Browse Topic: Casting

Items (669)
Find
Hard Anodic Coating of Magnesium AlloysAMS2466D (Current)12/9/2025
This specification covers the requirements for a hard anodic coating on magnesium alloys.
AMS B Finishes Processes and Fluids Committee
Aluminum Alloy, Castings 4.7Cu - 0.60Ag - 0.35Mn - 0.25Mg - 0.25Ti (B201.0-T7) Solution Heat Treated and Overaged AMS4242D (Current)12/9/2025
This specification covers an aluminum alloy in the form of castings.
AMS D Nonferrous Alloys Committee
Aluminum Alloy, Die Castings 8.5Si - 3.5Cu (A380.0-F) As Cast AMS4291K (Current)11/21/2025
This specification covers an aluminum alloy in the form of die castings.
AMS D Nonferrous Alloys Committee
Aluminum Alloy, Die Castings 9.5Si - 0.50Mg (360.0-F) As Cast AMS4290N (Current)11/21/2025
This specification covers an aluminum alloy in the form of die castings.
AMS D Nonferrous Alloys Committee
3D-PRINTING IMPACTS ON SYSTEMS ENGINEERING IN DEFENSE INDUSTRY2024-01-352711/15/2024
ABSTRACT Today’s combat vehicle designs are largely constrained by traditional manufacturing processes, such as machining, welding, casting, and forging. Recent advancements in 3D-Printing technology offer tremendous potential to provide economical, optimized components by eliminating fundamental process limitations. The ability to re-design suitable components for 3D-printing has potential to significantly reduce cost, weight, and lead-time in a variety of Defense & Aerospace applications. 3D-printing will not completely replace traditional processes, but instead represents a new tool in our toolbox - from both a design and a manufacturing standpoint.
Deters, Jason
Tolerance Relief on Transmissions Castings for ProducibilityF-0078-2022-175695/10/2022
ABSTRACT
Gimbutis, Brad, Palmer, Griffin, Beardsley, Justin, Quinn,  Holly
Aluminum Alloy, Castings 5.0Si - 1.2Cu - 0.50Mg (355.0-T51) Precipitation Heat TreatedAMS4210M (Current)4/22/2021
This specification covers an aluminum alloy in the form of castings.
AMS D Nonferrous Alloys Committee
Cast Aluminum Alloy Composite 4.6Cu - 3.4Ti - 1.4B - 0.75Ag - 0.27Mg (205.0/TiB2/3p-T7P) Investment Cast, Solution and Precipitation Heat TreatedAMS4471B (Historical)4/22/2021
This specification covers a dilute aluminum/TiB2 metal matrix composite in the form of investment castings.
AMS D Nonferrous Alloys Committee
Utilizing Casting Technologies on Legacy PartF-0076-2020-1627910/5/2020
Sikorsky has developed a specification outlining the use of three casting technologies: simulation, additive manufacturing of the mold and low pressure casting. This specification has been used in the past on new development projects with positive results, reducing lead times and number of pours to produce a useable part. When the S-92 program needed to develop a second source for a casting, they worked with Magellan Aerospace to implement the specification. The project proceeded on time with all castings able to be used. Some elements of the specification were modified to work with a legacy part design, including the use of statistical process controls to reduce variability in crucible pouring.
Woodworth, Heather, Featheringham, Andrew
Reducing Risk in 3D Printed Composite ToolingF-0076-2020-1628010/5/2020
For high end composite manufacturing in a rapid development environment, the long lead item is often the hard tooling, in particular the cure mold. A traditional metal mold takes in the neighborhood of four to nine months to design, fabricate and validate. With high temperature capable print materials, and larger and faster printers, Additive Manufacturing (AM) appears to have high potential in this area of advanced composites manufacturing. Sikorsky has used AM very successfully on a scale up to approximately 3'x3' and cure temperatures of 350°F. Though long-term durability is still to be determined; the materials, technologies, and techniques Sikorsky has employed for AM autoclave cure molds on this scale have consistently exceeded expectations. AM tools along the scale of main rotor blades could be leveraged to realize even more significant cost and schedule gains from AM autoclave tooling, and in this area, there are still more questions than answers when it comes to a dependable tooling solution. Rotorcraft development, in particular Future Vertical Lift (FVL), programs offer an opportunity to realize the significant schedule and cost benefits AM can provide for composite tooling.
Dunn, Eric
Theoretical Modeling of the Mechanical Degradation of Polymer Composites due to Moisture/Water Absorption and Damage Progression2019-01-13763/19/2019
The moisture/water absorption and microvoids/cracks progression are two well-understood mechanisms that have significant degradation effects on the mechanical properties/behaviors of the polymer-based composites. To theoretically investigate the effects of above two mechanisms, we develop a simple fiber reinforced polymer composites model by employing the internal state variable (ISV) theory. The water content and the anisotropically distributed damage of the composites are considered as two ISVs (the water content is described by a scalar variable and the damage is defined as a second order tensor) whose histories are governed by two specific physically-based evolution equations. The proposed model can be easily cast into a general theoretical framework to capture more polymer composites behaviors such as viscoelasticity, viscoplasticity and the thermal effect. The results predicted by current model are in good agreement with the experimental data, which allows us to implement the model into FEA for future structural analysis.
He, Ge, Liu, Yucheng
Effects of As-Cast Surface Conditions and Local Geometry on Plating Deposition2018-01-504511/14/2018
The inhomogeneity of casting microstructure can present many challenges to subsequent processing of castings such as electroplating. Specifically the surface microstructure and local topographic features have significant impact on the electroplating deposition thus the continuity of the plating films. The authors attempt to categorize the common casting surface microstructure features and correlate them to the electroplating characteristics such as conductivity and current density distribution, which in turn affect the plating deposition. Forming mechanisms of some of the most common casting surface microstructures that affect electroplating are discussed. Desirable casting surface microstructure for electroplating and the casting design and process practices to achieve it are proposed.
Huang, Yanjun, Ohta, Makoto, Pederson, Tara, Milligan, Orit (Baron)
COVER – ENGINE ACCESSORY DRIVE, SQUARE, 5.000 BOLT CIRCLE, AMS4490 (UNS M11910)AS3222D (Current)10/18/2018
E-25 General Standards for Aerospace and Propulsion Systems
COVER - ENGINE ACCESSORY DRIVE, SQUARE, 127.28 BC, METRIC AMS4424 (UNS M11630) OR AMS4484MA3454B (Current)9/17/2018
E-25 General Standards for Aerospace and Propulsion Systems
COVER – ENGINE ACCESSORY DRIVE, SQUARE, 2.653 BOLT CIRCLE, AMS4490 (UNS M11910)AS3221C (Current)7/16/2018
E-25 General Standards for Aerospace and Propulsion Systems
COVER - ENGINE ACCESSORY DRIVE, ROUND, 5.000 BOLT CIRCLE, AMS4490 (UNS M11910)AS3223C (Current)7/16/2018
E-25 General Standards for Aerospace and Propulsion Systems
COVER - ENGINE ACCESSORY DRIVE, ROUND, 8.000 BOLT CIRCLE, AMS4490 (UNS M11910)AS3224C (Current)6/20/2018
E-25 General Standards for Aerospace and Propulsion Systems
COVER - TYPE XVI, XVII-C, D, E, AND F ENGINE ACCESSORY DRIVEAS3542A (Current)6/20/2018
E-25 General Standards for Aerospace and Propulsion Systems
Implementing Advanced Technologies in the Sand Casting Supply ChainF-0074-2018-128065/14/2018
ABSTRACT How many castings should be poured before getting a useable part? The ideal answer may be one, but the reality is that the ideal is infrequently realized. What alloy is the part? What is its size? What is the complexity? How is the part complex: many interior cores, many thick to thin section transitions, very thin walls, or something else entirely? No two part geometries will be exactly the same, so the challenges and expectations for each part will be different. At Sikorsky, our sand cast components only seem to be getting more complex, with more demanding dimensional and metallurgical requirements. All of these factors makes the casting of these parts more challenging. This also coincides with a time where lead times and costs to develop a new casting are being scrutinized.
Woodworth, Heather, Jr., William
Cover - Engine Accessory Drive, Round, 10.000 Bolt Circle, AMS4490 (UNS M11910)AS3225D (Current)4/28/2018
E-25 General Standards for Aerospace and Propulsion Systems
An Integrated Approach to Constitutive Modeling and Life Prediction for Automotive Materials2018-01-12134/3/2018
An integrated approach of constitutive modeling and life prediction is presented through introduction of the integrated creep-fatigue theory (ICFT). The ICFT is formulated based on participating deformation and damage mechanisms, which not only describes the cyclic deformation behavior but also the life and fracture mode. Automotive exhaust system materials such as ductile cast iron and austenitic cast steel are used as example materials for demonstration in good agreement with experimental results and metallurgical examinations. This enlightens the understanding of the roles each mechanism plays in low-cycle fatigue (LCF) and thermomechanical (TMF) processes, thus helping material and component design specifically targeting the most damaging mechanism(s) encountered in service.
Wu, Xijia
Advances in Gasoline Direct Injection Fuel Pump Technologies2018-01-03674/3/2018
The introduction of gasoline direct injection (GDI) fuel systems has created numerous technical and manufacturing challenges for fuel system engineers. Direct injection systems run at significantly higher pressures compared to port fuel injection, leading to increased stresses on fuel system components. The demands of GDI pump applications have led to significant innovation opportunities in areas such as high-pressure sealing, control of pumping noise and management of increased loads on pumping elements and pump structure. Shifts in the methodologies for the design of components and materials used, as well as changes to the validation and manufacturing processes, have been required to develop fuel systems for direct injection engines. New technologies for the assembly and joining of materials have also been important to further optimize designs for size, weight, and cost. Recent advances in materials and forming technologies have opened design possibilities to integrate pump sub-systems for improved function and packaging. Of these technologies, laser welding, metal injection molding, and precision stamping are key aids in creating robust, cost-effective and low-weight solutions. Additionally, the control of debris generation and migration during all stages of the value stream is a critical enabler of pump performance consistency and quality. Part transport, handling and cleaning, audit and analysis considerations must be fully integrated into process layout and material flows to achieve target requirements. Control of environmental air quality and airborne aerosols also plays a critical role in assembly quality. In this paper, design strategies, production methodologies and key lessons learned are reviewed for current and upcoming Stanadyne GDI pump technology.
Cavanagh, Mark, Pellini, Richard, Pinson, John
Development of Aluminum Suspension Part using by High Pressure Casting of Electro-Magnetic Stirring2018-01-13944/3/2018
The weight reduction of the car suspension parts has a direct influence on the ride and handling. However, the application of nonferrous metal materials, such as aluminum and magnesium, which results in a lighter weight of the suspension can lead to an increase in manufacturing costs compared to cast iron. In this study, vertical type high-pressure die casting using by electro-magnetic stirring (EMS) with A356 alloy in the sleeve was used to control the fine microstructure. Process optimization and part development, as well as unit product and automotive assessment were carried out for electro-magnetic stirring methods. Without making the slurry, the mechanical properties were obtained through optimization of process variables UTS 320MPa, YS 239MPa, EL 13.3%. It also succeeded in mass production with minimum cost increase of aluminum suspension components.
Kim, Minsoo, Kim, Youngchan, Lee, Junmin, Yoon, KwangMin, YounLae, Cho
Fracture Characteristic Prediction of High-Strength Aluminum Alloy Extrusion using Cockcroft-Latham Ductile Fracture Criteria2018-01-01094/3/2018
Demands are increasing for the reduction of vehicle weight to enhance automobile fuel efficiency and driving performance, with the use of aluminum alloys expected to help. High-strength aluminum alloys (6xxx series, 7xxx series) are called for to enhance crash safety performance, and the prediction of material fracture is a key factor in the application of these alloys. This research presents a FEM model that can predict both tensile fracture and bending fracture when large deformations occur in the extrusion direction of high-strength aluminum alloy extrusion. The fracture characteristics of high-strength aluminum alloy extrusion were obtained by tensile and bending tests, and the factors governing ductile performance were clarified. Fracture was defined in the FEM model using the Cockcroft-Latham ductile fracture model. In addition, the surface crystal grain of aluminum extrusion becomes coarse as a result of the extrusion process, and the hardness distribution also exhibits a soft surface layer. Therefore, a definition that varies the material properties in the plate thickness direction, using the definition of laminate material as the composite material, was added to the FEM modeling process. FEM structural analysis was performed with tensile and bending tests using these definitions, and the analysis accuracy was verified. The results showed that the FEM structural analysis of tensile and bending tests reproduced the experimental results for load and stroke fractures to within an error of 10%. In order to describe tensile fracture and bending fracture in the direction of high-strength aluminum alloy extrusion using FEM, the Cockcroft-Latham ductile fracture model was combined with a method of varying the material properties in the plate thickness direction, according to the definition of laminate material. This enabled an accurate fracture load and stroke prediction within an error of 10%.
Sugimoto, Nao, Takaki, Naoki, Takada, Kenji
TOOL, CONNECTOR ASSEMBLY, FOR MIL-C-5015 CONNECTORSAS34801A (Current)1/18/2018
AE-8C2 Terminating Devices and Tooling Committee
Zinc Alloy Ingot and Die Casting CompositionsJ468_201801 (Current)1/9/2018
SIMILAR SPECIFICATIONS—UNS Z33521, former SAE 903, ingot is similar to ASTM B 240-79, Alloy AG40A; and UNS Z33520, former SAE 903, die casting is similar to ASTM B 86-76, Alloy AG40A. UNS Z35530, former SAE 925, ingot is similar to ASTM B 240-79, Alloy AC41A; and UNS Z35531, former SAE 925, die casting is similar to ASTM B 86-82a, Alloy AC41A.
Metals Technical Committee
Identification CastingsAMS2804D (Current)10/12/2017
This specification covers the requirements for identification of castings.
AMS B Finishes Processes and Fluids Committee
Application of Six Sigma Methodology to Improve Product Quality in Injection Molded Parts at Supplier End in Motorcycle Industry2017-01-50119/29/2017
Process Parameters play a vital role in product quality of Injection Molded components. Variation in process parameters will lead to Injection Molded manufacturing defects like Sink Mark, Flow Mark, Silver Streak, Flash, Warping, Weld lines, Jetting, voids, Short Shot & Bubbles. This manuscript is innovative because suppliers (Tier 1 and Tier 2) do not use DoE for standardization of their process parameters in Injection Molding and High Pressure Die Casting. They do trial and error method to arrive at the process parameters which is error prone and time consuming. The variation of process parameters can be optimized using Six Sigma approach, a structured methodology which is Process focused & data driven approach. The purpose of this paper is to present through a case study how the concepts of Design of Experiments, which is a part of Six Sigma Methodology can be used for improving the Injection Molding Process at supplier end reducing defects & hence improving Quality at supplier which stops 100% BOP inspection and segregation when the parts reach the OEM. Here one of the products in Motorcycle Industry has been taken which has 100% Sink Mark defect & resulting in 100% rework. By following the six sigma DMAIC approach and using tools like SIPOC, PMAP, Fish Bone Diagram, Cause and Effect Matrix & Design of experiments to optimize the process parameters at supplier Injection Molding Machine through cross functional team approach. The result has proved that the quality of the product in automotive Industry can be improved by using Six Sigma Approach. This approach can be used for all suppliers and all OEMs or can be horizontally deployed in the Injection Molding Process and High Pressure Die Casting Process to reduce defects and improve product quality by reducing process variation.
Shankaranarayana, Raviprakash
Fatigue Assessment of Nodular Cast Iron with Material Imperfections2017-01-03443/28/2017
For the design of thick-walled nodular cast iron components, fatigue assessment, especially in the context of local imperfections in the material, is a challenging task. Not only the cyclic material behavior of the sound baseline material, but also the cyclic behavior of materials with imperfections, such as shrinkages, dross and chunky graphite, needs to be considered during the design process of cast iron components. In addition to this, new materials, such as solid solution strengthened alloys, offer new possibilities in lightweight design, but need to be assessed concerning their fatigue strength and elastic-plastic material behavior. If a safe and reproducible fatigue assessment for any component cannot be performed and a secure usage is therefore not given, the cast components are generally rejected, leading to a loss of additional material, energy and money for recasting the component. In this context, four nodular cast iron materials are compared with reference to their cyclic material and fatigue behavior as well as their potential for a lightweight design, based on stress- and strain-controlled tests both for sound and defective material. However, to develop an optimal and individual fatigue design method for cast components with local material imperfections present, the component’s local fatigue strength needs to be combined with information from non-destructive testing (NDT), since a removal of specimens is generally not possible. For this purpose, as an example, a method is described that uses information from ultrasonic and X-ray analysis as well as the given fatigue strength of the baseline material to conduct a fatigue assessment of local shrinkages in nodular cast iron components. The method is based on the reproducible measurement of the local density by NDT and its correlation with the local fatigue notch factor, enabling a safe and local assessment of the allowable fatigue strength when shrinkages are present.
Bleicher, Christoph, wagener, Rainer, Kaufmann, Heinz, Melz, Tobias
A Segregated Thermal Analysis Method for Liquid-Cooled Traction Batteries2017-01-06293/28/2017
Thermal modeling of liquid-cooled vehicle traction battery assemblies using Computational Fluid Dynamics (CFD) usually involves large models to accurately resolve small cooling channel details, and intensive computation to simulate drive-cycle transient solutions. This paper proposes a segregated method to divide the system into three parts: the cells, the cold plate and the interface between them. Each of the three parts can be separated and thermally characterized and then combined to predict the overall system thermal behavior for both steady-state and transient operating conditions. The method largely simplifies battery thermal analysis to overcome the limitations of using large 3D CFD models especially for pack level dynamic drive cycle simulations.
Kuo, John, Garfinkel, George
Crack Failure Mode Analysis for Cam-Housing Rocker Arm and Pin2017-01-03583/28/2017
During the extensive testing under NATO and Commercial Standards, crack is observed in camshaft housing to initiate from the eccentric shaft bore and go toward the hold down bolt hole. Hence lab test proposal is originated to induce similar failure in a controlled method and then to compare new design alternatives. CAE analysis follows the same set up as the lab test to duplicate failure mode in stress analysis and fatigue analysis with duty cycle loads, and then figures out two strategies on how to improve the design, including geometry change and material change. In geometry wise, four new design iterations are evaluated for comparison. In material wise, one new material for camshaft housing and five manufacturing effect parameters for pin and rocker arm are compared, including ground, machined, machined and decarburization, casting, as well as casting and nitride. With those comparisons, all manufacturing parameters are compared based on effectiveness to affect the fatigue life. Besides design change, manufacturing cost is also prone to be a relatively critical factor. By all means above, the new architecture is decided and successfully validated by the following testing and can meet production criteria as well. The CAE software applied in the analyses are Abaqus for stress analysis and nCode DesignLife for fatigue analysis.
Song, G
Vote for Tech Briefs 22nd Annual Readers' Choice AwardsTBMG-2607112/1/2016
Each December, we ask our readers to cast their vote for the annual NASA Tech Briefs’ Readers’ Choice Product of the Year Awards. Each month, our editors choose a Product of the Month that has exceptional technical merit and practical value for our design engineering readers.
Push-On Spring Nuts Metric Series - General SpecificationsJ892M_201611 (Current)11/21/2016
Included herein are general, dimensional, and performance specifications for those types, styles, and sizes of steel stamped Push-On Spring Nuts recognized as SAE standard. These nuts are intended for general use where the engagement on the mating metal or plastic studs and in some cases screw bolt threads is considered adequate for the fastening joint application. It should be noted that Push-On Spring Nuts having other characteristics and configurations are available and manufacturers should be consulted. For the inch equivalent of this document, see SAE J892.
Fasteners Committee
Application of Rapid Heat and Cool Molding to High Strength Outer Parts without Painting Treatment2016-32-002411/8/2016
Glass fiber reinforced plastic of polyamide is applied as one of the materials used for the high strength exterior parts of a motorcycle, such as a rear grab rail or a carrier, to which both strength and good exterior appearance are required. However, Glass Fiber reinforced Polypropylene (PPGF), which is relatively inexpensive material, has a property that the contained glass fibers are prone to be exposed at the surface and, therefore, the requirements for good appearance are hardly met by using PPGF. In this study, Heat and Cool molding method (H&C molding) was employed to realize a cost reduction by using PPGF yet without applying painting process, and the established method was applied to mass production while fulfilling the requirements for a good exterior appearance. In H&C molding, the metal molds are heated up by steam and cooled down by water after molding. This process works for making superior surface appearances and the appearance quality is determined by the temperature control of the molds. H&C molding has been generally applied to the parts with a flat shape and straight piping with a diameter of around 10 mm is arranged close to the surface of a metal mold cavity to get a good efficiency of temperature control. However, when this method is applied to a motorcycle part that is structured by three dimensional surfaces, these conventional piping arrangements cannot satisfy the requirements for a short molding cycle time and an even distribution of mold surface temperatures at the same time. In our study, a piping arrangement design by which the pipes are located along the three dimensional cavity surfaces was investigated. The piping arrangement design was determined based on the measurement results on test pieces and the molding cycle time of 100 seconds was eventually achieved. Furthermore, a proof testing to examine the material strength and the weather resistances is conducted as well.
Sugio, Daisuke, Okazaki, Shinpei, Kaneko, Mitsuo
High Performance Aluminum Casting Alloys for Engine Applications2016-32-001911/8/2016
In the early 1980's, some promising research and development efforts focused on powder metallurgy revealed that aluminum alloys containing 4 wt% cerium exhibit high temperature mechanical properties exceeding those of the best commercial aluminum casting alloys currently in production. Cerium oxide is an abundant rare earth oxide that is often discarded during the refining of more valuable rare earths such as Nd and Dy. Therefore, the economics are compelling for cerium as an alloy additive. In this paper, we report select results obtained during an investigation of the castability of aluminum-cerium alloys and determine compositional modifications that may be required to ensure the compatibility of the alloy with near net shape casting methods such as advanced sand casting, die casting, permanent mold casting and squeeze casting. Al-Ce alloys were cast in binary composition of 6-16 wt% Ce. Commercially pure aluminum ingots were melted and held at approximately 785°C. Ternary and quaternary alloys with Si and Mg additions were also investigated. Test bars were cast to establish mechanical properties and step plates and hot tear molds were used to determine sensitivity to solidification conditions and hot tearing sensitivity respectively. Finally, air cooled engine cylinder heads were cast in sand molds to get a sense of castability in complicated shape castings.
Weiss, David
Powder Reuse and Its Effects on Laser Based Powder Fusion Additive Manufactured Alloy 7182016-01-20719/20/2016
Laser Based Powder Bed Fusion, a specific application of additive manufacturing, has shown promise to replace traditionally fabricated components, including castings and wrought products (and multiple-piece assemblies thereof). In this process, powder is applied, layer by layer, to a build plate, and each layer is fused by a laser to the layers below. Depending on the component, it appears that only 3-5% of the powder charged into the powder bed fusion machine is fused. Honeywell’s initial part qualification efforts have prohibited the reuse of powder. Any unfused powder that exits the dispenser (i.e., surrounds the build or is captured in the overflow) is considered used. In order for the process to be broadly applicable in an economical manner, a methodology should be developed to render the balance of the powder (up to 97% of the initial charge weight) as re-usable. Though multiple manufacturers may be re-using powder, there is no industry standard methodology or practice for powder re-use. The present study (with 10 uses of the same powder lot) shows no appreciable impact on nickel-base superalloy 718 chemistry, powder size / distribution, or mechanical properties, with exception of gradual increase in oxygen content of the powder.
Hann, Brian A.
Interactive Effects of Thermal Deformation and Wear on Lateral Runout and Thickness Variation of Brake Disc Rotors2016-01-19399/18/2016
Brake judder is one of the most serious problems in automotive-brake systems. It is basically a forced vibration caused by the friction-surface geometry of a brake disc, and therefore, disc rotors play a significant role in judder. There are two types of judder: cold and hot. Hot judder is caused by the thermo-mechanical deformation of a brake disc due to high-speed braking. There are several shapes of deformation, e.g., coning and circumferential waviness. Circumferential waviness is caused by thermo-mechanical buckling and typically found as a butterfly shape in a 2nd rotational-order and hot-spotting. In a previous paper, two groups of disc castings with different material homogeneity were machined intentionally to have two kinds of dimensional variations. From repetitive high-speed braking tests of these discs, both the material and dimensional homogeneity were found to affect the wave-like deformation of discs in the 1st and 2nd rotational-orders with different significance between the two casting groups. There are many mechanisms affecting disc geometry during braking. Plastic deformation and wear cause permanent effects, while thermal expansion and elastic deformation are reversible. A disc’s initial shape before braking affects its geometry both transiently and permanently. Considering these effects, the previous test results were reanalyzed in the present paper. Some discs exhibited large transient runout and DTV but small permanent DTV, while others behaved differently. The thermal deformation and differential wear were confirmed to interactively affect the transient and permanent geometry of operating brake discs.
Okamura, Toshikazu
Development of Aluminum Composite Automotive Brake Rotors2016-01-19379/18/2016
Aluminum metal matrix composite brake rotors with a selective ceramic function reinforcement gradient (FRG) have been developed for automotive applications. This paper will highlight the design, manufacturing, and testing of the rotors. Weight saving of an aluminum composite rotor in comparison to an industry standard cast iron rotor is 50-60%. With this material change comes design considerations to manage rotor temperature, rotor surface integrity, and friction. Manufacturing methods to meet these design constraints were needed to develop a viable high performance aluminum composite rotor. High pressure squeeze casting with soluble coring techniques were developed to incorporate the selective FRG MMC rotors. Dynamometer testing was performed, concentrating on brake friction and temperature to evaluate the macro and micro interfaces in the rotors. The rotors’ testing results indicate that a functional reinforced aluminum metal matrix composite rotor is viable option for front and rear brake applications in the automotive and commercial trucking market.
Erva, Taylor, Loukus, Adam, Luskin, Luke
Application of Casting Technologies to Sikorsky Development ProgramsF-0072-2016-114885/17/2016
Sikorsky Aircraft Corporation recently demonstrated new casting technologies in two if its latest development programs, the S-97 RAIDER™ aircraft and Future Advanced Rotorcraft Drive System (FARDS), to improve casting quality and speed to market. The development of new sand castings for rotorcraft gearbox housings can frequently take years to complete. Using modeling and simulation, additive manufacturing of the mold, and low pressure casting, Sikorsky has shown that the lead time and number of pours to yield a usable casting has been reduced by at least ten times compared to using traditional casting methods. These technologies also reduce the amount of weld repair required. Ultimately this will allow for new and improved gearbox designs with better speed to the market.
Woodworth, Heather, Fetty, Jason, Baker, Treven
Development of Aluminium Hollow Subframe Using High-Pressure Die Casting2016-01-04064/5/2016
High-tensile steel plates and lightweight aluminum are being employed as materials in order to achieve weight savings in automotive subframe. Closed-section structures are also in general use today in order to efficiently increase parts stiffness in comparison to open sections. Aluminum hollow-cast subframe have also been brought into practical use. Hollow-cast subframe are manufactured using sand cores in gravity die casting (GDC) or low-pressure die casting (LPDC) processes. Using these manufacturing methods, it is difficult to reduce product thickness, and the limitations of the methods therefore make the achievement of weight reductions a challenge. The research discussed in this paper developed a lightweight, hollow subframe technology employing high-pressure die casting (HPDC), a method well-suited to reducing wall thickness, as the manufacturing method. Hollow-casting using HPDC was developed as a method of forming water jackets for water-cooled automotive engines. Because the volume of the sand cores used in the method is low despite the complexity of their shape, the hollow-casting of large parts such as subframe necessitated the molding of larger sand cores than are conventionally employed. In addition, it was necessary to develop a sand core baking technology that produced a good strength balance, making it possible for the cores to resist casting pressures but collapse easily in the sand removal process following casting. A sand core technology balancing pressure resistance with collapsibility, which had previously represented an issue, was developed in order to make it possible to hollow-cast large parts, and a non-heat-treated Al-Mg-Si alloy was employed in order to reduce costs. The developed hollow aluminum subframe is approximately 40% lighter than a conventional subframe manufactured from welded steel plates (Fig. 1).
Asami, Akihiko, Imanishi, Tomoyuki, Okazaki, Yukio, Ono, Tomohiro, Tetsuka, Kenichi
Track Bar Bracket Development with the Help of Advanced Optimization Techniques2016-01-13874/5/2016
The advanced Optimization techniques help us in exploring the light weight architecture. This paper explains the process of designing a lightweight track bar bracket, which satisfies all durability performance targets. The mounting locations and load paths are critical factors that define the performance and help in the development of weight efficient structure. The process is to identify the appropriate bolt location through Design of Experiment (DOE) and topology based studies; followed by section and shape optimization that help to distribute material in a weight efficient manner across the structure. Load path study using topology optimization is performed to identify the load path for durability load cases. Further shape optimization is done using hyper study to determine the exact thickness of the webs and ribs. A significant weight reduction from the baseline structure is observed. This process may be applicable for all casting components.
Sudalaimuthu, Subash, Lin, Barry (Baizhong), Sithik, Mohamed, Rajendran, Rajeev Sakunthala
Predicting Stress vs. Strain Behaviors of Thin-Walled High Pressure Die Cast Magnesium Alloy with Actual Pore Distribution2016-01-02904/5/2016
In this paper, a three-dimensional (3D) microstructure-based finite element modeling method (i.e., extrinsic modeling method) is developed, which can be used in examining the effects of porosity on the ductility/fracture of Mg castings. For this purpose, AM60 Mg tensile samples were generated under high-pressure die-casting in a specially-designed mold. Before the tensile test, the samples were CT-scanned to obtain the pore distributions within the samples. 3D microstructure-based finite element models were then developed based on the obtained actual pore distributions of the gauge area. The input properties for the matrix material were determined by fitting the simulation result to the experimental result of a selected sample, and then used for all the other samples’ simulation. The results show that the ductility and fracture locations predicted from simulations agree well with the experimental results. This indicates that the developed 3D extrinsic modeling method may be used to examine the influence of various aspects of pore sizes/distributions as well as intrinsic properties (i.e., matrix properties) on the ductility/fracture of Mg castings.
Choi, Kyoo Sil, Barker, Erin, Cheng, Guang, Sun, Xin, Forsmark, Joy, Li, Mei
Fabrication of an Integrated Photonic Waveguide Joint in Micromachined SiliconTBMG-242554/1/2016
High-aspect-ratio silicon structures are necessary components in many MEMS (microelectromechanical systems). Aspect ratio is defined as the ratio of the height of the structure to its lateral width. The structures are typically fabricated through bulk micromachining steps such as deep reactive ion etching. In some cases, multiple levels of high-aspect-ratio structures are required. For instance, one may want to etch completely through a silicon wafer to thermally isolate a bolometer or provide waveguide coupling to an antenna defined on an insulating membrane, and at the same time have integrated high-topology structures required for microwave coupling or filtering. Definition of the structures typically uses photolithographic technology. But for high-aspect-ratio structures, spin cast resist becomes difficult to incorporate due to the non-uniform thickness of the resist around tall structures. One can cast very thick layers of photoresist, but this limits the minimum feature size, and additionally, very thick layers of photoresist are difficult to work with due to solvent release and moisture that can cause the resist to crack or swell. For electromagnetic reasons, the structures would preferably be made from conductive material such as metal or degeneratively doped silicon. The objective of this work was to incorporate multiple levels of conductive high-aspectratio structures with standard micromachining processes.
Surface Generation speeds composites throughput with one-shot stamp-forming process16AUTP02_072/1/2016
Surface Generation is working with research group WMG, an academic department of the University of Warwick, and AGC AeroComposites to develop new composite press-forming processes for automotive and aerospace manufacturers. Surface Generation, a U.K.-based provider of advanced carbon-fiber processing technologies, is developing new press-forming mold faces that incorporate its patented PtFS (Production to Functional Specifications) technology for the production of high-performance thermoplastic composite components. By integrating Surface Generation's active thermal management technologies into the mold face itself, WMG and AGC are able to continuously adapt heating and cooling levels for each mold area and process stage in real time. The companies believe that this enhanced capability will improve both the quality and throughput of compression molding applications.
Gehm, Ryan
Surface Generation speeds composites throughput with one-shot stamp-forming process16OFHP02_062/1/2016
Surface Generation is working with research group WMG, an academic department of the University of Warwick, and AGC AeroComposites to develop new composite press-forming processes for automotive and aerospace manufacturers. Surface Generation, a U.K.-based provider of advanced carbon-fiber processing technologies, is developing new press-forming mold faces that incorporate its patented PtFS (Production to Functional Specifications) technology for the production of high-performance thermoplastic composite components. By integrating Surface Generation's active thermal management technologies into the mold face itself, WMG and AGC are able to continuously adapt heating and cooling levels for each mold area and process stage in real time. The companies believe that this enhanced capability will improve both the quality and throughput of compression molding applications.
Gehm, Ryan
AS2989 Locking Screw – Die CastingAS2989-3 (Current)12/4/2015
No scope available.
Engine and Airframe Technical Standards Committee (TSC)
AGS511 Ballast Weights. (Grey Cast Iron)AGS511-2 (Current)12/3/2015
No scope available.
Engine and Airframe Technical Standards Committee (TSC)
Vote for Tech Briefs' 21st Annual Readers' Choice AwardsTBMG-2354812/1/2015
Each December, we ask our readers to cast their vote for the annual NASA Tech Briefs Readers’ Choice Product of the Year Awards. Each month, our editors choose a Product of the Month that has exceptional technical merit and practical value for our design engineering readers.
Effect of Material and Dimensional Homogeneity on Thermo-mechanical Deformation of Brake Discs during High-speed Braking2015-01-26739/27/2015
Brake judder is one of the most serious problems in automotive-brake systems, and brake discs play a significant role in judder. There are two types of brake judder: cold and hot. Hot judder is caused by the thermo-mechanical deformation of a disc rotor due to high-speed braking. There are several causes and shapes of the deformation, e.g., coning and circumferential waviness. Circumferential waviness of brake discs is typically found as a butterfly shape in a 2nd rotational-order and corrugation (or hot-spotting) around a 10th order, which are caused by thermo-mechanical buckling. The author focused on the effects of material and dimensional homogeneity on the transient and permanent wave-like deformation of ventilated discs in low rotational-orders during repetitive high-speed braking. The tested discs were in two groups that had the same design and gray-cast-iron class but were cast in two foundries by using horizontal- and vertical-molding machines, respectively. Consequently the two groups of disc castings differed in the circumferential homogeneity of material. These discs were machined intentionally to have two kinds of dimensional variations in four rectangular orientations on the basis of the gating locations of each casting group. The temperature and deformation of disc rotors on the same radius were measured simultaneously during braking at a constant speed and torque. Measured deformation shapes were analyzed through fast Fourier analyses. As a result, both material and dimensional homogeneity were found to affect a disc's wave-like deformation in the 1st and 2nd rotational-orders with different significance between the two casting groups.
Okamura, Toshikazu
Low-Pressure Casting of Bulk Metallic Glasses for Gears and Other ApplicationsTBMG-224057/1/2015
With the correct selection of composition, some bulk metallic glasses (BMGs) have been demonstrated that have excellent combinations of hardness, fracture toughness, and wear resistance so that their use in gears and gearboxes is a potentially commercially viable application. For BMGs to be used as a low-cost alternative to steel gears, rapid fabrication strategies are needed to cast the BMGs into net-shaped gears that require little or no post-casting machining prior to use. Die casting, suction casting, and other cold-mold casting techniques have been widely demonstrated for BMGs in the past, but the unique nature of gears precludes traditional techniques from being used in an optimal way.
Items per page:
1 – 50 of 669