suppor的熔融温度ŧ材料对于可能使用不同的支持材料的3D打印机而异。 </li><li>填写婴儿油了数字超声波清洗机，以2.5升，最大音量的清洁剂可以包含（ 图2C）。 注:建议由3D打印机使用婴儿油，用于溶解蜡样支撑材料的残留量的供应商。 </li><li>把牺牲模式进入数字化超声波清洗机并打开吸尘器（ 图2C）的力量。确保牺牲图案中石油完全淹没。 </li><li>通过在65℃40分钟（ 图2C）浸渍在牺牲模式进入油中除去载体材料的残余物。 </li><li>从清洁器取出所​​述牺牲花纹如果支撑材料被完全去除。 </li><li>有牺牲图案干后用在室温（〜20℃）（ 图2C）的风扇。 注意:这需要约2小时直到牺牲图案的表面上的油已完全干燥。考虑如果表面是不发粘被完全干燥所述牺牲花纹。 </li></ol></li></ol> 3.模具的制作<ol><li> 模型组件 <ol><li>附加一个橡胶垫圈至牺牲图案（的八角体桁架的浇道系统），并把它们放在一个圆筒形烧瓶中的与6.35厘米的高度，直径6.35厘米（ 图2D）的底部。 注:准备两个瓶中铸造各种金属; Al和Cu合金。 </li><li>双重检查与牺牲花纹的橡胶垫被完全附连到该烧瓶的底部。 </li><li>换用胶带烧瓶，使投资粉末 - 水混合物，其过程将在接下来的部分中描述的，可以不从烧瓶中漏出。 </li></ol></li><li> 投资模具的研制 <ol><li>准备投资粉末（卡索4 </sUB&gt;，ρ= 1019公斤/米3）89克，这是87.16毫升。使用规模称重投资粉末。 注意:投资粉末的物理性能列于表1中。 </li><li>倒入投资粉放入搅拌碗（1升）。 </li><li>将水（114毫升）到混合碗中。用烧杯，以测量水的体积。 </li><li>混合与水投资粉末在碗3分钟。拌匀，直到有在投资粉末与水的混合物没有肿块。否则，可能会导致投资模具的表面质量较差。按照工作流， 如图3。 </li><li>为了在该混合物中以除去气泡，碗放置在一个真空室中90秒，直到气泡不能在用裸眼（ 图3）的混合物中可以看出。 </li><li>将混合物倒入一个烧瓶中嵌入所述牺牲图案和橡胶垫圈（ 图2E）。 </li><li>放置FLAS再次K的真空室90秒以除去混合物（图3）内的气泡的残留物。 </li><li>干燥该混合物的烧瓶内，直到它在RT（ 图3）硬化。 注:一般情况下，大约需要10 - 15分钟的在RT硬化混合物。 </li><li>在该混合物的烧瓶内的底部取出烧瓶和橡胶垫圈一旦混合物硬化（ 图3）。此产品可以被称为石膏模具。 </li></ol></li><li> 烧完 <ol><li>而下列加热和冷却时间表（ 图4）加热从23至150℃，在2.1℃/分钟建立一个烧尽时间在炉; 150在3.7℃/ min的370℃; 370以1.85℃/分钟480℃; 480以4.17℃/分钟730℃; 730℃1小时;在-4.17℃/ min冷却730 480℃。 注:燃尽VAR的时间IES用烧瓶大小。在这项研究中，设置燃尽时间为6小时。 </li><li>放置在炉中（ 图2F）的石膏模具。 </li><li>打开炉中，在炉子增加温度以除去石膏模具内的牺牲花纹。按照图4中的温度条件。 注意:由于UV固化/浇注丙烯酸塑料，牺牲图案的材料，是一种热固性丙烯酸类聚合物的塑料，它不流动，但解离到在炉内气相。 </li></ol></li><li> 离心铸造 （ 图2G） <ol><li>检查离心铸造机的使用手臂打开离心铸造机的电源后，转速表与转速42​​5的角速度旋转。 </li><li>准备了可以容纳150克合金熔化两个陶瓷坩埚。使用的铝和铜合金坩埚分开以防止它们被污染随eACH的。 </li><li>打开离心铸造机的电源。 </li><li>使用金​​属切割机，印章的合金与10件 - 20mm的长度。制备它们足以完全填充模腔，其量应是相同的牺牲花纹。 注意:需要填写模腔的相同体积的金属的质量而变化考虑每个金属变化的密度。 </li><li>穿阻燃布和手套和护目镜。准备在室温一桶水（30升）。 </li><li>以石膏模从炉暂时缺货3.3节，在烧瓶摇篮安装和平衡离心铸造机（ 图5）的手臂。 </li><li>浇铸前放置石膏模返回到炉和预热到482℃。 </li><li>放置在坩埚中的坩埚座（ 图5）。 </li><li>把切碎合金到坩埚。 </li><li>打开氧气的阀罐用氧 - 乙炔焊炬连接并保持在96.5千帕（14磅）的罐中的压力水平。 </li><li>点燃氧 - 乙炔焊炬用打火机并通过调节气体的混合控制火焰的强度。 注意:使用氧 - 乙炔火炬时需要注意。其火炬的最高温度约为1200℃。 </li><li>与坩埚中的火炬熔化切碎合金（Al合金或Cu合金），直到合金完全变成液体。 </li><li>搅拌坩埚中的合金用碳棒直到切碎合金完全熔化。 </li><li>放置在烧瓶摇篮石膏模具后靠旁边含有熔融合金（ 图5）的坩埚中。 </li><li>关闭离心铸造机的盖子，让手臂离心旋转，并至少等待3分钟。 注意:离心铸造设备开始尽快铸造机盖关闭操作。离心手臂在425 rpm的速度对应于在所述牺牲图案的模腔中的入口速度旋转时，V R = 8.03Hz米/秒28 29在图5中，其中入口速度是使用宏观粒子动力学从角度计算离心铸造的速度臂28,29。 </li><li>关闭离心铸造机的功率臂​​的3分钟后旋转。 </li><li>打开连铸机的盖子。 </li><li>以石膏模出使用钳瓶摇篮。 </li><li>保持在RT模具15 - 20分钟，直到熔融合金的颜色回到它原来的一个在固相上。 </li><li>使用钳，淬火在水中的石膏模在RT放置在一个桶（30升）约5分钟。确保该石膏模具的温度接近室温淬火后。 </li><li>为了获得在模具内的晶格金属，溶解模具在水中。石膏的模具很容易在水中溶解。 </li></ol></li></ol> 4.后置处理八角桁架金属的最终产品<ol><li>打开一个喷砂的电源。 </li><li>放置喷砂内的平台上的八角体桁架的金属和关闭机器的门。 </li><li>戴上手套和抢喷砂手枪。 </li><li>抓住金属制品的浇道部，并与喷砂2小时从晶格金属吹熄残余石膏。 注意:喷砂的强度自动在550千帕大约固定。一旦喷砂被操作时，则空气从手枪自动退出。 </li><li>保持喷砂运行，直到八角体桁架金属内部的投资石膏渣完全，而用肉眼检查去除。 注:上没有拆除石膏渣的微观标准。这超出了本研究的范围。 ŧ他除去石膏残余物容易用肉眼确定。因为八角体桁架是一个开放的单元结构，可以看到，通过并检查是否石膏残留物完全除去。 需要使用喷砂不与在高压（550千帕）的薄壁厚度（0.5mm）的损坏八角体桁架金属注意:注意。 </li><li>如果该八位位组桁架金属内的投资石膏残余物未完全与喷砂除去，使用附加的后处理的方法; 例如 ，超声波清洗或离开产品在水中一天。 </li><li>在使用超声清洁器的情况下，填充0.7升的水进入超声波清洗，并将与石膏渣八角体桁架金属在超声波清洗器。 <ol><li>打开的超声波洗涤机的功率。 </li><li>设置一个操作条件; 例如，在70℃3小时。 </li><li>取八角体桁架金属出的超声波洗涤机的一次次E操作结束。 </li><li>干燥在RT的八角体桁架金属直到在金属表面上的水完全除去。 </li></ol></li><li>作为一种替代的后处理方法，留在水中的八角体桁架金属。这将导致石膏剩余物溶解于水。 <ol><li>放置八角体桁架金属与水的石膏渣和离开它一天，使得投资石膏和金属表面之间的结合力变得减弱在水中。 </li><li>就拿八角体桁架金属出来的水。 </li><li>干燥在RT的八角体桁架金属直到在金属表面上的水完全除去。 </li></ol></li><li>使用锯或其它适当的工具，切断填充浇道系统的一部分的空腔中的金属从金属制品中，用一个大小为25mm×25mm的×25mm的获得最终的八角体桁架金属， 如图1B所示 。 </li></ol>

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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Numerical+Study+of+Molten+Aluminum+for+Investment+Casting+of+3D+Cellular+Metals.">A Numerical Study of Molten Aluminum for Investment Casting of 3D Cellular Metals.</a> Proceedings of the ASME International Mechanical Engineering Congress and Exposition. , (2013).</li><li>Mun, J., Yun, B. -. G., Ju, J., Chang, B. -. M. <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+of+a+Periodic+3D+Cellular+Metal+-+Flow+Simulation+of+Molten+Aluminum+Alloy.">Indirect Additive Manufacturing Based Casting of a Periodic 3D Cellular Metal - Flow Simulation of Molten Aluminum Alloy.</a> Manufact. 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.

对于传统的金属铸件，它以保持熔融金属的流动顺畅，并在模腔"层状"精简，而避免不规则和搅拌流中紊流27一般观察是很重要的。因此，正确设计用离心臂的旋转速度，以保持熔融金属的晶格型腔&#39;层&#39;内的流相关联的浇道系统的入口是重要的。 在这项研究中，该协议的关键步骤是与水，烧尽牺牲图案的投资粉末的混合中，并且离心铸造工艺。投资粉末与水的混?...

蜂窝金属是固体支柱或板的互连网络的组成的金属和具有复杂的微观结构用1空隙。示例包括ⅰ）无规结构随机泡沫和ii）定期有序二维（2D）的蜂窝体和三维（3D）晶格桁架结构。他们已受到关注，因为它们高的比刚度和强度1-3和高比回弹4-5，对于冲击载荷6，隔音7，热消散器和热交换器8的可能的设计优良的能量吸收。特别地，周期性有序晶格结构具有工程师优于与控制内部多孔网络的几何形状的能力的属性的潜力。 由于其复杂的内部多孔网络的几何形状，则难以用传统的减色machinin制造蜂窝金属G。因此，研究人员已经开始寻找替代方法来制作蜂窝金属:液态金属成形气体或金属粉末与发泡剂混合进行了探讨制造随机金属形式9。由于缺乏对细胞拓扑控制的，这是很难调整机械性能。可替代地，用于周期性地有序蜂窝金属的制造方法进行了探讨:冲压金属薄板为波纹形，随后通过加入它们来创建周期性结构10，接合开槽金属片11，挤出12，编织和炽热金属丝来制造纺织品13。即使这些制造方法提供可重复的图案，所述图案在所述平面方向上仍然受到限制。在努力产生三维图案重复，研究人员使用添加剂制造（AM）开始; 例如 ，选择性激光熔化（SLM）14，电子束熔炼（EBM） <sup&gt; 15，和直接金属激光烧结（DMLS）16。尽管他们的能力来制造三维有序复杂晶格的几何形状，但仍存在一些限制:激光或电子熔化期间使用具有高导热性和高的光反射率17，高热残余应力18，表面光洁度较差的"成球"的现象金属困难19，各向异性特性引起的分层制造，各向异性地层颗粒，粉末的尺寸，功率和激光或电子束15，高能耗等扫描速度的组合效果份20-21。 结合系聚合物调幅与金属铸件可以提供制造晶格金属的替代方法。人们可以把这种"间接AM"。间接调幅可以提供一种解决方案，以克服上述金属的直接调幅的技术问题。一些努力是马例如 ，熔模铸造与熔融沉积成型（FDM）组合制作晶格合金22-25或砂型铸造用沙粉末组合;德使用间接AM结合基于重力铸造22-25的聚合物的三维印刷制造晶格金属根据今年23岁 。重力铸造的基础似乎仍然是一个技术挑战，克服-浇不足和气孔引起熔融金属凝固突然见面时晶格结构模具25-26的尖角网络结构。晶格结构的模具的相对大的表面面积也似乎有助于突然冷却，导致过早凝固25-26。 在这项研究中，我们提出了制造晶格金属过程中可能会克服浇不足替代间接AM - 离心浇铸到由​​3D印刷格子牺牲聚合物图案制成的格子模腔。我们使用数字光处理（DLP）的3D打印方法建立一个格子结构牺牲图案其次是铝和铜合金的离心铸造。本研究的目的是提供在具有复杂形状和薄壁三维晶格金属制造的详细协议。这个过程的主要贡献是提供一个机会以低生产成本延长材料的选择制造格子金属。

<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

其中一个典型的方法来制造三维晶格金属是直接金属添加剂制造（AM）的过程，如选择性激光熔化（SLM）和电子束熔炼（EBM）。尽管其潜在的处理能力时，直接调幅方法有几个缺点，如成本高，最终产品的表面光洁度差，限制在材料的选择，高的热应力，以及零件的​​各向异性性质。我们提出了一种经济有效的方法来制造三维晶格金属。本研究的目的是提供在具有复杂形状和薄壁三维晶格金属制造的详细协议; 例如 ，八角体桁架由具有5mm的单元电池的长度和细胞壁厚度的Al和Cu的合金的为0.5mm。整体实验过程分为八个部分:（一）祭祀图案的三维打印（二）融出辅助材料（C）去除支撑材料的残留量（四）模式assemblY（五）投资（F）烧坏牺牲图案（G）离心铸造（H）后处理的最终产品。建议上午间接提供的技术来制造超轻金属晶格的潜力; 例如 ，网格结构用铝合金。看来，工艺参数应当根据材料和晶格几何适当地控制，由间接调幅技术观察八角体桁架金属的最终产品。

使用在协议部分中描述的间接添加剂制造中，使用铝和铜的合金制造八角体桁架的金属，如示于图1中的整个铸造过程总结于图2中的步骤包括八个部分:（一）的牺牲图案印刷（二）融出支持材料（c）去除支撑材料（D）模组件（五）投资（F）烧坏牺牲图案（G）离心铸造，及（h）的残留物的后处理。 如图3中的投资混合过程是为了确保...

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

间接添加剂的制造方法的聚合物的三维打印组合用离心铸造概述为具有0.5mm的壁厚5mm的单元电池的长度制造三维八角体桁架金属（Al和Cu合金）。

与超薄切片格金属制造间接使用离心铸造

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 次观看.  University of North Texas. 间接添加剂的制造方法的聚合物的三维打印组合用离心铸造概述为具有0.5mm的壁厚5mm的单元电池的长度制造三维八角体桁架金属（Al和Cu合金）。 

视频: 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.

制造超材料使用光纤拉丝法

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

科研

工程学

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.

一个断开连接的银纳米结构的方法来制作的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.

制作三维微结构，用牺牲部分汽化过程

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.

空间密闭的复合氧化物制备

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.

通过硅直接晶圆粘接制造均匀纳米级腔

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.

与尺寸可控液体剥离的过渡金属二硫属化物纳米片和厚度的制备:艺术议定书的国家

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.

用胶体光刻制备周期性金 Nanocup 阵列

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.

美国陆军研究实验室散装纳米晶金属的加工

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.

金属陶瓷元件的熔融长丝制造 (fff)

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.

用透射显微技术制备氮化硅薄膜磁性纳米结构的研究

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