Browse Topic: Rare earth metals

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Risk Mitigation for Pb-Free Solders Used Internally to PartsARP6537 (Current)10/19/2020
This document provides risk mitigation for Pb-free solders used internal to parts used in Aerospace and Defense applications. It will include mitigations applicable to encapsulated and cavity devices as the needs arise in industry. Currently this revision only addresses devices with encapsulation or underfill. Mitigations for open cavity devices are still being discussed, and will be addressed in future revisions. Microbumps with Thermal Compression Bonding (TCB) are not addressed by the mitigations in this document. The use of Pb-free microbumps with TCB are considered out of scope at this time. It is expected that this document will be primarily used by Control Levels 3 and 2C (as defined in GEIA-STD-0005-2 for programs that do not allow use of Pb-free tin or only allow its use on an exception basis). It may be used by other levels, or by applications not using GEIA-STD-0005-2.
G-24 Pb-free Risk Management Committee for ADHP
The Benefits of Tungsten CableTBMG-362423/1/2020
There is no one-size-fits-all material when producing mechanical cable. The material chosen to produce wire rope can vary from one application to the next, because commonly, no two applications place the same demands on the stranded cable. Consider tungsten, for instance. Also known as Wolfram (W, atomic number 74), tungsten possesses the highest melting temperature of all metals. For this reason, this rare earth metal is commonly found in light bulb filaments, x-ray tubes, and arc-welding electrodes. Because of such unique mechanical properties, tungsten has become an integral component in the manufacturing of many of today’s cutting-edge medical devices, including surgical robots.
Going Beyond the Basics: Innovative Step Motor Designs Give Machine Designers More Options for Motion ControlTBMG-360022/1/2020
Machine and system designers now have greater options in choosing a motor to meet motion control requirements. While basic step motors with open-loop control schemes abound in the marketplace, different motor and drive designs offer interesting solutions for smarter, faster, quieter operations with more torque. Some incorporate smart drives for higher-level streaming commands or onboard motion control, while others add encoders for greater torque and accuracy. These options can offer better solutions as applications become more sophisticated and demanding, while companies address initiatives for greener operations. This article outlines different step motor options available on the market and considerations for their use.
Titanium Alloy, Round Bar and Wire 3Al - 8V - 6Cr - 4Mo - 4Zr Consumable Electrode Melted Solution Heat Treated and Cold DrawnAMS4957G (Current)1/14/2020
This specification covers a titanium alloy in the form of round bar and wire, 0.625 inch (15.88 mm) and under in nominal diameter or thickness.
AMS G Titanium and Refractory Metals Committee
Recovery of Mercury and Rare Earth Elements from Fluorescent Lamp PhosphorsTBMG-358031/1/2020
All fluorescent lights contain small amounts of mercury and rare earth metals. There is a need to safely remove and recycle mercury and rare earth elements from used fluorescent lamps in order to keep the valuable and potentially poisonous metals out of the environment and aid the domestic recovery of critical materials.
National Energy Technology LaboratoryTBMG-349278/1/2019
The National Energy Technology Laboratory (NETL) is a U.S. Department of Energy (DOE) national laboratory — with sites in Anchorage, AK; Albany, OR; Morgantown, WV; and Pittsburgh, PA — that produces technological solutions to America's energy challenges. For more than 100 years, NETL — and its predecessor facilities — has advanced technology to provide clean, reliable, and affordable energy to the American people.
Shear Assisted Processing and ExtrusionTBMG-347547/1/2019
Shear Assisted Processing and Extrusion (ShAPE™) allows creation of wire, bar, and tubular extrusions that show significant improvement in material properties; for example, magnesium extrusions have been manufactured with unprecedented ductility (how far the material can stretch before it breaks) and energy absorption (how much energy can be absorbed during compression of a tubular extrusion) over conventional methods.
Rotary Electrical ContactTBMG-346206/1/2019
Researchers have developed a fundamentally new type of rotary electrical contact that addresses the two limitations of conventional brush/slip ring technology: 1) short operating lifetime due to sliding-contact wear, and 2) electrical arcing associated with contact bounce.
Chemical Check Analysis Limits Titanium and Titanium AlloysAMS2249J (Current)4/5/2019
This specification defines limits of variation for determining acceptability of the composition of cast or wrought titanium and titanium alloy parts and material acquired from a producer.
AMS G Titanium and Refractory Metals Committee
Failsafe Linear Magnetic BrakesTBMG-341134/1/2019
Linear permanent magnet brakes, also known as eddy current brakes, are a failsafe, power-free deceleration system that is used in conjunction with a metal reaction plate. Ceramic or rare earth magnets are bonded to a steel back iron plate; no input power is required.
Facility Focus: Ames LaboratoryTBMG-3340812/1/2018
Ames Laboratory is a government-owned, contractor-operated national laboratory of the U.S. Department of Energy (DOE), operated by and located on the campus of Iowa State University in Ames, IA. For more than 70 years, Ames Laboratory has successfully partnered with Iowa State University and is unique among the DOE laboratories in that it is physically located on the campus of a major research university.
2018 Create the Future Design Contest: Automotive/Transportation Category WinnerTBMG-3331911/1/2018
Toward Material Efficient Vehicles: Ecodesign Recommendations Based on Metal Sustainability Assessments05-11-03-00219/17/2018
Current End-of-Life Vehicle (ELV) recycling processes are mainly based on mechanical separation techniques. These methods are designed to recycle those metals with the highest contribution in the vehicle weight such as steel, aluminum, and copper. However, a conventional vehicle uses around 50 different types of metals, some of them considered critical by the European Commission. The lack of specific recycling processes makes that these metals become downcycled in steel or aluminum or, in the worst case, end in landfills. With the aim to define several ecodesign recommendations from a raw material point of view, it is proposed to apply a thermodynamic methodology based on exergy analysis. This methodology uses an indicator called thermodynamic rarity to assess metal sustainability. It takes into account the quality of mineral commodities used in a vehicle as a function of their relative abundance in Nature and the energy intensity required to extract and process them. This method is proposed as a tool to identify the most critical components in a vehicle so as to define specific ecodesign recommendations for them. The methodology is applied to a SEAT Leon 2.0 Diesel III model (segment C). Main recommendations are focused on reducing the use of metals with high thermodynamic rarity values such as Ag, Au, Cu, Ga, In, Pd, Pt, Sn, Ta, and Te. These metals are mainly used in electrical and electronic equipment. It is also recommended to reduce the disassembly time of a number of critical components such as airbag unit, electronic control unit, lighting switcher, antenna amplifiers, panel instrument, sensors, infotainment unit, light-emitting diodes (LEDs), and motors. A fast and easy disassembly would allow in subsequent phases to apply specific recycling processes based on mechanical and hydrometallurgical hybrid approaches instead of only mechanical separation techniques.
Ortego, Abel, Valero, Alicia
Sustainability and Production Economics of Titanium for Engine Valve: India Perspective2018-28-00027/9/2018
Automotive industry is looking to have breakthrough for utilization of titanium in vehicles with cost effective solution. This is due to the relative cost factor and for titanium it is 20 and 2.9 times greater than steel and aluminium respectively. Looking at Today’s scenario of multi material vehicle, it weighs approximately 221 kg on usage of conventional materials i.e. aluminium 37%, steel 42% and composites 21%. also Indian government has taken bold decision to meet BS VI norms directly by 2020 and to achieve the same it is required to meet NOx level of 0.06 g/km for gasoline vehicles and 0.080 g/km for diesel vehicle along with EGR rates of 35% at full load at which conventional materials like steel, aluminium has to withstand for high temperature cycles and high compressed air pressure at outlet. Hence positive progress of implementation of titanium by proving its production economy and sustainability for leading automotive components like exhaust system, valve train and turbocharger components in vehicles for the mass market is prime important. But focusing on mass market may not work effectively as total production of titanium i.e. ilmenite and rutile is about 522 thousand tonnes by 2016 and on the other hand vehicle production in India by 2016 was 24.015 million units. Considering usage of titanium in other sectors, titanium if contribute up to 2 kg /vehicle (48 thousand tonnes) may leads to proportionate increase in fuel economy, decrease in emission and increased titanium usage in vehicle by 9.2%. To do so automotive engineers, designers need to attack cost, manufacturing challenges and effective research and development on titanium ore extraction technology to make highly priced titanium user friendly for automotive industry. Detail discussion on addressed issues of titanium are discussed in this paper and to prove sustainability of titanium for automotive application metallurgical failure analysis of failed valve (inlet & exhaust) is carried out using spectroscopy, optical microscopy and scanning electron microscopy which clearly indicates need of titanium family for high temperature automotive components.
Garud, Vikrant, Bhoite, Sanjiwan, Patil, Sagar, Ghadage, Suraj, Rawandale, Shitalkumar
Ferroelectric Material Improves UltrasoundTBMG-289455/1/2018
Development of a theoretical basis for ultrahigh piezoelectricity in ferroelectric materials has led to a new material with twice the piezo response of any existing commercial ferroelectric ceramics.
Pros & Cons of Advanced Lightweighting MaterialsTBMG-285493/1/2018
Although cars have been around for more than a century, the material they are made of (steel) has mostly stayed the same. It has only been in the past few decades that advanced materials ranging from aluminum and magnesium alloys, to carbon fiber composites, have made their way into mass-produced passenger cars.
Automotive Ductile Iron Castings for High Temperature ApplicationsJ2582_201801 (Current)1/9/2018
This SAE Standard covers the hardness, chemical analysis and microstructural requirements for ductile iron castings intended for high temperature service in automotive and allied industries. Commonly known as SiMo ductile iron, typical applications are in piston-engine exhaust manifolds and turbocharger parts. Castings may be specified in the as-cast or heat treated condition. For design purposes, the Appendix provides general information on the application of high temperature ductile iron castings, their processing conditions, chemical composition, mechanical properties and microstructure.
Metals Technical Committee
Magnesium Wrought AlloysJ466_201801 (Current)1/9/2018
This SAE Standard covers the most common magnesium alloys used in wrought forms, and lists chemical composition and minimum mechanical properties for the various forms. A general indication of the usage of the various materials is also provided.
Metals Technical Committee
Magnesium Casting AlloysJ465_201801 (Current)1/9/2018
This document has not changed other than to put it into the new SAE Technical Standards Board Format This SAE Standard covers the most commonly used magnesium alloys suitable for casting by the various commercial processes. The chemical composition limits and minimum mechanical properties are shown. Over the years, magnesium alloys have been identified by many numbering systems, as shown in Table 1. Presently, SAE is recommending the use of the use of the UNS numbering system to identify those materials. Other equally important characteristics such as surface finish and dimensional tolerances are not covered in this standard.
Metals Technical Committee
Chemical Check Analysis Limits Nickel, Nickel Alloys, and Cobalt AlloysAMS2269F (Historical)12/5/2017
This specification defines limits of variation for determining acceptability of the composition of cast or wrought nickel, nickel alloy, and cobalt alloy parts and material acquired from a producer.
AMS F Corrosion Heat Resistant Alloys Committee
Chemical Check Analysis Limits Titanium and Titanium AlloysAMS2249H (Historical)6/21/2017
This specification defines limits of variation for determining acceptability of the composition of cast or wrought titanium and titanium alloy parts and material acquired from a producer.
AMS G Titanium and Refractory Metals Committee
Recovering Metals from Electronic WasteTBMG-270326/1/2017
End-of-life electronic devices such as smartphones, computers, televisions, and other electronics contain significant amounts of valuable metals including base metals (zinc, tin, lead, nickel, and copper), precious metals (silver, gold, and palladium), and rare earth magnets (neodymium, yttrium, samarium). Some electronic scrap is currently landfilled or incinerated, and there is a need to develop more effective processes to capture these valuable metals along with keeping them out of the environment.
Synchronous Motor with Silicon Steel Salient Poles Rotor and All Coils Placed on the Stator2017-01-16063/28/2017
In this paper, we consider a new design of synchronous motor with salient poles rotor and all coils placed on the stator. This design, uses a laminated silicon steel rotor, which is not so expensive as a rotor with super strong permanent magnets. This design of machine eliminates copper rings on the rotor and brushes which is used in regular synchronous motors, and eliminates disadvantages involved with these arrangements. In an earlier publication, authors considered the opportunity realization of synchronous mode operation in the machine with salient pole rotor and DC stator excitation. Now, we consider the new synchronous mode operation with individual DC excitation of each the alternative current (AC) windings for realization the first, second and third phase synchronous machines. In theoretical basics of analyses and design of synchronous motors we pay more attention to the single-phase motor because it is the basis for design polyphase synchronous machines. In the paper, we suggest a new single-phase, two phase and three phase synchronous motor configuration. These synchronous machine configurations can work in DC mode operation without changing the electronic power circuit. This property can also be used for starting synchronous machines. The prototype, two phase synchronous motor was designed and tested. The single-phase motor was tested on the base two phase motor. Results of the test from these prototype machines confirm the main useful properties of synchronous machines.
Gladyshev, Sergey P., Gladyshev, Pavel, Okrainskaya, Irina
Magnetic Form of Heavy Rare-Earth Free Motor for Hybrid Electric Vehicle2017-01-12213/28/2017
As heavy rare earth elements are become less prevalent, because one-tenth as often in ore deposits as light rare earth elements. Future usage of need to be reduces heavy rare earth, because of resource risks and costs. As such, a method was developed to recover reductions in coercive force and prevent demagnetization temperature from reducing without adding any heavy rare earth elements. First, a heavy rare-earth-free magnet was developed by hot deformation, which limits growth of crystal grain size, and relationships were clarified between coercive force and optimal deforming temperatures, speed, and total rare earth amounts for heavy rare-earth-free magnets. Second, it was made clear that the permeance coefficient can be increased by reshaping the flux barriers, and that the developed hot deformed magnet can be adopted. In this study, a new motor was developed using heavy rare-earth-free hot deformed magnets with performance and marketability equal to or higher than those of traction motors equipped in one-motor sport hybrid systems.
Soma, Shingo, shimizu, Haruhiko, Shirado, Eiji, Fujishiro, Satoshi
Development of Chemical Process for Recovering High-quality Rare-earth Oxides from HV Motor Magnets2017-01-12783/28/2017
In the automobile industry, interest in the prevention of global warming has always been high. The development of eco cars (HV, EV etc.), aimed at reducing CO2 emissions during operation, has been progressing. In the announcement of its "Toyota Environmental Challenge 2050", Toyota declared its commitment to creating a future in which people, cars, and nature coexist in harmony. In this declaration, Toyota committed to reducing CO2 emissions not only during operation but also over the entire life cycle of vehicles, and to using resources effectively based on a 4 R’s approach (refuse, reduce, reuse, and recycle). Although eco cars decrease CO2 emissions during operation, most of them increase CO2 emissions during manufacturing. For example, the rare-earths (Nd, Dy etc.) used in the magnets of driving motors are extracted through processes that produce a significant amount of CO2 emissions. The common process for recycling the rare-earths used in magnets can recover high-purity rare-earths by electrolysis. However, this process is costly and also produces a significant amount of CO2. Toyota has developed a chemical recycling process for producing high-quality rare-earth oxides that is economical and reduces CO2 emission during material production by 80% without the use of electrolytic refining. This paper describes this chemical recycling process for rare earth components and, in addition, introduces an energy-saving, vehicle-to-vehicle resource recycling flow.
Isomura, Keisuke
Self-Excited Wound-Field Synchronous Motors for xEV2017-01-12493/28/2017
Compact, high efficiency and high reliability are required for an xEV motor generator. IPM rotors with neodymium magnets are widely applied for xEV motors to achieve these requirements. However, neodymium magnet material has a big impact on motor cost and there is supply chain risk due to increased usage of these rare earth materials for future automotive xEV’s. On the other hand, a wound-field rotor does not need magnets and can achieve equivalent performance to an IPM rotor. However, brushes are required in order to supply current to the winding coil of the rotor. This may cause insulation issues on xEV motors which utilize high voltage and high currents. Therefore, it is suggested to develop a system which supplies electric energy to the rotor field winding coil from the stator without brushes by applying a transformer between stator coil and rotor field winding. Specifically, add auxiliary magnetic poles between each field winding pole and wind sub-coils to these poles. The magnetic flux generated from the stator induces a field current in the sub-coils. Rectifying the induced current by a diode enables applying direct current to the field windings of the rotor. This paper confirms the equivalent performance between an IPM rotor and wound-field rotor by FEM simulation.
Seguchi, Masahiro
Aerospace & Defense Technology: December 201616AERP1212/1/2016
Additive Manufacturing How 3D Printing Will Transform the A&D Support Chain Advances in Lightweight Electronics Protection Conformal Coatings Increase Reliability of Aerospace and Military Assemblies Powering Outer Space An In-Depth Look at Aerospace Battery Technology Using High Bandwidth Oscilloscopes to Analyze Radar and Electronic Warfare Systems Bio-inspired Airborne Infrastructure Reconfiguration (BioAIR) EMI Analysis Software Helps Telescope Group Simulate RFI Mitigation Epitaxial Growth of Rhenium with Sputtering Processing and Characterization of Polycrystalline YAG (Yttrium Aluminum Garnet) Core-Clad Fibers Multi-Scale Analysis of Deformation and Failure in Polycrystalline Titanium Alloys Under High Strain Rates Abrasion Testing of Products Containing Nanomaterials Spectrum Fatigue of 7075-T651 Aluminum Alloy under Overloading and Underloading
Multi-Phase Ceramic SystemTBMG-2550010/1/2016
Bearing surfaces are typically either metal-on-metal (MOM), ceramic-on-ceramic (COC), or metal-on-polyethylene (MOP). MOM and MOP couplings have the drawback that metallic or polyethylene particles can sometimes separate from the couplings, which can cause significant problems, particularly in a hip or joint replacement. COC couplings are less likely to lose particles due to wear, which makes them more biocompatible, but they are more susceptible to fracture. COC couplings also have a tendency to squeak as they move. Innovators at NASA’s Glenn Research Center have developed a technique using rare earth elements to fabricate a dual-phase ceramic composite that combines a wear-resistant phase and a solid-state lubricant phase. The result is a coupling material that, compared to currently used materials, exhibits a tenfold reduction in the friction coefficient, a sixfold reduction in wear, and a significant reduction in debris caused by wear. Glenn’s groundbreaking rare-earth aluminate composite has considerable potential, not only in biomedical applications, but also in commercial and industrial sectors.
Honda's new e-motor slashes expensive rare-earth content16AUTP09_109/1/2016
Honda Motor Co. and Daido Steel Ltd. recently scored a strategic win when they announced the first production application of a new magnet material for electrified vehicle motors. The material-hot deformed neodymium-is being used first in a new permanent-magnet traction motor powering Honda's 2017 Freed Sport Hybrid compact minivan. Significantly, the material is not a “heavy” rare-earth metal, one that requires “doping” with dysprosium or terium rare earths to achieve high heat-resistance characteristics. Yet it has the high magnetic and thermal performance necessary for use in EV and hybrid vehicle e-motors, according to the companies.
Brooke, Lindsay
Titanium Alloy, Round Bar and Wire 3AI - 8V - 6Cr - 4Mo - 4Zr Consumable Electrode Melted Solution Heat Treated and Cold DrawnAMS4957F (Historical)7/11/2016
This specification covers a titanium alloy in the form of round bar and wire, 0.625 inch (15.88 mm) and under in nominal diameter or thickness.
AMS G Titanium and Refractory Metals Committee
Effect of Thermal Exposure Time on the Relaxation of Residual Stress in High Pressure Die Cast AM602016-01-04234/5/2016
Magnesium alloys are becoming more commonly used for large castings with sections of varying thicknesses. During subsequent processing at elevated temperatures, residual stresses may relax and become a potential mechanism for part distortion. This study was conducted to quantify the effects of thermal exposure on residual stresses and relaxation in a high pressure die cast magnesium (AM60) alloy. The goal was to characterize relaxation of residual stresses at temperatures that are commonly experienced by body components during a typical paint bake cycle. A residual stress test sample design and quench technique developed for relaxation were used and a relaxation study was conducted at two exposure temperatures (140°C and 200°C) over a range of exposure times (0.25 to 24 hours). The results indicate that a significant amount of residual stress relaxation occurred very rapidly during exposure at both exposure temperatures.
Hill, Haley, Zindel, Jacob, Godlewski, Larry
The New Generation Front Wheel Drive Hybrid System2016-01-11674/5/2016
Introducing all-new front wheel drive hybrid system installed in the 2016 Toyota Prius. This system was completely re-designed to maximize the potential of THS-II (Toyota Hybrid System-II). This system was designed to be able to minimize the mechanical and electrical losses from the previous generation system, improve environmental performance, and also tried to reduce size and weight. We’d like to take this opportunity to introduce the new technology of each component, and hybrid system performance.
Fushiki, Shunsuke
Lightweight Materials for Automotive Applications: A Review2015-36-02199/22/2015
Today, in order to optimize the resources usage and reduce the air pollution, the automobile industry is facing new challenges, with the necessity to improve engines fuel economy, enhance vehicles autonomy and reduce the CO2 emission. One of the solution, which is being much researched, is the car components weight reduction. There is a range of new materials that have been developed to attend the new weight standards. Together with lightweight these materials must also deliver acceptable mechanical properties, easy to manufacture and to assembly capability, good appearance, high durability, good cost-benefit relation and in some cases also acceptable impact energy absorption. This paper presents a review of some of the lightweight materials that are being applied in automobiles, like Carbon Fiber, Aluminum Alloy, Magnesium Alloy, Hybrid Material and Polymer Composites. The physical characteristics, applicability in automotive components, manufacturability and relative cost are shown for each material.
Haber, Daniel
DC TransformerTBMG-225488/1/2015
A component-level DC transformer was developed in which no alternating currents or voltages are present. It operates by combining features of a homopolar motor and a homopolar generator, both DC devices, such that the output voltage of a DC power supply can be stepped up (or down) with a corresponding step down (or up) in current. The DC transformer should be scalable to low-megawatt levels, but is more suited to high-current than high-voltage applications.
Supply of High-Tech Metals at RiskTBMG-222246/1/2015
DOE Focuses on Developing Materials to Improve Vehicle Efficiency2015-01-04054/14/2015
The U.S. Department of Energy Vehicles Technology Office developed requirements and identified technology gaps for lightweight and propulsion materials for light-duty and heavy-duty vehicles. This paper provides examples of research under development that address the highest priority technology gaps. These examples are synergistic with the Multi-Material Lightweight Vehicle demonstration project, which will be covered in detail in subsequent papers. The purpose of this paper is to show other developments in progress that have the potential to help address technology gaps identified by the demonstration project.
Schutte, Carol
Comparative Corrosion Assessment of Coated Alloys for Multi-Material Lightweight Vehicle Architectures2015-01-07384/14/2015
The purpose of this study was to conduct a comparative corrosion assessment of alloys and coating schemes of interest for the fabrication of multi-material lightweight vehicle architectures. Alloys considered for this application included galvanized high strength low alloy steel, aluminum alloy AA6111 and magnesium alloy ZEK100. The coating scheme considered for corrosion protection included a layered paint top-coat scheme that was applied to a pre-treated surface. The pre-treatments included an alloy-specific commercial conversion coating (CC) and a plasma electrolytic deposition (PED) process that was applied only to the ZEK100 material. The corrosion assessment of the scribed coated alloy panels was conducted after 1000 h exposure in the ASTM B117 salt fog environment. Characterization of the mode and extent of corrosion damage observed and the role played by the exposed alloy microstructure utilized both light optical microscopy and electron microscopy. The results of this comparative study are discussed in the context of the suitability of the commercial coating schemes to provide sufficient corrosion protection of the lightweight alloys under study.
Kish, Joseph R., Cano, Zach, Kobylecky, Alexandra, McDermid, Joseph, Skszek, Timothy
Low Er-Doped Yttrium Gallium Garnet (YGG) as Active Media for Solid-State Lasers at 1651 nmTBMG-218074/1/2015
The typical approach for producing laser output at the 1651-nm wavelength is via nonlinear frequency conversion. Lasers based on nonlinear conversion are complex, and it is very difficult to provide stability over time and over a wide range of operating temperatures. The efficiency of such optical sources is also low. A much more promising approach is the use of active media that allows for the development of solid-state lasers (SSL) with spectral emission at 1651 nm. An important requirement for this active medium is the ability to support in-band pumping with a low quantum defect since this approach leads to significant improvement in efficiency of SSLs and excellent beam characteristics due to low thermal stress of the active media.
Effect of Aluminum on Mechanical and Tribological Properties of Automotive Grade Gray Cast Iron2015-26-00661/14/2015
Mechanical and wear properties of Al alloyed gray cast iron (0.5% and 1.0%) were compared with that of Mo (1.0%) and Cu (0.77%) alloyed gray cast iron in this investigation. All the alloys showed pearlitic microstructure. The graphite morphology varied due to varying chemistry. The fracture surface showed “cabbage” like dimpled morphology indicating the predominant ductile fracture. It was found that the Mo containing cast iron show 25 to 30% higher strength and 6 to 7 times better wear resistance compared to Al containing cast irons. The worn surface showed oxide formation during sliding.
Vadiraj, Aravind, Tiwari, Shashank, Dasare, Ashutosh
New Metal Alloy as Strong as TitaniumTBMG-2123212/17/2014
Materials scientists from North Carolina State University, Raleigh, NC, and Qatar University have developed a new high-entropy metal alloy that, they say, has a higher strength-to-weight ratio than any other existing metal material. High-entropy alloys consist of five or more metals in roughly equal amounts. The researchers say that strong, lightweight materials, may be very useful in prosthetic devices, as well as many other uses.
Imaging Method Might Mean Earlier Cancer DetectionTBMG-2114912/1/2014
Engineers at Rutgers University, New Brunswick, NJ, say that a new medical imaging method they are developing may help physicians detect cancer and other diseases earlier than before, speeding treatment, and reducing the need for invasive, time-consuming biopsies. Their technique uses nanotechnology to reveal small cancerous tumors and cardiovascular lesions deep inside the body.
Solar Pumped Fiber Laser for Solar Sail Propulsion and Remote Power TransferTBMG-205379/1/2014
A new method has been developed to create coherent laser light efficiently with direct optical coupling of the Sun’s energy into the gain medium for multiple uses. New advances in solar cell photovoltaic (PV) technologies have greatly improved their efficiencies, mostly by improving their ability to convert many wavelengths or wider bands of the solar spectrum to electricity. New advances in actively doped fibers and optical glasses have been shown to produce very broad, multi-line absorption bands as well as stimulated emission lines, or laser lines. By designing the optical cavity system to feed back all emission bands into the gain media for amplification, a multi-wavelength source can be generated requiring no electronics.
A New Multi Air Gap Motor with Trench Shaped Coil for HEV Applications2014-01-18704/1/2014
This paper proposes a new multi air gap motor with trench-shaped coil. The proposed motor has high torque without rare earth magnets compared to conventional single air gap motors due to its multiple air gap and ferrite permanent magnet (PM) assisted segment rotor poles. Firstly, the basic structure and features of proposed motor is shown: three stator cores, integrated a set of three phase windings, and an annular rotor core with magnetic saliency at three sides and ferrite magnets. Then, the performance of proposed new motor and well-known single air gap IPMSM with rare earth magnet are compared by FEA. Secondly, the simple winding method similar to the conventional motor is clarified. Next, practical design of the 3-D magnetic circuit with laminated steel is discussed. Eddy current generated by the magnetic flux passing through the laminated steel in the core stacking direction is focused, and methods for reducing eddy current loss are shown. Finally, performances of proposed motor are verified by the prototype machine in test bench and actual vehicle. From these discussions, the possibility of low cost and high torque motor without rare earth magnets is shown.
Kondo, Keiji, Maekawa, Takeo, Kusase, Shin
Damage Mechanisms of Stainless Steels under Thermal Fatigue2014-01-09174/1/2014
Thermal fatigue of austenitic and ferritic stainless steel grades has been experimentally and numerically investigated. A special test has been developed to determine the thermal fatigue resistance of clamped V-shaped specimens. This test permits to impose thermal cycle by alternating resistance heating and air cooling. The thermal fatigue life of a specimen is expressed as the number of cycles to failure. For a given grade, the fatigue life depends on the maximal and minimal temperature of the cycle, holding time at the maximal temperature and specimen thickness. The advantage of this V-shape test is that it is a simple procedure quite representative of the thermal fatigue process occurring in an exhaust manifold. This test is well suited to perform a study of damage mechanisms and to compare stainless steel grades. Examination of the failed specimens indicated that cracks could be mainly attributed to out-of-phase (OP) thermal fatigue process especially in case of ferritic grades. For austenitic steels (AISI304 EN1.4301, AISI321 EN1.4541 or AISI308 EN1.4828) at a critical temperature or above, an in-phase (IP) thermal fatigue mechanism is coupled with oxidation and creep, which are further significantly reducing the lifetime. Therefore, the service temperature range of austenitic grades is more limited than ferritic grades. Despite their lower yield stress at high temperature, ferritic grades exhibit a very good thermal fatigue resistance at elevated peak temperatures because of their very good cyclic oxidation behavior, creep resistance and their low coefficient of thermal expansion. Consequently a dedicated titanium or niobium stabilized ferritic offer was developed for the hot part of the exhaust system (from manifold to catalytic converter) that includes 14%Cr (K11X 429/425 1.4595), 17%Cr (K41X 441 1.4509) and 19%Cr (K44X modified 444 1.4521) grades in order to cover the peak temperature range from 900°C to 1050°C.
Santacreu, Pierre-Olivier, Faivre, Laurent, Acher, Antoine
Moving Magnet Voice Coil Actuators Offer Controllable Movement for High-Duty-Cycle ApplicationsTBMG-190702/1/2014
There are two types of voice coil actuators: moving coil and moving magnet. The materials of construction are similar, since they both use rare earth magnets, steel, copper wire, and basic insulation materials. There is a tendency to want to say one type is better suited for certain applications; however, there are many different sizes and shapes of voice coil actuators, making it difficult to make blanket statements about which type of actuator works better, and where.
Investigation on microstructure, mechanical and wear properties of alloyed gray cast iron for brake applications2013-01-288111/27/2013
The strength and wear resistance of four alloyed cast irons with elements like Ni. Mo, Cu, Cr and Al have been compared and analyzed. The increased hardness is reducing the wear resistance of the alloy due to graphite flakes. Higher carbon produces more graphite flakes which act as weak points for reducing strength and wear resistance. The wear rate increases for harder cast iron sample with more graphite flakes. Wear rate drastically increases with increase in carbon equivalent. Strength was found to decrease for samples with higher graphite flakes. The wear debris consisted of graphite flakes in platelet like morphology along with iron particles from the matrix. The presence of carbon at the sliding interface also sometimes decreases wear rate.
Vadiraj, Aravind, Tiwari, Shashank
Chemical Check Analysis Limits Titanium and Titanium AlloysAMS2249G (Historical)10/14/2013
This specification defines limits of variation for determining acceptability of the composition of cast or wrought titanium and titanium alloy parts and material acquired from a producer.
AMS G Titanium and Refractory Metals Committee
Enhancing the Performance of Microperforated Panel Absorbers by Designing Custom Backings2013-01-19375/13/2013
Micro-perforated (MPP) panels are acoustic absorbers that are non-combustible, acoustically tunable, lightweight, and environmentally friendly. In most cases, they are spaced from a wall, and that spacing determines the frequency range where the absorber performs well. The absorption is maximized when the particle velocity in the perforations is high. Accordingly, the absorber performs best when positioned approximately a quarter acoustic wavelength from the wall, and larger cavity depths improve the low frequency absorption. At multiples of one half acoustic wavelength, the absorption is minimal. Additionally, the absorption is minimal at low frequencies due to the limited cavity depth behind the MPP. By partitioning the backing cavity, the cavity depth can be strategically increased and varied. This will improve the absorption at low frequencies and can provide absorption over a wide frequency range. In this work, backing substrates have been developed to enhance the absorption performance. Maa's model is first reviewed. Then, different MPP and backing substrate combinations are analyzed using Maa's theory and the boundary element method. The broadband absorptive behavior is validated via measurement in a square impedance tube. Measured results agree reasonably well with analysis.
Hua, X., Herrin, D. W., Jackson, P.
Development of Rare Earth-saving Magnet Using Localized Diffusion Method2013-01-17574/8/2013
Nd₂Fe₁₄B sintered magnets are used in the drive motors of hybrid, electric and other vehicles. A magnet in which rare earth content is reduced by means of a localized diffusion method has been developed in order to reduce the volume of dysprosium. The distribution of the demagnetization fields in a motor is not uniform, so the necessary coercivity distribution for the magnets was quantified using Computer-Aided Engineering (CAE). Then material specifications of the localized dysprosium diffusion satisfied with this coercivity distribution was determined, and optimal manufacturing conditions including the position of dysprosium diffusion were set. The coercivity distribution in every position of the magnet using localized diffusion method was inspected. As a result, the magnet was satisfied with coercivity distribution demanded by CAE. Furthermore, evaluation of motor characteristics, especially the demagnetizing characteristic concerned with dysprosium reduction, showed this developed magnet to possess identical characteristics to a conventional magnet. Dysprosium resources represent a particular issue among the rare earths more generally, and the technology developed in this project is able to reduce dysprosium use in magnets by approximately 30% without compromising motor performance.
Higashi, Takayuki, Miyoshi, Takehiro, Kato, Ryutaro, Kono, Michihisa, Inoue, Masashi, Nagumo, Toshiyuki, Fukui, Takahiro, Ohsaki, Kojiro, Iwasaki, Makoto
Determination of Costs and Benefits from Implementing an Engine Health Management SystemARP4176 (Historical)2/5/2013
This ARP provides an insight into how to approach a cost benefit analysis (CBA) to determine the return on investment (ROI) that would result from implementing a propulsion Prognostics and Health Management (PHM) system on an air vehicle. It describes the complexity of features that can be considered in the analysis, the different tools and approaches for conducting a CBA and differentiates between military and commercial applications. This document is intended to help those who might not necessarily have a deep technical understanding or familiarity with PHM systems but want to either quantify or understand the economic benefits (i.e., the value proposition) that a PHM system could provide.
E-32 Aerospace Propulsion Systems Health Management
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