遠心鋳造を使用した薄い部分との格子金属の間接製作
Summary
遠心鋳造を有するポリマーの3D印刷を組み合わせた間接的な添加剤の製造方法は、0.5mmの壁の厚さ5mmの単位セル長さを有する3次元オクテットトラス金属（AlとCuの合金）を製造するために概説されています。
Abstract
3D格子金属を製造する典型的な方法の1つは、選択的レーザ溶融（SLM）及び電子ビーム（EBM）溶融として直接金属添加物の製造（AM）プロセスです。その潜在的な処理能力にもかかわらず、直接AM方式は、高コスト、最終製品の貧弱な表面仕上げ、制限材料選択において、高い熱応力、および部品の異方性の性質のようないくつかの欠点があります。我々は、3次元格子金属を製造するためのコスト効果的な方法を提案します。本研究の目的は、複雑な形状と薄い壁厚を有する3次元格子金属の製造に関する詳細なプロトコルを提供することである5mmの単位セル長さとセル壁の厚さを有するAlとCuの合金で作られ、例えば 、オクテットトラス0.5mmの。 （a）は犠牲パターンの3D印刷（b）は、支持材料の溶融アウト（C）支持材料の残留物の除去（d）のパターンassembl：全体的な実験手順は、8つのセクションに分割されY（e）の投資（f）は、最終製品の犠牲パターン（g）の遠心鋳造（h）の後処理のバーンアウト。提案した間接的なAM技術は、超軽量の格子金属を製造する可能性を提供する。 例えば 、格子構造をAl合金で。間接的なAM技術によりオクテットトラス金属の最終生成物を観察し、プロセスパラメータを適切な材料及び格子形状に応じて制御する必要があると思われます。
Introduction
携帯金属が固体ストラットまたはプレートの相互接続されたネットワークで構成された金属であるとボイドとの複雑なマイクロアーキテクチャを有する1。例としては、I）ランダム構造確率フォームの両方を含む、およびii）周期的に2次元ハニカム三次元（3D）の格子トラス構造を命じました。彼らは、その高い比剛性と強度1-3と高い特定の弾力4-5、衝撃荷重6、防音7、熱放散と熱交換器8の可能な設計のための優れたエネルギー吸収に注目を集めています。特に、定期的に規則格子構造は、内部多孔性ネットワークの形状を制御する能力を有する優れた特性を設計する可能性を秘めています。
それらの複雑な内部多孔性ネットワークの形状には、従来のサブトラクティブmachininを用いた携帯金属を製造することは困難ですグラム。このように、研究者らは、細胞の金属を製造するための代替方法を探し始めている：液体金属中のガスを形成するか、発泡剤と金属粉末を混合確率的金属形態9を製造するために調べました。細胞のトポロジーの制御の欠如のため、機械的特性を調整することは困難です。また、定期的に注文した携帯金属の製造方法が模索された：周期構造10を作成するためにそれらを接合することにより、その後の波形形状に金属の薄いシートを打ち抜き、接合は繊維製品13を製造するために金属板11、押出12、織りや燃える金属フィラメントをスロット。これらの製造方法は、反復パターンを提供していても、パターンが依然として平面方向に制限されています。 3Dパターンの繰り返しを生成するための努力では、研究者は、添加剤製造（AM）を使用して開始し、 例えば 、選択的レーザ溶融（SLM）14、電子ビーム溶融（EBM） <sup> 15、およびダイレクトメタルレーザー焼結（DMLS）16。 3Dは、複雑な格子形状を注文製作する能力にもかかわらず、まだいくつかの制限が存在する：レーザー又は電子溶融中「ボーリング」現象と難易度の高い熱伝導性と高い光反射率17と金属を使用して、高い熱残留応力18、貧弱な表面仕上げを積層製造の複合効果による部品19、異方性20-21、粒子、粉末の大きさ、レーザまたは電子ビーム15のパワー及び走査速度、高いエネルギー消費などの異方性形成。
金属鋳造でポリマーベースのAMを組み合わせることで格子金属を製造する代替方法を提供することができます。一つは、この「間接AM」を呼び出すことができます。間接的なAMは、上記金属の直接AMの技術的問題を克服するための解決策を提供することができます。いくつかの努力がミリアンペアされていますデ22-25をキャストベースの重力を有するポリマーの3Dプリントを組み合わせた間接的なAMを使用して、格子の金属を製造する; 例えば 、熱溶解積層法（FDM）と組み合わせインベストメント鋳造法を砂の粉と合わせ格子合金22-25または砂型鋳造を製造するためにAM 23ベース。彼らは、格子構造の金型25から26の鋭い角を持つネットワーク構造を満たしたときに溶融金属の突然の凝固によって引き起こさ湯回り不良及び多孔性-重力系鋳造を克服するための技術的な課題を残っているように見えますが。格子構造の金型の比較的大きな表面積はまた、早期の凝固25-26に生じる、急激な冷却に寄与するように見えます。
3Dプリント格子犠牲ポリマーパターンによって作られた格子金型キャビティへの遠心鋳造 – 本研究では、格子金属の製造中湯回り不良を克服することができる代替間接AMを提案します。私たちは、デジタルを使います光処理（DLP）は、AlおよびCu合金の遠心鋳造に続いて格子構造犠牲パターンを構築するためのベースの3D印刷方法。本研究の目的は、複雑な形状と薄い壁厚を有する3次元格子金属の製造に関する詳細なプロトコルを提供することです。このプロセスの主な寄与は、格子金属を製造するための低コストで材料の選択範囲を拡張する機会を提供することです。
Protocol
実験1.計画 図1に示すように、コンピュータ支援設計（CAD）ソフトウェアを使用して犠牲パターン（スプルーシステムとのオクテットトラス構造）を描き、STLファイル形式としてCADモデルを保存します。 注：犠牲パターンは、最終的に鋳造するために溶融されるスプルーシステムとオクテットトラス構造の統合されたパターンです。犠牲パターンは、オクテットトラ?…
Representative Results
プロトコルセクションで説明した間接的な添加剤の製造を使用して、Al及びCuの合金は、図1に示すように、製造オクテットトラス金属のために使用された全体の鋳造手順は図2に要約されている手順では、8つのセクションで構成されています。。（a）の犠牲支持材料の残留物のパターン印刷（b）は、支持材料の溶融アウト（c）の除去（D）パ?…
Discussion
従来の金属鋳造のためには、金型キャビティの「層流」でスムーズかつ合理化溶融金属の流れを維持し、むしろ一般的に乱流27で観察された不規則な攪拌流を回避することが重要です。したがって、適切に格子モールドキャビティ「層状」内部の溶融金属の流れを維持するために遠心アームの回転速度に関連した湯口システムの注入口を設計することが重要です。
<p class="jove_content…Disclosures
The authors have nothing to disclose.
Acknowledgements
この研究は、ノーステキサス大学の研究と経済開発のための副社長の研究開始グラント（RIG）（UNT）から支援を受けました。著者らはまた、部分的に、この研究を支援するためのKCIS株式会社に感謝します。本書の成功にUNTでPACCAR技術研究所からのサポートが大幅に高く評価されています。
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).