Browse Topic: Ceramics

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Factors and Requirements for Adhesive Selection in Medical Devices, Part 1TBMG-5214912/1/2024
The global medical device market is projected to reach a value of $656 billion USD by 2032 with a CAGR of 3 percent over the coming decade.1 The preceding decades of globalization and increased prosperity has provided advancement in both medical technology and access to advanced medical care for a greater proportion of the world’s population. Further, an aging population in North America, Europe, and parts of Asia will increase the need for healthcare-related services and medical devices in the coming decades. At present, the North America market continues to dominate the industry, accounting for approximately 43 percent of the market’s revenue share; however, markets in the Asia-Pacific region have the highest expected growth rates in the coming decades.1 Growth and innovation in the medical device market will be critical in the years to come.
RESEARCH OF THE EFFECTS OF INTEGRATION INTO ARMOR ON THE PERFORMANCE OF SPINTRONIC MICROWAVE DETECTORS2024-01-333411/15/2024
ABSTRACT The authors studied the effects of different types of armor on the performance of spin-torque microwave detectors (STMD). Working prototypes of novel nano-sized spintronic sensors of microwave radiation for battlefield anti-radar and wireless communications applications are being integrated into Sensor Enhanced Armor (SEA) and Multifunctional Armor (MFA) and tested in SEA-NDE Lab at TARDEC. The preliminary theoretical estimations have shown that STMD based on the spin-torque effect in magnetic tunnel junctions (MTJ), when placed in the external electromagnetic field of a microwave frequency, can work as diode detectors with the maximum theoretical sensitivity of 1000 V/W. These STNO detectors could be scaled to sub-micron size, are frequency-selective and tunable, and are tolerant to ionizing radiation. We studied the performance of a STMD in two different dynamical regimes of detector operation: in well-known traditional in-plane regime of STMD operation and in recently
Bankowski, Elena, Meitzler, Thomas, Pesys, Tomas
Physical Durability of Advanced Ceramic Substrates for Ultra Low Emissions Applications2022-01-06593/29/2022
In the face of tightening GHG regulations, vehicle ICE powertrains must now adopt new methods to achieve superior fuel economy and further reduce tailpipe gaseous emissions. Some recent strategies by OEMs for meeting these objectives include the downsizing of their engine displacement, the adoption of aggressive turbocharging, and the close-coupled locating of the exhaust aftertreatment. Ceramic substrates, the principal enabling technology within established aftertreatment systems, must further demonstrate enhanced performance qualities to survive and continue to perform in this more severe operating environment. This paper will summarize performance studies conducted on advanced ceramic substrates of high porosity and thin wall monolith cordierite design. The testing results correspond with OEM technical expectations and include the following: thermal shock resistance studies from engine exhaust heat up events, mechanical strength evaluation from harsh vibration exposure, and
Craig, Angus, Warkins, Jason, Bhargava, Rajesh
Effect of Material Anisotropy on Thermal-Mechanical Instabilities in Metal-Free Friction Materials2021-01-128910/11/2021
An anisotropic ceramic matrix composite (CMC), which consists of a silicon carbide (SiC) based ceramic matrix reinforced with carbon (C) fibers, is considered as a metal-free friction material replacement in brake and clutch applications. The fibers are assumed to have a circular cross-section, arranged unidirectionally and packed in a rectangular array without the presence of voids. The rule of mixture showed the C-SiC composite to be transversely isotropic with the circumferential plane as the plane of isotropy. A set of parametric studies have been performed to computationally investigate the dominant parameters that affect thermal-mechanical instabilities. It is found that the chance of thermal buckling in the friction disc can be minimized by reducing the elastic moduli in the radial and circumferential directions, or by reducing the coefficient of thermal expansion in the same directions. Meanwhile, the material properties in the axial direction do not have a significant effect
Shaahu, Joseph-shaahu, Koranteng, Kingsford, Yi, Yun-Bo
Decoding Genuine Ceramic Pad Formulations- Materials and Processing2021-01-127710/11/2021
The need to develop genuine ceramic composites for PV applications arose to overcome the challenges associated with traditional semi-metallic pads. The main focus is to achieve better performance, low noise, better pad and rotor wear, and low dust compared to semi- metallic pads. In general, brake pads convert kinetic energy to thermal energy through friction, and operating temperature in semi-metallic brake pads is higher due to the presence of steel having high thermal conductivity. Over the last decade, the customer preference has moved over to ceramic pads due to light coloured pad surface, low rotor and pad wear and low dust compared to semi-metallic pads. The traditional steel has been replaced by Aramid, engineered ceramic fibre, potassium titanate (TISMO D), lapinus fibre (RB 250) to impart similar/better performance. The current work investigates the characterisation of genuine ceramic and semi-metallic composites. Three genuine ceramic and one semi-met composite have been
Tomar, Bharat, Ali, Sharafat, Ellis, Keith, Choudhary, Yogesh
Recommended Practice for Determining Material Properties of Li-Battery Cathode Active MaterialsJ3021_202105 (Current)5/28/2021
This SAE Recommended Practice provides a set of test methods and practices for the characterization of lithium ion battery cathode active material. It is beyond the scope of this document to establish criteria for the test results, as these are usually established between the vendor and customer. It should be noted that materials properties can vary substantially between classes of materials (e.g., LNO and LFP) and caution should be exercised when attempting to directly compare their chemical and physical properties. While these distinctions are important for the manufacturer, this document focuses on the techniques to measure the materials properties and not their absolute or relative values. Future materials such as solid-state batteries and sulfides are beyond the scope of this document. It is beyond the scope of this document to examine the rheological properties of the cathode material dispersed in a coating slurry since such properties are influenced by the conductive additive
Battery Materials Testing Committee
Recommended Practice for Determining Material Properties of Li-Battery Cathode Active MaterialsJ3021_202105-TEST-REC (Historical)5/28/2021
This SAE Recommended Practice provides a set of test methods and practices for the characterization of lithium ion battery cathode active material. It is beyond the scope of this document to establish criteria for the test results, as these are usually established between the vendor and customer. It should be noted that materials properties can vary substantially between classes of materials (e.g., LNO and LFP) and caution should be exercised when attempting to directly compare their chemical and physical properties. While these distinctions are important for the manufacturer, this document focuses on the techniques to measure the materials properties and not their absolute or relative values. Future materials such as solid-state batteries and sulfides are beyond the scope of this document. It is beyond the scope of this document to examine the rheological properties of the cathode material dispersed in a coating slurry since such properties are influenced by the conductive additive
Battery Materials Testing Committee
Reconfigurable Electronics Based on Multiferroics and Nanomagnetism21AERP02_092/1/2021
Research could lead to the development of new materials with large magnetoelectric (ME) coupling for next-generation multifunctional devices, including, multi-state (neuromorphic-like) circuits and memories, and E-field tunable microwave resonators for secure communications. Air Force Research Laboratory, Arlington, Virginia Multifunctional magnetoelectric materials with high exchange represent a missing “holy grail” of materials physics. To combine polarization and magnetization in the same solid is nothing short of actually controlling the fundamental nature of electromagnetism in matter. Although magnetoelectricity (ME) is an intrinsic phenomenon in some natural materials at low temperature, such single-phase materials suffer from an extremely weak ME exchange. In contrast, composites consisting of magnetostrictive and piezoelectric phases can feature dramatically larger ME coefficients. This proposed program focuses on achieving the disruptive potential of emerging multifunctional
A Comprehensive Way to Use Bonding to Improve RF Performance of Low Noise AmplifiersTBMG-385262/1/2021
Is RF engineering a form of black magic? This article analyzes the challenges faced in the development of the ADH519S, an 18-GHz to 31-GHz low noise amplifier (LNA) for the aerospace market. The die used in the product development for space was originally released to the commercial industry in the LC4 package. To release this product for the space and high-reliability market and comply with MIL-PRF-38535 standards, this part was assembled using the most suitable and available hermetically sealed ceramic package. This article presents a unique solution and process education to improve RF performance via bonding. This product development process presented the following challenges:
A Comprehensive Way to Use Bonding to Improve RF Performance of LOW NOISE AMPLIFIERS21AERP02_052/1/2021
Is RF engineering a form of black magic? This article analyzes the challenges faced in the development of the ADH519S, an 18-GHz to 31-GHz low noise amplifier (LNA) for the aerospace market. The die used in the product development for space was originally released to the commercial industry in the LC4 package. To release this product for the space and high-reliability market and comply with MIL-PRF-38535 standards, this part was assembled using the most suitable and available hermetically sealed ceramic package. This article presents a unique solution and process education to improve RF performance via bonding. This product development process presented the following challenges: This article reviews the different methods used to overcome these challenges and how to achieve the best stability and noise figure performance from the new hermetically sealed ceramic package.
Overlap Shear Test for Automotive Type Sealant for Stationary Glass BondingJ1529_202101 (Current)1/7/2021
This SAE Recommended Practice defines a procedure for the construction and testing of glass to metal lap shears for determining shear strength of sealant adhesives for automotive stationary glass bonding. This procedure can also be used for fiber reinforced plastic (FRP) when used in place of metal.
Materials, Processes and Parts Council
Wear Performances of Gray Cast Iron Brake Rotor with Plasma Electrolytic Aluminating Coating against Different Pads2020-01-162310/5/2020
Gray cast iron brake rotor experiences substantial wear during braking and contributes largely to the wear debris emissions. Surface coating on the gray cast iron rotor represents a trending approach dealing with the problems. In this research, a new plasma electrolytic aluminating (PEA) process was used for preparing an alumina-based ceramic coating with metallurgical bonding to the gray cast iron. Three different types of brake pads (ceramic, semi-metallic and non asbestos organic (NAO)) were used for tribotests. Performances of PEA coatings vs. different brake pad materials were comparatively investigated with respect to their coefficients of friction (COFs) and wear. The PEA-coated brake rotor has a dimple-like surface which promotes the formation of a thin transferred film to protect the rotor from wear. The transferred film materials come from the wear debris of the pads. The secondary plateaus are regenerated on the brake pads through compacting wear debris of the pads. The wear
Cai, Ran, Zhang, Jingzeng, Tjong, Jimi, Nie, Xueyuan
Origami-Inspired Miniature ManipulatorTBMG-3783610/1/2020
Minimally invasive laparoscopic surgery, in which a surgeon uses tools and a tiny camera inserted into small incisions to perform operations, has made surgical procedures safer for both patients and doctors. Surgical robots further assist surgeons by allowing them to manipulate multiple tools at once with greater precision, flexibility, and control than is possible with traditional techniques. These robotic systems are extremely large, often taking up an entire room and their tools can be much larger than the delicate tissues and structures on which they operate.
Eliminating Latency in Next-Gen Wi-Fi 6E DevicesTBMG-3785310/1/2020
When Wi-Fi 6 (IEEE 802.11ax) was introduced by the Wi-Fi Alliance, the standard was initially designed to operate within the licensed exempt bands between 1 and 6 GHz. Then, on April 23, 2020, the Federal Communications Commission (FCC) announced that it was adopting rules to open the 6 GHz band (5.925–7.125 GHz) for unlicensed use for Wi-Fi 6 as well.
New Coating Process Lights Porous Electronics and SensorsTBMG-373648/1/2020
Researchers have shown how to coat glass and plastic with porous titanium dioxide. The fabrication process is straightforward, the materials are cheap, and the ceramic’s gas sensing performance is considerably improved compared with current devices.
Nano-Infused Ceramic Can Report its own HealthTBMG-368305/1/2020
A ceramic was developed that becomes more electrically conductive under elastic strain and less conductive under plastic strain. The material could lead to a new generation of sensors embedded into structures like buildings, bridges, and aircraft able to monitor their own health.
Additive Manufacturing Method for Sub-Microscale Three-Dimensional StructuresTBMG-363764/1/2020
NASA Goddard Space Flight Center has developed a substantial advancement in additive manufacturing technology. The method eliminates most material restrictions, enabling fabrication of sub-microscale three-dimensional structures composed of nearly any material that is compatible with chemical vapor deposition (CVD) including metallic and ceramic materials. Current technology for the production of microscale three-dimensional structures, such as two-photon lithography, is generally limited to the use of photosensitive polymeric materials.
Fabrication and Electrical Characterization of Correlated Oxide Field Effect Switching Devices for High Speed ElectronicsTBMG-366064/1/2020
Metal insulator transitions (MITs) in oxides are an intriguing problem from both a fundamental materials physics and an applied technology perspective. Though the precise roles of electron correlations and lattice distortions on the phase transition remains an active area of research, many recent theoretical studies have suggested intimate interplay among the orbital splitting/polarization, correlation effects, and Peierls dimerization in the 3d1 system. Occupied states have been probed by x ray photoelectron spectroscopy (XPS), and a rough structure of unoccupied 3d-like states have been deduced by O K-edge x-ray absorption measurements. NbO2, a 4d1 system, like VO2 crystallizes in a distorted rutile type structure with Nb dimers and undergoes a temperature induced MIT, albeit at a considerably higher temperature of ~1083 K. It is commonly accepted that because 4d orbital valence states are more dispersed in both space and energy, Mott physics is less important in 4d transition metal
Alternatives to Cadmium PlatingAIR4160B (Current)3/24/2020
To document and provide access to information obtained by an industry survey.
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
Celebrating Women in Engineering & Science: Renee Bernstein, CEO, Cotronics CorporationTBMG-361673/1/2020
Welding Ceramics with LasersTBMG-359922/1/2020
Ceramics have been challenging to weld together because they need extremely high temperatures to melt, exposing them to extreme temperature gradients that cause cracking. Ceramic materials are biocompatible, extremely hard, and shatter-resistant, making them ideal for biomedical implants and protective casings for electronics.
Thermally Conductive Polymer FilmsTBMG-359772/1/2020
Polymers are commonly used for thermal insulation as they are excellent at trapping heat. Thin polymer films were developed that conduct heat — an ability normally associated with metals. The films, which are thinner than plastic wrap, conduct heat better than many metals including steel and ceramic.
Mechanical and Corrosion Behaviour of Al 7075 Composite Reinforced with TiC and Al 2 O 3 Particles2019-28-009410/11/2019
Various research regarding new types of fabrication and modifications of Aluminium alloy to improve the existing properties are going on. The wide range application of aluminium alloy is in aerospace and Automobile Industries. The demand for this material improved by mechanical properties with little to zero increment in weight. The current work is based on the fabrication of hybrid aluminium metal matrix composites with the addition of TiC (Titanium Carbide) and Al2O3 (Aluminium Oxide) reinforcement particle using stir casting technique. Three types of hybrid composite samples were prepared based on the weight percentage 5% Al2O3+0% TiC (sample-1), 8% Al2O3 + 12% TiC (sample-2), 20% Al2O3+15% TiC (sample-3). The objective of the study is to analyze the mechanical and corrosion properties of the hybrid composite with the influence of the reinforcement and varying the weight fraction of the particles. Overall, It is observed that a gradual increase in the hardness value in sample-1(83
Jaiswal, Subham, Rajamurugan, Govindasamy, Krishnasamy, Prabu, Shaswat, Yashwardhan, Kaushik, Mishra
Low-Cost and Light-Weight Fireproof Material for Aircraft: Interior, Cargo Compartment and Unit Load Device (Fire and Explosion Container ULD)2019-01-18579/16/2019
Fire is a dramatic issue in aircraft nowadays, especially for composite air craft. An additional issue is the dangerous use of flammable Li-Ion batteries in many devices. To minimize fire issues, it is proposed to produce aircraft interiors, fire doors, cargo bay walls, and cargo containers that are able to contain a fire inside them, with our ceramic composite called TOUGHCERAM®. It is low-cost, ceramic, damage tolerant, and flexible between minus 100°C and plus 350°C. TOUGHCERAM® poly-crystalizes between 20°C and 110°C and can be reinforced with fibers (carbon or basalt). It will survive 90 minutes under direct contact with a propane torch of 1900°C. TOUGHCERAM® does not burn or smoke. This paper will explain how it is possible to develop a fully mineral-ceramic offering with unique mechanical, fire, and blast containment properties.
Sardou, Max
Ceramic Bound Materials: A Suitable Solution for Light Brakes2019-01-21099/15/2019
A ceramic bound matrix has been investigated to be used as a friction material. The materials were produced by means of ceramic technology using frits containing silicates, and ceramic friction modifiers such as tin oxide, zircon, iron oxide, magnesium oxide. Four formulations were tested by means of a tribometer (pin-on-disc tester) using a gray cast iron counterpart. Test section included speeds between 1 and 12 ms-1, and loads between 25 and 400 N. The coefficient of friction of the tested specimens were between 0.7 and 0.4, and exhibited sensitivity to speed at low loads (25 N), while they are quite stables at high loads (400N). The characterization of the tribolayers was carried out by means of scanning electron microscopy. The four developed materials were named A, B, C, and D. They exhibited different wear rates and coefficients of friction. All the materials exhibited sensitivity to speed, while showed a lower sensitivity to load. The coefficient of friction level seems to be
Dante, Roberto C., Cotilli, Edoardo, Conforti, Michael, Cotilli, Mario, Serrano-Posada, José Carlos, Schramm, Tobias, Ostermeyer, Georg-Peter, Dastrù, Marco
Heat Transfer Analysis of Catalytic Converters during Cold Starts2019-24-01639/9/2019
The transient heat transfer behavior of an automotive catalytic converter has been simulated with OpenFOAM in 1D. The model takes into consideration the gas-solid convective heat transfer, axial wall conduction and heat capacity effects in the solid phase, but also the chemical reactions of CO oxidation, based on simplified Arrhenius and Langmuir-Hinshelwood approaches. The associated parameters are the results of data in literature tuned by experiments. Simplified cases of constant flow rates and gas temperatures in the catalyst inflow have been chosen for a comprehensive analysis of the heat and mass transfer phenomena. The impact of inlet flow temperatures and inlet flow rates on the heat up characteristics as well as in the CO emissions have been quantified. A dimensional analysis is proposed and dimensionless temperature difference and space-time coordinates are introduced. Using this suitably modified coordinates, for the case of negligible axial solid conduction, computed solid
Papetti, Viola, Dimopoulos Eggenschwiler, Panayotis, Della Torre, Augusto, Montenegro, Gianluca, Onorati, Angelo, Koltsakis, Grigorios
Thermal Conductivities of Some Polymers and CompositesTBMG-348688/1/2019
Thermoset polymers are good electrical insulators that are used in applications ranging from electronics to composite armor. They are rather poor thermal conductors, however.
High-Temperature Dielectric NanocompositeTBMG-348998/1/2019
A nanocomposite was developed that could be a superior high-temperature dielectric material for flexible electronics, energy storage, and electric devices. The nanocomposite combines one-dimensional polymer nanofibers and two-dimensional boron nitride nano-sheets. The nanofibers reinforce the self-assembling material while the white graphene nanosheets provide a thermally conductive network that allows it to withstand the heat that breaks down common dielectrics, the polarized insulators in batteries, and other devices that separate positive and negative electrodes.
Thermal Conductivities of Some Polymers and Composites19AERP08_098/1/2019
Assessing the performance of polymers used in structural armor and filament winding applications. Army Research Laboratory, Aberdeen Proving Ground, Maryland Thermoset polymers are good electrical insulators that are used in applications ranging from electronics to composite armor. They are rather poor thermal conductors, however. For encapsulation of electronic components and devices, there is a huge amount of literature on filled polymers, particularly epoxies. One source provides a recent review of thermal conductivity (Kt) of filled polymers with emphasis on carbon nanotube loading. As an example of a low Kt polymer, a Kt of 0.3 watts per meter per degree kelvin (W/MK) for unfilled polyurethane from an unidentified source has been cited, with higher values for filled resin. Measurements have also been reported on particle-filled polypropylene with a neat resin Kt of 0.27 W/MK. These thermal conductivities are higher than those of most epoxies, and much lower than those of metals
Wristbands Do Health Check During WorkoutTBMG-345646/1/2019
Next-generation fitness sensors could give deeper insights into human health through noninvasive testing of bodily fluids. A stretchy patch developed at KAUST could help this approach by making it easier to analyze sweat for critical biomarkers.
Reliable Structures and Wearable Systems Call for Multiphysics SimulationTBMG-344425/1/2019
The increasing demand for miniaturized electronics and Internet of Things (IoT) devices has created new challenges for the specialists who design microdevices such as actuators, controllers, drivers, sensors, and transmitters. From responsive equipment and wearable monitors to energy efficient lighting in the office and automation in the factory, engineers need to bridge the microscopic components of semiconductors and our macroscopic world with reliable and innovative products. This shift has inspired engineers to find new solutions by exploring their ideas in the virtual world of numerical simulation.
Metallic Hollow Nanoparticle FabricationTBMG-341564/1/2019
NASA Langley Research Center has developed new methods for fabricating hollow nanoparticles using dendrimer molecules. Dendrimers are used as templates to control the size, stability, and solubility of these metallic nanoparticles ranging in metal lining thicknesses from less than 5 nm to several tens of nm.
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.
Process Developed to 3D Print Piezoelectric MaterialsTBMG-340223/1/2019
The piezoelectric materials that inhabit everything from our cell phones to musical greeting cards may be getting an upgrade thanks to work discussed in the journal Nature Materials. Xiaoyu “Rayne” Zheng, assistant professor of mechanical engineering in the College of Engineering and a member of the Macromolecules Innovation Institute, and his team have developed methods to 3D print piezoelectric materials that can be custom designed to convert movement, impact, and stress from any directions to electrical energy.
5 Ws of 3D-Printing Piezoelectric MaterialsTBMG-339203/1/2019
Piezoelectric materials are used in everything from cellphones and wearables, to robotics, energy harvesting, and tactile sensors.
Contaminant-Free SteelTBMG-336081/1/2019
For many highly stressed engineering applications like bearings and gears, contaminated steel parts can lead to devastating outcomes such as an emergency shutdown or the end of a mission. Ensuring that these critical components are as homogeneous as possible and free from porosity and other flaws is vital to performance, yet conventional steelmaking processes have multiple pathways of entry for unwanted contamination.
Alloy, Corrosion and Heat-Resistant, Sheet, Strip, and Plate 29Fe - 22Cr - 21Ni - 18.5Co - 3.2Mo - 2.8W - 0.78Ta - 0.30Al - 0.05Zr - 0.05La - 0.20N Solution Heat TreatedAMS5874C (Historical)10/10/2018
This specification covers a corrosion and heat-resistant alloy in the form of sheet, strip, and plate.
AMS F Corrosion Heat Resistant Alloys Committee
Alloy, Corrosion and Heat-Resistant, Sheet, Strip, and Plate 29Fe - 22Cr - 21Ni - 18.5Co - 3.2Mo - 2.8W - 0.78Ta - 0.30Al - 0.05Zr - 0.05La - 0.20N Solution Heat TreatedAMS5874C-TEST-REC (Historical)10/10/2018
This specification covers a corrosion and heat-resistant alloy in the form of sheet, strip, and plate.
AMS F Corrosion Heat Resistant Alloys Committee
High-Kinetic-Energy Penetrator Shielding and High-Wear-Resistance Materials Fabricated with Boron Nitride Nanotubes and BNNT Polymer CompositesTBMG-328319/1/2018
In recent years, anti-penetration materials have been more widely used for armor, bulletproof vests, and micrometeoroid and orbital debris protection layers for space-suits, space vehicles, and structures. Micrometeoroids develop very high kinetic energies as they travel through space, and pose a significant hazard to spacecraft and astronauts. The velocities of micrometeorites can reach 20 kilometers per second prior to impact on the lunar surface. Therefore, a new protective system utilizing new materials is needed to effectively shield the space vehicles and structures against the high-kinetic-energy penetrators as well as provide penetration-resistant spacesuits. In order to maximize the protection ability against high-kinetic-energy penetrators, the following two major material properties should be considered: high hardness for rebounding and/or gross mechanical deformation of the penetrator, and high toughness for effective energy absorption during the mechanical deformation (and
Coefficient of Thermal Expansion and Elastic Modulus of SIC P /AL 2 O 3 Ceramic Matrix Composites Prepared by Directed Metal Oxidation Process2018-28-00477/9/2018
The present paper, it is aimed to prepare SiCp/Al2O3 ceramic matrix composites using Directed Metal Oxidation process large enough dimension specimens for the measurement of physical properties. Continuous oxidation of an Aluminum alloy with suitable dopant along with a preform of SiC has lead to the formation of alumina matrix surrounding silicon carbide particulates. SiCp/Al2O3 ceramic matrix composites fabricated by the Directed Metal Oxidation process, possess required physical properties such as coefficient of thermal expansion (CTE) and elastic modulus, all at an affordable cost of fabrication. Al2O3 matrix composites reinforced with different volume fractions of SiC particulates were investigated for physical properties such as coefficient of thermal expansion (CTE) and elastic modulus. The composites with SiC volume fraction of 0.43 were found to possess a CTE as of as 5.0 x 10−6/K and an elastic modulus of 262 GPa.
Malkapuram, Dr Devaiah
Fabrication and Mechanical Properties of Alumina Nanoparticle Reinforced Magnesium Metal Matrix Composite by Stir Casting Method2018-28-00987/9/2018
In the present experimental investigation magnesium based alloy was prepared by mixing magnesium powder and aluminium powder in the ratio 65:35. The prepared magnesium alloy is used as the matrix material. Metal matrix composites were prepared by stir casting route. The composite was prepared by reinforcing 50 nm alumina nanoparticle so that the final composite contains 5, 10 and 15 wt.% alumina. Mechanical properties such as tensile strength, yield strength, impact strength and hardness were evaluated. Significant improvement was observed in impact strength and hardness value. The result showed that magnesium alloy with 5 wt.% alumina nanoparticle has a maximum impact strength of 25.2 J and hardness value 63.86 Hv respectively. Tensile strength and yield strength shows marginal increase in value.
T, Thirugnanasambandham, J, Chandradass, Sethupathi, P Baskara, Jesu Martin, Leenus
Applying an Electric Field May Lead to More Resilient Dental ImplantsTBMG-323887/1/2018
Researchers have observed a way that the brittle nature of ceramics can be overcome as they sustain heavy loads, leading to more resilient structures such as dental implants.
Products of Tomorrow: June 2018TBMG-290436/1/2018
This column presents technologies that have applications in commercial areas, possibly creating the products of tomorrow. To learn more about each technology, see the contact information provided for that innovation.
Experimental Evaluation of Transmission Loss-of-Lubrication TechnologiesF-0074-2018-128605/14/2018
ABSTRACT A Joint Aircraft Survivability Program (JASP) project was awarded in 2014 in order to accelerate the research and development on military helicopter transmission loss of lubrication survivability. This JASP project, "Helicopter Transmission Loss-of-Lubrication" was a collaboration between the US Army, US Navy, and NASA and completed in 2018. The approach for the effort was to first screen emerging technologies using coupon-level methods, then test those showing the most promise at the component level, and finally to downselect and evaluate these technologies at the system level. Several concepts to reduce heat generation, increase heat rejection, increase material tolerance to higher temperatures, and increase material resistance to damage were evaluated for this effort. Included in this evaluation were: a ceramic material for bearings, four different gear steels, various levels of gear surface roughness, six gear coatings, five lubricant and lubricant additive variations, and
Berkebile, Stephen, Colon-Rivera, Radames, Fetty, Jason, Murthy, Nikhil, Radil, Kevin, Dykas, Brian
High Temperature Ceramic Matrix Composite Materials Research for Next Generation Army Propulsion SystemF-0074-2018-128715/14/2018
ABSTRACT Aviation propulsion system structures are subjected to challenging conditions such as extremely high velocities, ultra-high/low temperatures, and excessive dust/sand/smoke/volcanic ash conditions during military operations. Therefore, the research and development of high-performance engine materials with superior characteristics such as great mechanical strength, high fatigue resistance and creep resistance, good tolerance to wide temperature variations, and excellent resistance to corrosion and oxidation is essential to the evolution of highly robust and efficient propulsion systems without a compromise on capabilities, even in hostile environments. The goal of this collaborative program within United States Army Research Laboratory (ARL) is to establish a generalized fundamental physics-based approach and probabilistic-based lifing method to extrapolate thermal loading performance and material characterization results from high performance high temperature ceramic materials
Ghoshal, Anindya, Mock, Clara, Murugan, Muthuvel, Nieto, Andy, Walock, Michael, Bravo, Luis, Pepi, Marc, Swab, Jeffrey, Hirsch, Samuel, Dowding, Robert
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.
Process Enables 3D Printing of Nanoscale Metal StructuresTBMG-287004/1/2018
In 3D printing — also known as additive manufacturing — an object is built layer-by-layer, allowing for the creation of structures that would be impossible to manufacture by conventional subtractive methods such as etching or milling.
Magnesium Alloy, Processes for Pretreatment and Prevention of Corrosion onAMSM3171 (Historical)2/25/2018
This specification covers general requirements for the apparatus, material, and procedures to be used in the processing of magnesium base alloys for the purpose of increasing their corrosion resistance and by producing surfaces suitable for organic paint finish systems.
AMS B Finishes Processes and Fluids Committee
Conductive, High-Toughness Oxides Deposited by Plasma Spray-Physical Vapor Deposition (PS-PVD)TBMG-283252/1/2018
Oxide coatings deposited in Glenn Research Center's Plasma Spray-Physical Vapor Deposition (PS-PVD) facility can be processed to be mechanically tough (erosion-resistant) and electrically conductive at room temperature. The electrically conductive phase contained within the oxide (MO2) coatings is a metastable suboxide (MO) that has not been formed in significant volume under any other known methods. Content of the electrically conductive phase can be varied in addition to the microstructure, which can be columnar, planar, or a combination of the two depending on the processing conditions. Upon exposing the material to moderate temperatures (>300 °C), the metastable phase is further oxidized (to MO2) and the material becomes insulating, but retains its high toughness and microstructure.
New Products & Services: December 2017 Aerospace Manufacturing & FabricationTBMG-2793912/1/2017
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