与超薄切片格金属制造间接使用离心铸造
Summary
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）。
Abstract
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。
Introduction
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> 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。
Protocol
1.实验计划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?…
Representative Results
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?…
Discussion
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'层'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…
Disclosures
The authors have nothing to disclose.
Acknowledgements
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。
Materials
| Motorized centrifugal casting machine | Rey Motorized Centrifugal Casting Machine, Rey Industries Inc. | Made in U.S.A. by Rey industries, Inc. Dallas, TX 75220 | |
| Gypsum powder | Satin Cast 20, FindingKing Kerr | 7960 | Gypsum powder is used to make the investment mixture |
| Ployjet 3D printer | Projet HD3500 Plus, 3D Systems | This polymer based 3D printer to print out sacrificial pattern for casting. | |
| Cartridge materials – UV curable and castable acrylic plastic | VisiJet Procast, 3D Systems | This is castable material that is going to be burn out before casting | |
| Cartridge materials- support material | VijiJet S300, 3D Systems | This is support material that is going to be removed before pattern assemble | |
| Ancient Bronze Casting Grain | Rio Grande | 706051 | 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. Composition is 90% copper with an amount of tin; fits into the CDA#90700 category. This grain is sold in 1-lb. packages. |
| Aluminum Round Wire, 1/8", 1-Lb. Spool, Dead Soft | Rio Grande | 134700 | 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. |
| Computer aided design software (Pro-e) | This software can be replaced with the others such as Auto CAD, Catia, and so on. | ||
| ProJet Finisher 1-A | 3D Systems | This machine is used to melt the support material. | |
| 160 Watt 2.5 Liters Digital Ultrasonic Cleaner with Timer Heater Rings Tools | Chicago, Electric, Power Tools | 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 | |
| Fan | Honeywell Inc. | HT-800 | 120V A.C., 60Hz., 0.85A. TP |
| Paraffin wax for wax sheet – Modeler's Pink Wax Sheet, 3" by 6", 24-Ga. | Rio Grande | 700075 | Sheet wax is flexible and can be cut or formed into any shape. It’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. |
| Paraffin wax for wax stick – Modeler's Medium Red Sprue Wax, 8-Ga | Rio Grande | 700741 | A pliable, softer sprue wax than the firm blue. Good for forming gates and sprues and burns out cleanly with no residue. |
| Alcohol Lamp | Rio Grande | 700008 | 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" x 3/16" 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. (150ml) of fuel. |
| Wax carving tool set – Soft Grip Wax Carvers, Set of 10 | Rio Grande | 700329 | 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" 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. |
| Rubber Mixing Bowl, 1-1/2 Qt. | Rio Grande | 702131 | This highly-flexible vulcanized rubber bowl is easy to grip, will not be marred by a spatula and cleans with ease. |
| Pyrex Beaker, 1,000ml | Rio Grande | 335040 | Ideal for holding and heating bath plating solutions, this genuine Pyrex glass beaker is sturdy and durable. |
| Rio Premium Stainless Steel Flask, 2-1/2" dia. | Rio Grande | 70201514 | This solid, #304-quality stainless steel flask is corrosion-resistant, durable for a long service life and performs under extreme temperature without distortion. |
| CAST/T Ceramic Casting Crucible, 450g | Rio Grande | 705047 | 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. |
| MyWeigh iBalance 300 Digital Scale | Rio Grande | 116850 | 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. |
| Rubber bottom – CAST/T Flask Ring Base | Rio Grande | 705025 | 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. |
| Scotch® Colored Duct Tape, 1 7/8" x 20 Yd., Blue | OfficeMax | 22353766 | 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 |
| Vacuum casting machine – V.I.C. 12 Tabletop Solid- and Perforated-Flask Casting Machine with The Rio Assistant, 110-Volt | Rio Grande | 70511814 | 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 1/2hp, 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" x 7" high and is mounted on rubber feet for stability. |
| Furnace for burn out sacrificial pattern -Rio Model 1000 Enameling Kiln with Nine Program Controller | Rio Grande | 703121 | 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. |
| Smith Complete Little Torch Acetylene and Oxygen System | Rio Grande | 500030 | Get everything you need to equip your shop for soldering and brazing. Use Little Torch systems for gold 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. |
| Heat-Resistant Safety Apron | Rio Grande | 750160 | The specially designed apron has an 800°F (427°C) temperature resistance. Its reflective finish repels hot metal splashes and helps insulate the wearer from heat. |
| Radnor Heat-Resistant Gloves | Rio Grande | 350050 | 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. |
| Platinum Soldering Glasses, #7 | Rio Grande | 113914 | 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. |
| Economy Light-Duty Flask Tongs | Rio Grande | 704026 | Constructed of bent steel, these tongs are designed to handle flasks 3-1/2" or less in diameter. The small-angle notches grip smaller flask sizes and the larger, rounded contour area securely holds larger flasks. |
| Separating Screen Bucket | Rio Grande | 201360 | 15"-diameter, 11-1/2"-deep |
| Sand blaster – Econoline – 101701CB-A – Free-Standing Cabinets Workspace Width (Inch): 60 Workspace Depth (Inch): 48 | MSC industrial supply Co. | 223818 | 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 |
| Johnson's Baby Oil Shea & Cocoa Butter | Wal-Mart | 260074132 | This baby oil is used for removing the residue of the support material for the castable sacrificial pattern using Digital Ultrasonic Cleaner. |
| German 4" Saw Frame and Saw Blade Kit | Rio Grande | 110112 | 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"). Saw blades have rounded backs that make cutting curves and corners easy and are made from hardened, tempered steel. |
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Cite This Article
Mun, J., Ju, J., Thurman, J. Indirect Fabrication of Lattice Metals with Thin Sections Using Centrifugal Casting. J. Vis. Exp. (111), e53605, doi:10.3791/53605 (2016).