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Test Method for the Determination of Total Acidity in Polyol Ester and Diester Gas Turbine Lubricants by Automatic Potentiometric TitrationARP5088C (Current)11/26/2025
The test method describes the procedure for determination of the total acid number of new and degraded polyol ester and diester based gas turbine lubricants by potentiometric titration technique. The method was validated to cover an acidity range 0.05 to 6.0 mg KOH g-1. The method may also be suitable for the determination of acidities outside of this range and for other classes of lubricant.
E-34 Propulsion Lubricants Committee
Carbon Fiber Fabric and Epoxy Resin Wet Lay-Up Repair Material Part 5 - Carbon Fiber Fabrics, Plain Weave, 193 g/m2, and Epoxy ResinAMS2980/5A (Current)9/24/2021
This Material Specification defines the requirements of carbon fiber fabric and epoxy resin systems used for wet lay-up repair of carbon fiber reinforced epoxy structures, qualified according to AMS2980/1 and AMS2980/2. Unless otherwise specified by the drawing, the order or the inspection schedule, the present specification shall be used in conjunction with the referenced documents.
AMS CACRC Commercial Aircraft Composite Repair Committee
Automotive Safety Glazing MaterialsJ673_202107 (Current)7/16/2021
This SAE Recommended Practice is a guidance document, which covers current safety glazing materials applicable for use in motor vehicles and motor vehicle equipment. Nominal specifications for thickness, flatness, curvature, size, and fabrication details are included. This guidance document does not precede or replace customer specifications and requirements.
Glazing Materials Standards Committee
Bar, Rod, and Shapes Produced from 30% Glass Fiber Filled Polyamide-Imide (PAI) MaterialAMS3670/4D (Current)5/19/2021
This specification covers molded or extruded bar, rod, and shapes produced from a polyamide-imide (PAI) polymer filled with 30% glass fiber. This is designated as Grade 4 material per AMS3670.
AMS P Polymeric Materials Committee
Unidirectional Carbon Fiber Tape Epoxy Repair Prepreg, Vacuum Curing Part 5 - Material Specification for Unidirectional Carbon Fiber Tape Epoxy Prepreg for Repair and Film Adhesive for Repair, 120 to 145 °C (250 to 290 °F) CuringAMS6885/5 (Current)2/22/2021
AMS6885/5 is the Material Specification (MS) which defines the requirements of a unidirectional carbon fiber tape epoxy repair prepreg capable of curing under vacuum for repair of carbon fiber reinforced epoxy structures. It also defines the requirements of an epoxy film adhesive to be applied in a co-bonding process with the prepreg for solid laminate and sandwich bonding.
AMS CACRC Commercial Aircraft Composite Repair Committee
FITTING, PORT PLUG AND BLEEDERAS5169C (Historical)2/1/2021
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
Overlap Shear Test for Sealant Adhesive Bonding of Automotive Glass Encapsulating Material to Body OpeningJ1836_202101 (Current)1/7/2021
This recommended practice defines a procedure for the construction of a lap shear specimen for the purpose of testing the bondability of an automotive sealant adhesive to the elastomeric material used in automotive encapsulating. The present practice of encapsulating automotive glass is described as molding elastomeric material onto the outer edge of the glass using thermoplastic or thermosetting material that quickly sets in the mold. The glass is removed from the mold with cured elastomeric material bonded to the perimeter of thee glass. This encapsulated glass module can now be bonded with a sealant adhesive into the body opening of a vehicle.
Materials, Processes and Parts Council
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
Peel Adhesion Test for Glass to Elastomeric Material for Automotive Glass EncapsulationJ1907_202101 (Current)1/7/2021
This recommended practice defines a procedure for the construction and testing of a 180 deg peel specimen for the purpose of determining the bondability of glass to elastomeric material in automotive modular glass. This test method suggests that elastomeric material of less than 172 mpa modulus be used as the encapsulating material. The present practice of encapsulating automotive glass is described as molded-in-place elastomeric material onto the outer edge of the glass using thermoplastic or thermosetting material that quickly sets in the mold. The glass is removed from the mold with the cured elastomeric material bonded to the perimeter of the glass. This encapsulated glass module can now be bonded with a sealant adhesive into the body opening of a vehicle.
Materials, Processes and Parts Council
Carbon Fiber and Fiberglass Epoxy Prepreg Products with 350 °F (177 °C) Cure for Aerospace ApplicationsAMS6891 (Current)12/30/2020
The intent of this specification is for the procurement of carbon fiber and fiberglass epoxy prepreg products with 350 °F (177 °C) cure for aerospace applications; therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program must refer to the production quality assurance section (4.3) of this base specification, AMS6891.
AMS P17 Polymer Matrix Composites Committee
Carbon Fiber and Fiberglass Epoxy Prepreg Products with 350 °F (177 °C) Cure for Aerospace Applications: Type 35, Class 1, Grade 191AMS6891/1 (Current)12/29/2020
The intent of this specification is for the procurement of the material listed on the QPL; therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program must refer to the Quality Assurance section of this base specification, AMS6891.
AMS P17 Polymer Matrix Composites Committee
Carbon Fiber and Fiberglass Epoxy/Prepreg Products with 350 °F (177 °C) Cure for Aerospace Applications: Type 40, Class 1, Grade 196, Style 6K-PWAMS6891/2 (Current)12/29/2020
The intent of this specification is for the procurement of the material listed on the QPL; therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program must refer to the Quality Assurance section of this base specification, AMS6891.
AMS P17 Polymer Matrix Composites Committee
LEAD-FREE SOLDER VALIDATION TEST PLANUSCAR40-2 (Current)11/19/2020
This guideline is applicable to existing lead solder production products that will change to lead-free solder processes to meet the ELV Directive 2000/53/EC Annex II, exemption 8B requirements. This guideline is applicable to similar products used by multiple OEM's that have the same manufacturing processes / equipment. The intent is to streamline the supplier’s environmental testing via common qualification to reduce timing, quantities, and costs.
USCAR
Processing and Property Comparison of High-Temperature Carbon/BMI CompositesF-0076-2020-1634010/5/2020
Bismaleimide (BMI) resins are commonly used in advanced carbon composites for their high service temperature and excellent mechanical properties. In this study, two different BMI resins were compared: 1) formula RS-8HT, a high-cure temperature resin requiring pressurized consolidation, and 2) formula BMI-2, a lower cure temperature resin compatible with vacuum bag only fabrication. The objective was to identify a suitable high-temperature resin system for hybrid aerospace gear application, however, these materials are applicable to a variety of hot-zone parts. Laminates were fabricated from each resin type and characterized by their fiber volume fraction, compression strength vs. temperature, and glass transition temperature (Tg). Optical microscopy was performed to verify laminate quality. It was found that the carbon/RS-8HT laminates were prone to thermally-induced cracking, especially during post-cure. Carbon/BMI-2 laminates were found to attain a high degree of cure and high Tg from a realtively low temperature cure, without crack development. Additionally, the fiber volume fraction of the carbon/BMI-2 laminates, which were fabricated by a vacuum bag only process, were similar to that of the autoclave-processed carbon/RS-8HT laminates.
Waller, Matthew, Koudela, Kevin, McIntyre, Sean
Retainers (Backup Rings), Hydraulic and Pneumatic, Polytetrafluoroethylene Resin, Single Turn, Scarf-Cut, For Use in AS4716 GlandsAS5781B (Historical)8/25/2020
This SAE Aerospace Standard (AS) specifies scarf-cut polytetrafluoroethylene (PTFE) retainers (backup rings) for use in glands in accordance with AS4716. They are usually used in hydraulic and pneumatic system components as anti-extrusion devices in conjunction with O-rings and other seals for static and dynamic applications. NOTE: This specification includes material tests but does not include hydraulic or pneumatic performance tests.
A-6C2 Seals Committee
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.
Cable, Thermocouple Extension, Shielded and UnshieldedAS5419B (Current)6/2/2020
This SAE Aerospace Standard (AS) covers the requirements for thermocouple extension cable. Manufacturers of primary thermocouple wire in accordance with this specification must be qualified to the similar wire type specified in Table 1.
AE-8D Wire and Cable Committee
Hybrid Forming - A Novel Manufacturing Technique for Metal-LFT Structural Parts2020-01-02354/14/2020
Hybrid structural parts combining aluminum or steel sheets with long glass fiber reinforced thermoplastics (LFT) offer a great opportunity to reduce component weight for automotive applications. But due to high manufacturing cost, metal-LFT hybrid components are still scarcely used in automotive large-scale production. Thus in this work a novel cost- and time efficient manufacturing process for simultaneous metal sheet forming and compression molding of long fiber reinforced thermoplastics to manufacture automotive lightweight components is presented. In this manufacturing process, which is referred to as “Hybrid forming”, a fiber reinforced thermoplastic melt is used as a forming medium in the manner of well-known hydroforming processes. After forming the metal sheet by polymer melt in combination with the rigid die, the melt solidifies and forms a local reinforcement structure in the hybrid component. Since the metal sheet is pre-coated with a bonding agent prior to the forming process, a firmly bonded connection between metal and LFT can be achieved. For proof of concept a longitudinal control arm in a multi-link rear axle is chosen. By utilizing Hybrid forming a hybrid steel-LFT control arm is manufactured with weight savings of 20 % with regard to the metal reference component. Weight savings are derived by reducing the metal thickness and compensate stiffness and strength with local load-conforming LFT ribs. The metal part of the hybrid control arm guaranties the same positive fail-safe behavior of a metal component in contrast to the brittle failure mechanics of pure CFRP/GFRP components. To verify the resilience of the hybrid component and especially the bonding surface between steel and LFT quasi-static tests and fatigue tests were conducted. The results are compared with the FE-simulations to validate the simulation technique, which can be used to design metal-LFT structural parts manufactured by hybrid forming for future applications.
Heidrich, Daniel, Kloska, Tobias, Fang, Xiangfan
Effects of Helical Carbon Nanotubes on Mechanical Performance of Laminated Composites and Bonded Joints2020-01-00293/10/2020
Most composite assemblies and structures generally fail due to weak interlaminar properties and poor performance of their bonded joints that are assembled together with an adhesive layer. Adhesive failure and cohesive failure are among the most commonly observed failure modes in composite bonded joint assemblies. These failure modes occur due to the lack of reinforcement within the adhesive layer in transverse direction. In addition, the laminated composites fail due to the same reason that is the lack of reinforcement through the thickness direction between the laminae. The overall performance of any composite structures and assemblies largely depends on the interlaminar properties and the performance of its bonded joints. Various techniques and processes were developed in recent years to improve mechanical performance of the composite structures and assemblies, one of which includes the use of nanoscale reinforcements in between the laminae and within the adhesive layer. However, most prior research has been focused on use of straight carbon nanotubes (CNTs) and other nanomaterials in particle forms. The goal of this research was to improve the properties of the adhesive film and the interfacial bonding effectiveness between the laminae. Because CNTs are inert in nature, their interaction with the resin and adhesive polymer molecules is very weak. In this research we have used CNTs with various geometrical configuration (straight and helical geometries) and various weight percentages as additional reinforcements. The objective was to investigate the effectiveness of helical geometries of the CNTs to form interlocking mechanisms with the resin and the traditional microfiber reinforcements to improve the overall performance of the composite structures and assemblies. Single lap joint test specimens and flexural test specimens were prepared based on the ASTM standard D5868-01 and ASTM standard D790 and then tested and analyzed. The experimental results showed that the samples with CNT reinforcements performed considerably better than neat epoxy samples. Among the two different CNT geometries, helical CNTs performed better than the straight CNTs.
Sritharan, Ramanan, Askari, Davood
Researchers Develop Ultra-Thin, Ultra-Flexible Electronic MaterialTBMG-362753/1/2020
Researchers have developed an ultra-thin, ultra-flexible electronic material that could be printed and rolled out like newspaper. The material could be used for the touch-screens of the future. The touch-responsive technology is 100 times thinner than existing touchscreen materials and so pliable it can be rolled up like a tube.
Technique Creates Transparent Polythene Films as Strong as AluminumTBMG-359852/1/2020
Scientists replacing heavy and often brittle glasses with a transparent plastic previously used conventional transparent plastics like polycarbonate (PC) and poly(methylmethacrylate)(PMMA), both of which possess relatively unsatisfactory mechanical performance compared to an engineering material like aluminum. Current methods of creating high-strength plastic films such as hot-drawing of high-density polyethylene (HDPE) can lead to materials that can compete or even outperform traditional engineering materials like metals.
Sensing Applied Load and Damage Effects in Composites with Nondestructive TechniquesTBMG-3567212/1/2019
Composite materials are desirable for aeronautical and aerospace applications for many reasons including their high strength-to-weight ratios, fatigue and corrosion resistance, design adaptability, and performance capabilities in harsh environments. Because of these qualities, composites are useful in many applications such as in armor, helmets, and helicopters, and as structural components.
Sensing Applied Load and Damage Effects in Composites with Nondestructive Techniques19AERP12_0812/1/2019
Comparing and correlating piezoelectrically induced guided waves, acoustic emission, thermography, and X-ray imaging to determine the effects of applied load on a composite structure. Army Research Laboratory, Aberdeen Proving Ground, Maryland Composite materials are desirable for aeronautical and aerospace applications for many reasons including their high strength-to-weight ratios, fatigue and corrosion resistance, design adaptability, and performance capabilities in harsh environments. Because of these qualities, composites are useful in many applications such as in armor, helmets, and helicopters, and as structural components. However, when in-service, composite materials experience very different damage mechanics than metals. Performance and quality of composite materials can suffer from fatigue, environmental conditions, and external damage just as metals can, but due to their inherent complexity and the difficulty of detecting damage in composites with traditional inspection techniques, maintaining and guaranteeing the safety of composite structures is a challenging problem.
Novel Applications of Electrospinning Could Improve DevicesTBMG-3563612/1/2019
When you visit Andrew Steckl’s lab at the University of Cincinnati, you see a nondescript glass box that weaves together different fibers. He sees endless possibility.
Molecular Engineering for Mechanically Resilient and Stretchable Electronic Polymers and CompositesTBMG-3566412/1/2019
The ability to predict the mechanical properties of organic semiconductors is of critical importance for roll-to-roll production and thermomechanical reliability of organic electronic devices. This research describes the use of coarse-grained molecular dynamics simulations to predict the density, tensile modulus, Poisson ratio, and glass transition temperature for poly(3-hexylthiophene) (P3HT) and its blend with C60. In particular, it is shown that the resolution of the coarse-grained model has a strong effect on the predicted properties.
Molecular Engineering for Mechanically Resilient and Stretchable Electronic Polymers and Composites19AERP12_1012/1/2019
Establishing the design criteria for elasticity and ductility in conjugated polymers and composites by analysis of the structural determinants of the mechanical properties. Air Force Research Laboratory, Arlington, Virginia The ability to predict the mechanical properties of organic semiconductors is of critical importance for roll-to-roll production and thermomechanical reliability of organic electronic devices. This research describes the use of coarse-grained molecular dynamics simulations to predict the density, tensile modulus, Poisson ratio, and glass transition temperature for poly(3-hexylthiophene) (P3HT) and its blend with C60. In particular, it is shown that the resolution of the coarse-grained model has a strong effect on the predicted properties. It was found that a one-site model, in which each 3-hexylthiophene unit is represented by one coarse-grained bead, predicts significantly inaccurate values of density and tensile modulus. In contrast, a three-site model, with one coarse-grained bead for the thiophene ring and two for the hexyl chain, predicts values that are very close to experimental measurements (density = 0.955 g cm−3, tensile modulus = 1.23 GPa, Poisson ratio = 0.35, and glass transition temperature = 290 K). The model also correctly predicts the strain-induced alignment of chain, as well as the vitrification of P3HT by C60 and the corresponding increase in the tensile modulus (tensile modulus = 1.92 GPa, glass transition temperature = 310 K).
Embedded Fiber Optic Sensors (EFOS)TBMG-3569412/1/2019
Current laser interferometry pressure pulse detection techniques use the shock-induced change in index of refraction to track detonation and/or shock fronts in a single fiber optic by reflecting laser light off the boundary created between the unshocked material and the shocked material. This technique cannot be used in regimes where there isn't a strong enough shock front to reflect the laser light above the noise floor. Other embedded fiber techniques use a chirped fiber Bragg grating to track a shock position versus time by correlating a known spectrum of light to a calibrated position. These two systems use a single fiber and measure only time-of-arrival for a strong shock.
Development and Investigation of Jute/Linen Fibre Reinforced Polymer Composite2019-28-017110/11/2019
In recent automotive era, natural fibre reinforced with thermoset polymer composites have been incorporated by automotive industries especially for interiors, car body panels, dashboards, headliners etc. Natural fibres offer many affirmative qualities such as less weight and cost, especially in reduction of carbon di-oxide which is a major threat to the planet from the automotive sectors. The current work deals with the study of the potential usage of mineral powder (industrial by-product) in polymer. In this paper, hybrid composites with natural fabrics reinforcements and mineral powder as filler to matrix material are developed. The mineral powder used as filler is silica fumes which is a by-product of industries. The hand lay-up methodology is employed to fabricate the composite. The composites with and without mineral filler material are developed. The mechanical properties of the composites are assessed. The mechanical properties of composites with and without mineral filler are compared and their result shows that with addition of filler material, the mechanical properties of the composites are affected. Results disclose that loading of silica fumes increases the mechanical properties of the composite comparatively since it enhances the fibre matrix adhesion. Optical microscope & SEM are utilized to observe the composite’s morphology.
Pandian, Arvinda, Jailani, Siddhi
Analogy of Thermal Properties of Polyamide 6 Reinforced with Glass Fiber and Glass Beads through FDM Process2019-28-013710/11/2019
The essential target of this examination is to compare the morphological and thermal properties of two different polyamide composite blends with inventive thermal properties. The polyamide-6 (PA6) reinforced with 10, 20 and 30 wt. % glass fiber (GF) and PA6 reinforced with 10, 20 and 30 wt. % glass beads (GB) are the two different polyamide composite blends extruded in form of wire by twin screw extrusion process. The experimental study illustrates to print the specimens by means of Fusion Deposition Modeling (FDM) based Three-Dimensional (3D) printer. The responses like morphology, Thermal Conductivity (TC) and Heat Distortion Temperature (HDT) of composites were observed. From the scanning electron microscope (SEM) analysis equal distribution of higher 30wt% GF and GB in the PA6 matrix was observed. The results compare the increasing thermal properties of the 3D printed specimen like TC and HDT with the enhancement of beads content during the investigation. The GB are crystalline material which improves the thermal properties of the PA6 matrix and the GF are dimensionally stable material that can provide high modulus to the PA6 matrix. It was observed that, thermal property of neat PA6 matrix reinforced with 10, 20, 30 wt. % GB are comparatively higher than that of neat PA6 matrix reinforced with 10, 20, 30 wt. % GF. PA6+30% GB enhances the thermal properties and it may open new avenues for industrial applications like automotive, aerospace and electronics components.
Ranganathan, Soundararajan, Rangasamy Suguna Thangaraj, Hari Nishok, Vasudevan, Aravind Kumar, Shanmugan, Dharshan Karthick
Experimental Investigation on Mechanical Properties and Vibration Damping Frequency Factor of Kenaf Fiber Reinforced Epoxy Composite2019-28-016710/11/2019
Kenaf Fiber regarded as industrial crop for different applications. It is one of the most important plants cultivated for natural fibers globally. Natural fibers such as kenaf fibers are getting attention of researchers and industries to utilize it in different composites due to its biodegradable nature. In this present investigation mechanical properties, vibration damping frequency factor and thermogravimetric analysis of kenaf fiber reinforced epoxy composite (KFREC) have been evaluated and reported. The tests were conducted with different weight categories of kenaf fiber such as 20%, 25%, 30% and 35%. The effects of fiber content on tensile, flexural, impact strengths, hardness and thermal decomposition properties of the composite were determined. The failure mechanism and damage features of the KFREC were categorized using Scanning Electron Microscope (SEM). The results indicate that the increase in the fiber content decreases the damping vibration factor (ζ) correspondingly. The lowest value of the damping vibration factor was recorded as 0.033 for 35% weight content of Kenaf fiber in the composite. The maximum value of hardness, tensile, flexural, and impact strengths were noted as 447 BHN, 45.62 MPa, 124 kN and 13.2 J respectively and the effective thermal decomposition range was 378.64 - 442.18 °C for 35% of kenaf weight content KFREC. From the results it is identified that the kenaf fiber at 35% weight content reinforced with epoxy resin will be suitable for structural application in automobiles such as bumper beams, door panels and front modules. In addition to that the light weight nature of the kenaf fiber will help in achieving fuel economy in automobiles.
Rajamanickam, Sathish Kumar, Ravichandran, Vishnuvardhan, Sattanathan, Sivakumar, Ganapathy, Deenadayalan, Arockia Dhanraj, Joshuva
Design of Lightweight Composites for Vehicle Front End Energy Management of Bumper Beam2019-28-008510/11/2019
Application of advance composites in place of the various conventional materials such as steel can give significant weight and performance advantages. The application of composites is now finding it’s way in the automotive industry due to the growing requirement of the lightweight solutions and high strength to weight ratio. However, their low mechanical properties have limited their application in automotive structural components. The study presented here is focused on the explicit dynamic analysis of a bumper beam and advance composites are used for the study. Different configurations and designs of the bumper are considered to be able to make a comparative study of the stress and deformation levels. The analysis was done in coherence to the Euro NCAP tests and the offset frontal impact analysis was done. The boundary conditions were aligned with the real time impact conditions for proper prediction of the results. Based on stress, deformation, specific strength and weight, the replacing materials for existing steel bumper are considered and the corresponding energy absorption are calculated. Laminated composites such as Glass, Carbon and Hybrid composites are fabricated using Hand lay-up technique followed by Compression molding. The study reveals that we can match steel deflection using composite materials and reduce weight significantly.
Kumar, Praveen, Akella, Sarma Sr, Chakraborty, Ayan, Muthiah, Balasubramanian, Ramachandran, Velmurugan, M Venugopal, Shankar
Banana Stem Based Activated Carbon as Filler in Polymer Composites for Automobile Applications2019-28-009310/11/2019
Activated carbon was produced from a new part of banana plant namely true stem in this current research and used as fillers in polymer composites for automobile application. True stems of banana plants are the main wastes in banana or fruit markets which refer to the remains after banana fruits are removed from the supporting stems. Conversion of raw material into activated carbon particles is done by chemical and heat activation. The raw material used here were dried samples of banana plant’s true stem. This material was heated in a crucible at 400°C and then powdered. These crushed samples were activated using hydrochloric acid at 120°C for 5 hours and finally in a furnace for thermal activation at 700oC for 1 hour. These particles were incorporated as fillers in composites at Proportions of 15%, 25%, 35% and 45%. The activated carbon samples have been characterized by determining its fixed carbon content and bulk density. Scanning electron microscopy was done to analyze the morphology of particles. Mechanical tests were conducted for tensile strength, flexural strength and impact strength. It was observed that there was a decrease in tensile strength, toughness and impact properties as filler proportional percentage increased. The important novelty incorporated in this work is in the conversion of waste banana plant material into a valuable composite filler material for application in automobiles, which otherwise will go simply as scraps.
Ayyaswamy, John Presin Kumar, Sattanathan, Sivakumar, Ramachandran, Balaji, Nadarajan, Mukesh
3D-Printed Liquid Lab-on-a-ChipTBMG-3527910/1/2019
Researchers have 3D-printed an all-liquid device that, with the click of a button, can be repeatedly reconfigured on demand to serve a wide range of applications from making battery materials to screening drug candidates.
Atomically Thin Heat Shield Protects Electronic DevicesTBMG-3526610/1/2019
Excess heat given off by smartphones, laptops, and other electronic devices contributes to malfunctions and, in extreme cases, can even cause lithium batteries to explode. To guard against issues, engineers often insert glass, plastic, or layers of air as insulation to prevent heat-generating components like microprocessors from causing damage.
Clamp Material, Injection MoldedAIR1397B (Current)9/26/2019
This report presents the material properties and test requirements for an injection molded thermoplastic compound utilized for fabrication of AS1396 clamp block assembly.
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
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 and crystalline ceramics.
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.
Tuning Material Color and Thermal Properties SeparatelyTBMG-348988/1/2019
The color of a material can often tell how it handles heat. With clothing, for example, the darker the pigment, the warmer you're likely to feel on a hot day. Likewise, the more transparent a glass window, the more heat it can let through. A material's responses to visible and infrared radiation are often naturally linked.
A Penalization Method for 2D Ice Accretion Simulations2019-01-19396/10/2019
Numerical tools for 3D in-flight icing simulations are not straightforward to automate when seeking robustness and quality of the results. Difficulties arise from the geometry and mesh updates which need to be treated with care to avoid folding of the geometry, negative volumes or poor mesh quality. This paper aims at solving the mesh update issue by avoiding the re-meshing of the iced geometry. An immersed boundary method (here, penalization) is applied to a 2D ice accretion suite for multi-step icing simulations. The suggested approach starts from a standard body-fitted mesh, thus keeping the same solution for the first icing layer. Then, instead of updating the mesh, a penalization method is applied including: the detection of the immersed boundary, the penalization of the volume solvers to impose the boundary condition and the extraction of the surface data from the field solution. Although the current work is intended for 3D simulations, the content of this paper is limited to 2D applications to show the feasibility of the method. Tests are performed on multi-step rime and glaze ice cases where it is observed that the penalization method is able to produce sensible ice shapes compared to a body-fitted approach. However, accurate results are only achieved if the mesh is a priori refined in the zone where ice accretion is expected. The paper will further discuss the computational time, mesh refinement requirements, accuracy, limitations and recommendations for improvement of the penalization method applied to icing.
Lavoie, Pierre, Blanchard, Ghislain, Radenac, Emmanuel, Laurendeau, Eric, Villedieu, Philippe
Separating-Reattaching Flows Over an Iced Airfoil2019-01-19466/10/2019
Delayed Detached Eddy Simulations (DDES) of separating-reattaching flows on the suction side of an ice-contaminated airfoil were conducted. A single-section straight-wing NACA23012 airfoil with leading-edge ice was studied. The geometry represents a realistic glaze horn-ice contamination obtained during the icing test campaigns described in [1], which has aerodynamic data for comparison. The three-dimensional transient flow behavior was simulated using the open-source flow solver OVERFLOW, version 2.2l [2] developed by NASA Langley Research Center. Configurations at three angles of attack that exhibit unsteady flow behavior starting with the bursting angle were examined at Mach number of 0.18 and Reynolds number of 1.8x106. As the stall angle was approached the aerodynamic performance parameters displayed large-scale unsteadiness where periods of attached and separated flows were observed. The time-averaged results show good agreement with the aerodynamic test data. The calculated Strouhal number for the self-sustained low-frequency oscillations is consistent with the previous experimental research.
Oztekin, Ezgi, Riley, James
Modular Blocks Enable Plug-and-Play Diagnostic DevicesTBMG-346046/1/2019
Over the past decade, many researchers have been working on small, portable diagnostic devices based on chemical reactions that occur on paper strips. Many of these tests make use of lateral flow technology, which is the same approach used in home pregnancy tests.
A step-change in the cost of CFRP19AUTP05_035/1/2019
Williams Advanced Engineering reveals secrets behind its innovations aim to move carbon fiber into the mobility mainstream. A joke in the auto industry about CFRP (carbon fiber reinforced polymer) is that the “C” stands for “costly.” So, any manufacturing process that solves this significant drawback of the ultra-lightweight material's use outside of Formula One racing and exotic supercars, could change the vehicle-production game. Engineers at Williams Advanced Engineering in the U.K. are confident they have developed two complementary solutions to the cost hurdle. Revealing details of both, the company stated these solutions could be applied to high-volume production by 2021.
Birch, Stuart
Investigating Collaborative Robot Gripper Configurations for Simple Fabric Pick and Place Tasks2019-01-06994/2/2019
Fiber composite materials are widely used in many industrial applications - specially in automotive, aviation and consumer goods. Introducing light-weighting material solutions to reduce vehicle mass is driving innovative materials research activities as polymer composites offer high specific stiffness and strength compared to contemporary engineering materials. However, there are issues related to high production volume, automation strategies and handling methods. The state of the art for the production of these light-weight flexible textile or composite fiber products is setting up multi-stage manual operations for hand layups. Material handling of flexible textile/fiber components is a process bottleneck. Consequently, the long term research goal is to develop semi-automated pick and place processes for flexible materials utilizing collaborative robots within the process. Collaborative robots allow for interactive human-machine tasks to be conducted. The immediate research is to assess standard and modified grippers for basic material pick and place tasks via sets of experimental tasks. Pick and place experiments with flat carbon fiber fabric and two gripper configurations are tested with a YuMi 14000 ABB collaborative robot to determine the gripper characteristics and performance on the pickup, thread damage, material wrinkling, and slippage for two gripping forces, and two travel speeds. It is shown that using a silicone sleeve reduces the observed damage, material slippage, and wrinkling for most conditions.
Alebooyeh, Morteza, Wang, Bowen, Urbanic, Ruth Jill, Djuric, Ana, Kalami, Hamed
See-Through Film Rejects 70 Percent of Incoming Solar HeatTBMG-341664/1/2019
A heat-rejecting film was developed that could be applied to a building’s windows to reflect up to 70 percent of the Sun’s incoming heat. The film remains highly transparent below 32 °C (89 °F). Above that temperature, the film acts as an “autonomous system” to reject heat. If every exterior-facing window in a building were covered in this film, air conditioning and energy costs could drop by 10 percent.
FITTING, PORT PLUG AND BLEEDERAS5169B (Historical)3/28/2019
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
Characterization of Carbon Fiber and Glass Fiber’s Micro and Nanostructure Using Electron Microscopy, Raman Spectroscopy and XRD Analysis2019-01-14413/25/2019
Nowadays, most manufacturers are looking for the improvement of lightweight parts and other components in the automobile field. Carbon fiber and glass fiber are the most effective materials for their requirement to reduce the weight in vehicles due to their light weight and high tensile strength. The diameter of carbon fiber is 6 μm while glass fiber diameter is 17 μm. The mechanical tensile force of carbon fiber and glass fiber are 430 N and 290 N respectively on fiber alone without matrix. Carbon fibers are gradually smaller in each filament due to tensile force. Approximately 5 mm are elongated for both carbon fiber and glass fiber in tensile test report. In current research, characteristic and tensile force of carbon fiber and glass fiber were investigated by using electron microscopy, Raman spectroscopy and XRD.
Man, Tial Cuai, Karin, Preechar, Ohtake, Naoto, Aakasaka, Hiroki, Larpsuriyakul, Patcharee, Rojsatean, Jareenuch, Prakymoramas, Natcha, Thanomjitr, Dumrong, Kaewket, Sanya
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
Ferrofluid Technology Becomes a Magnet for Pioneering ArtistsTBMG-339413/1/2019
Spinoff is NASA's annual publication featuring successfully commercialized NASA technology. This commercialization has contributed to the development of products and services in the fields of health and medicine, consumer goods, transportation, public safety, computer technology, and environmental resources.
Numerical and Experimental Investigations on Flexural Fatigue Behaviour of Glass/Epoxy Composite and SAE 1040 Steel Tubes for Automotive Applications2019-26-03171/9/2019
Fatigue life of automotive structures depends on static strength, the range of stress, mode of cycling, load histories, and environmental conditions. i.e., temperature, humidity, moisture, etc. This paper presents results on the flexural fatigue life and damage accumulation of SAE 1040 steel and Glass/Epoxy composite automotive material tubes at room temperature in the dry condition. The correlation between their structure, geometry and fatigue behavior is a subject area that needs to be understood and investigated in the automotive applications like anti-roll bars and tubes. For comparative durability studies, the flexural static and fatigue tests were carried out on test specimens under constant amplitude with a sinusoidal waveform for a frequency of 3 Hz. Flexural fatigue loading conditions were analyzed at different load levels from 30% to 87% of the material ultimate flexural strength. Fatigue tests were stopped after 1 million cycles even if fracture or damage were not observed. Experimental S-N curves of SAE 1040 steel and Glass/Epoxy composite tube specimens were obtained under constant amplitude loading conditions. Fatigue properties obtained from specimen testing are then used in life predictions using the S-N approach. The predicted lives and damage evaluated from experimental and Finite Element codes using ANSYS software are found to be in good agreement. The fracture features of the steel and composite tubes observed with a Scanning Electron Microscope (SEM) were observed to agree with the obtained test data and predicted mechanism.
Bhanage, Amol, Krishnan, Padmanabhan
Researchers Map Light and Sound Wave Interactions in Optical FibersTBMG-335671/1/2019
Optical fibers make the Internet happen. They are fine threads of glass, as thin as a human hair, produced to transmit light. Optical fibers carry thousands of gigabits of data per second across the world and back. The same fibers also guide ultrasound waves, somewhat similar to those used in medical imaging.
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