Browse Topic: Foams

Items (249)

A Comprehensive Evaluation of PU Foam for EV NVH Performance

2025-01-012005/05/2023

Low density polyurethane foam was first proposed as an alternative to expandable baffles and tapes for sealing vehicle body cavities towards the end of the last century. In spite of several inherent advantages for cavity sealing, the high equipment cost of dispensing amongst other reasons, this technology has not spread as widely as expected. With the advent of electric vehicles, there is an increased emphasis on controlling higher frequencies from motors, inverters and other components, and polyurethane foam can be a viable solution by providing more robust sealing. Polyurethane foam sealing is already being employed in the new breed of electric vehicles but its NVH advantages have not been fully studied or published in literature. Using an existing electric vehicle with conventional expandable baffles & tape sealing measures, a comprehensive evaluation of NVH performance using the closed-cell polyurethane foam solution was carried out. Testing included component level bench test on

Kavarana, Farokh, Guertin, Bill, Braun, Arnold, Hand, Joshua, Thota, Manoj

Acoustic Evaluation of Fiber Based Materials for Engine Bay Applications

2025-01-011505/05/2023

A newly formulated fiber-based material was developed to offer a cleaner, recyclable alternative to foam-based vehicle acoustic products. The fiber-based material was designed to be used in multiple vehicle acoustic applications, with different blends of the material available depending on the application. It performs well as an engine bay sound absorber due to its high heat tolerance and good absorption performance. A study was conducted to evaluate the sound absorption performance of this fiber-based material, specifically the engine bay blends, in comparison to that of current foam-based products. The results from this study show that the sound absorption performance of this new fiber-based material can match that of current foam-based materials while providing a recyclable product unlike the foam.

Krugh, Jack

Impact of chemical blowing agent on polypropylene properties

2021-28-020310/01/2021

Weight reduction and material saving goals in automotive applications have led to the processing of thermoplastic polymers by foam injection molding. The density of the foamed polymer can be reduced up to 20%. Whilst, work has been reported on the weight reduction of the foamed polymer by using different types of blowing agent technologies, there has been limited studies in the areas of the sound transmission loss and material dampening properties of these materials. The present study is intended to understand the effect of chemical blowing agent (CBA) on the properties of polypropylene. The molded specimens were characterized against the density, Tensile property, flexural property, Izod impact, heat deflection temperature, differential scanning colorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infra-red spectroscopy (FT-IR), sound transmission loss (STL) properties as per standard test protocol and cell structures by stereo microscope. Obtained results indicates

Shukla, Sandeep Kumar, Balaji, K V

Test Method for Determining Cold Cracking of Flexible Plastic Materials

J323_202109 (Current)

09/15/2021

This SAE Recommended Practice is applicable for determining the cold characteristics of flexible plastic materials, as applicable. It consists of three different methods for determining low-temperature properties of materials depending on type of material and end use. The method used shall be as specified by the contractual parties.

Textile and Flexible Plastics Committee

Wearable, Stretchable Gas Sensor

TBMG-3850702/01/2021

A team has developed and tested a stretchable, wearable gas sensor for environmental sensing. It combines a newly developed laser-induced graphene foam material with a unique form of molybdenum disulfide and reduced-graphene oxide nanocomposites. The researchers were interested in seeing how different morphologies, or shapes, of the gas-sensitive nanocomposites affect the sensitivity of the material to detecting nitrogen dioxide molecules at very low concentration. To change the morphology, they packed a container with very finely ground salt crystals.

5 Ws of Algae-Based Flip-Flops

TBMG-3781010/01/2020

Flip-flops are one of the most popular sandals, with an estimated market size of $20 billion.

Hardening Lightweight Metal Foams with Nanocoating

TBMG-3581801/01/2020

Bones are strong and stable and can cope with loads almost as well as steel. But despite their strength, they are light enough to be easily moved by humans and animals. The secret lies in the combination of a hard, exterior shell that encases a porous lattice-like network of bone tissue in the interior of the bone. This structure saves on material and reduces weight.

Products of Tomorrow: December 2019

TBMG-3570712/01/2019

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.

Q&A: Professor Jaime Grunlan, Texas A&M University, College Station, TX

TBMG-3414104/01/2019

Professor Grunlan and his team are developing a new flame-retardant coating using renewable, nontoxic materials readily found in nature that could provide effective fire protection for several widely used materials.

Nanoscale Pillars Act as Memory Foam

TBMG-3393603/01/2019

A customizable nanomaterial was developed that combines metallic strength with a foam-like ability to compress and spring back. The material can store and release mechanical energy on the nanoscale, and fits into existing industrial semiconductor processes.

Artificial “Blubber” Protects Divers in Frigid Water

TBMG-3248208/01/2018

When Navy SEALs carry out dives in Arctic waters, or when rescue teams are diving under ice-covered rivers or ponds, the survival time even in the best wetsuits is very limited — as little as tens of minutes. Researchers have discovered a process to triple that survival time.

An Overview of Microstructural Approaches for Modelling and Improving Sound Proofing Properties of Cellular Foams: Developments and Prospects

2018-01-156406/13/2018

Significant advances have been made over the last 15 years in the field of modelling the acoustic properties of foams from the description of their microstructures. It entails a multidisciplinary work at the junction between physico-chemistry and mechanics of porous media, which involves a dialogue between different disciplines and requires the joint development of several techniques (imaging, upscaling, numerical computations, and experimental identification). It seems to be of timely interest to take stock of the methodological developments that have provided guidance on how to manufacture the new generation of foams with enhanced properties and to identify possible future methodological developments.

Perrot, Camille, Hoang, Minh Tan, Chevillotte, Fabien

Modeling the Effect of Foam Density and Strain Rate on the Compressive Response of Polyurethane Foams

05-11-02-001405/08/2018

Due to the high deformability and energy dissipation capacity of polymer foams in compression, they are used in automotive applications to mitigate mechanical impacts. The mechanical response of the foams is strongly affected by their density. Phenomenological relations have been proposed to describe the effect of foam density on their stress-strain response in compression at a fixed loading rate and the effect of loading rate at a fixed foam density. In the present work, these empirical approaches are combined allowing for the dependence of loading rate effect in compression on foam density. The minimum experimental data set for calibration of the proposed model consists of compression test results at two different loading rates of foams with two different densities. Rigid closed-cell polyurethane foams with apparent density in the range of ca. 100 to 300 kg/m3 have been produced and tested in compression up to a ca. 80% engineering strain at low (0.00167 to 0.5 s−1) and intermediate

Japins, Guntis, Kalnins, Kaspars, Kirpluks, Mikelis, Cabulis, Ugis

Magnesium Alloy, Processes for Pretreatment and Prevention of Corrosion on

AMSM3171 (Historical)02/25/2018

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

Advanced Carbon Aerogels for Energy Applications

TBMG-2830202/01/2018

Carbon aerogels (CAs) are nano-porous carbons comprising a particularly significant class of carbon nano-materials for a variety of sustainable energy applications. Carbon aerogels are specifically promising in that they possess a tunable, three-dimensional, hierarchical morphology with ultrafine cell size and an electrically conductive framework. They are available as macroscopic, centimeter-sized monolithic materials. Carbon aerogels hold great technological promise for a variety of sustainable energy applications including hydrogen and electrical energy storage, desalination, and electrocatalysis.

Aerospace & Defense Technology: December 2017

17AERP1212/01/2017

High-Reliability Capacitors When the Mission Just Can't Fail WIAMan High-Tech Test Lab Focuses on Saving Soldiers' Lives Improving the Surface Finish of Additive Manufactured Parts A new chemical immersion treatment could revolutionise the aerospace industry Using Thermoplastic Composites for Aerospace Applications Identifying and Isolating Signals Using Radio Frequency Photonics Bioinspired Surface Treatments for Improved Decontamination: Commercial Products Investigation seeks to determine which coatings shed fluids most effectively. Mechanical Characterization and Finite Element Implementation of the Soft Materials Used in a Novel Anthropometric Test Device for Simulating Underbody Blast Loading Understanding the mechanical behavior of components made from eight soft polymer materials is necessary to ensure the predictive capability of WIAMan FE models. Processing and Characterization of Lightweight Syntactic Materials Hollow spheres encapsulated in a metal matrix, syntactic metal

Functionally Graded Metal-Metal Composite Structures

TBMG-2770010/01/2017

NASA Langley Research Center has developed a functionally graded metal-metal composite structure. The structure is created using a method that avoids deleterious reactions between the different metal constituents, as would be observed via conventional melt processing. The results are unique alloy compositions and arrangements not typically available through conventional processing routes.

Contaminants for Aircraft Turbine Engine Fuel System Component Testing

AIR4246D (Current)09/27/2017

This SAE Aerospace Information Report (AIR) is intended as a guide toward standardization of descriptions and specifications of fluid contamination products.

AE-5B Aircraft and Engine Fuel and Lubricant Sys Components

Corrosion-Inhibiting Self-Expanding Foam

TBMG-2720107/01/2017

Surfaces such as metal and other corrodible surfaces are often exposed to extreme weathering, temperatures, moisture, impurities, and otherwise damaging external forces that accelerate corrosion. Conventional methods of corrosion protection include applying paints and other coatings, such as petroleum-based undercoatings, with a sprayer to the exposed surface. To be effective, the entire exposed surface must be covered or the corrosion process will be accelerated at the unprotected areas. While open-area surfaces may be easier to protect, those surfaces found in internal cavities within an overall framework can be more challenging to protect. Achieving full coverage on internal surfaces can be extremely difficult, and in some cases impossible without drilling several access openings in the structure. These extraneous openings can compromise the strength of the structure as well as create more entryways for water and debris. This increases the opportunity for corrosion to initiate at

Highly Porous and Mechanically Strong Ceramic Oxide Aerogels

TBMG-2683605/01/2017

NASA's Glenn Research Center (GRC) has developed and produced ultra-lightweight polymer cross-linked aerogels (X-Aerogels). These mechanically robust, highly porous, low-density materials are three times denser than native aerogels, but more than 100 times stronger. Aerogels are ultra-lightweight glass foams with extremely small pores (on the order of 10 to 50 nanometers). These materials are extremely good thermal insulators, with R values ranging from 2 to 10 times higher than polymer foams. Unlike multilayer insulation, aerogels do not require a high vacuum to maintain their low thermal conductivity, and can function as good thermal insulators at ambient pressure. In addition, they are good electrical insulators and have low refractive indices, both approaching values close to air. Aerogels are also excellent vibration-damping materials. Traditional aerogels, however, suffer fragility and poor environmental durability.

The Heavy Impact of Advanced Lightweight Materials

TBMG-2651403/01/2017

Historically, high-strength materials have been heavy and dense. The need for high-strength but lightweight materials has become more widespread when designing everything from vehicles and aircraft, to buildings and wind turbines. These advanced materials are enabling engines to operate efficiently at higher temperatures, use less fuel, and emit fewer pollutants, as well as finding uses in many other applications.

Aerofoam

TBMG-2601612/01/2016

Aerofoam is a unique foam composite insulation with improved thermal and acoustic insulation properties. The novelty of this invention comes from combining a polymer foam with a unique inorganic filler in a way that maximizes thermal performance while maintaining mechanical performance, chemical resistance, fire resistance, and acoustic insulation capabilities. The development of new manufacturing processes has also allowed for the development of these unique composite materials.

Potting Compound, Epoxy Bisphenol A-Type Syntactic Foam, Heat Cure

AMS3731/6C (Current)09/22/2016

This specification covers a glass or silica micosphere-filled epoxy resin formulation, supplied as a two-component system, requiring an oven cure for attainment of maximum properties.

AMS P Polymeric Materials Committee

Experimental Setup to Assess Blast and Penetration- Induced Secondary Debris in a Military Operations in Urban Terrain (MOUT) Environment

TBMG-2519808/01/2016

As part of Project Agreement on Military Operations in Urban Terrain (MOUT), the US Army Research Laboratory’s (ARL’s) Explosives Effects Branch supported a series of experiments conducted in Meppen, Germany (DEU), to understand loading on personnel protective equipment (PPE) produced during urban weapon attacks. These experiments were conducted by detonating an explosive charge placed on a brick wall to create secondary debris that would impact the US-designed collection medium.

Experimental Setup to Assess Blast and Penetration-Induced Secondary Debris in a Military Operations in Urban Terrain (MOUT) Environment

16AERP08_1208/01/2016

Testing demonstrates effects of blast debris on personnel protective equipment. Army Research Laboratory, Aberdeen Proving Ground, Maryland As part of Project Agreement on Military Operations in Urban Terrain (MOUT), the US Army Research Laboratory's (ARL's) Explosives Effects Branch supported a series of experiments conducted in Meppen, Germany (DEU), to understand loading on personnel protective equipment (PPE) produced during urban weapon attacks. These experiments were conducted by detonating an explosive charge placed on a brick wall to create secondary debris that would impact the US-designed collection medium. The experimental area consisted of 3 separate rooms (Figure 1). The first room was used as the blast room. The second and third rooms contained the collection medium. A double thick brick wall separated rooms 1 and 2 and was used to create the secondary debris.

Aluminoborosilicate Supplement for Thermal Protection of a Re-entrant Vehicle

TBMG-2496707/01/2016

The Toughened Uni-piece Fibrous Reinforced Oxidation-Resistant Com posite (TUFROC) allows for much more affordable and sustainable operations involving Space Launch Services and other systems that utilize Earth reentry vehicles. TUFROC has an exposed surface design and appropriate materials combination that will allow a space vehicle to survive both the mechanical stresses of the initial ascent, and the extreme heating and stress of re-entry. It provides a thermal protection tile attachment system that is suitable for application to a space vehicle leading edge, and for other uses in extreme heating environments (up to 3600 °F, and possibly higher, for short time intervals).

Aromatic Thermosetting coPolyester (ATSP) Composites for High-Temperature and Cryogenic Applications

TBMG-24964

07/01/2016

Advanced composite materials processable by cost-effective manufacturing play an important role in developing lightweight structures for future space and planetary exploration missions. With the growing demand for improved performance in the aerospace sector, advances in polymer systems with extreme thermomechanical properties are critical in providing excellent retention of performance in high-temperature environments, and high resistance to microcracking at cryogenic temperatures.

A Numerical Study of a Method for Estimating Sound Absorption Coefficient under a Synthesized Diffuse Acoustic Field

2016-01-184706/15/2016

A method for estimating the sound absorption coefficient of a material under a synthesized Diffuse Acoustic Field was recently proposed, as an alternative to classical sound absorption measurements in reverberant rooms (Robin O., Berry A., Doutres O., Atalla N., ‘Measurement of the absorption coefficient of absorbing materials under a synthesized diffuse acoustic field’, J. Acoust. Soc. Am., 136 (1) EL13-EL19, 2014). Using sound field reproduction approaches and a synthetic array of acoustic monopoles facing the material, estimation of the sound absorption coefficient under a reproduced Diffuse Acoustic Field in a hemi-anechoic room was shown to be feasible. The method was successfully tested on a few samples of melamine foam of close thicknesses and areas, but the influence of several parameters such as the source height, or the samples dimensions together with the nature of the porous material was not fully investigated. In this paper, the robustness of the method is numerically

Sgard, Franck, Doutres, Olivier, Robin, Olivier, Amedin, Celse Kafui, Berry, Alain, Atalla, Noureddine

Brake Insulator Damping Measurement Procedure

J3001_201604 (Current)

04/20/2016

This procedure is applicable to modes from 500 and 13,000 Hz. The parameters measured with this procedure are defined as the damping factor, ξ for first nine vibration modes of the beam. The measurement will be done in free-free conditions and with temperature.

Brake NVH Standards Committee

Flexible, High-Temperature Polyimide/Urea Aerogels

TBMG-2424804/01/2016

Cross-linked silica-based aerogels with polymeric materials, as well as incorporating a flexible linkage into the underlying metal oxide, have been proven to improve strength and resilience over their native, or non-cross-linked, counterparts without adversely affecting porosity and density. In this invention, high-temperature, stable, all-organic polyimide aerogels are prepared as reacting linear polyimide chains with a functional monomer to create branchings that are further room-temperature-cured with multifunctional isocyanate to form a three-dimensional network.

Deodorant, Aircraft Toilet

AMS1476C (Current)01/12/2016

This specification covers a biodegradable deodorant in the form of a liquid concentrate, solid, or gel.

AMS J Aircraft Maintenance Chemicals and Materials Committee

Sandwich Cores for the Future

TBMG-2356812/01/2015

by Bruce Morey

Sandwich cores for the future

15AERP12_0212/01/2015

Decreasing weight while increasing strength is always critical, from airliners to future space missions to Mars. Research in sandwich cores today may lead to radical improvements in the future. The search for lighter weight, stronger materials to construct airplanes and spacecraft remains as important as ever. But it takes a long time for new materials in aerospace structures to make their way into production designs. Capital is one reason; it is harder to take risks when it costs so much to develop new composites. Another is the long approval process from regulatory agencies due to safety constraints. “Aerospace is an interesting case because there is a lot that you can do with composites that is being done in [just] a few cases today,” explained Anthony Vicari, Lead Analyst for Advanced Materials for Lux Research, in an interview with Aerospace & Defense Technology.

Morey, Bruce

Smart MMOD Thermal Blanket

TBMG-23211

11/01/2015

This innovation provides for significantly improved protection from micrometeoroid and orbital debris (MMOD) particles, and reliably determines the location, depth, and extent of MMOD impact damage.

Aerogel-Filled Foam Core Insulation for Cryogenic Propellant Storage

TBMG-2320911/01/2015

Current cryogenic insulation materials suffer from various drawbacks including high cost and weight, lack of structural or load-bearing capability, fabrication complexity, and property anisotropy. A need clearly exists for lightweight thermal insulation that is isotropic and structurally capable with high thermal performance, while also offering reduced fabrication and installation complexity, and lower cost.

Lightweight Metal Foam Blocks Radiation

TBMG-2277808/19/2015

A strong, lightweight metal foam created by a North Carolina State University researcher absorbs the energy of high-impact collisions and effectively blocks X-rays, gamma rays, and neutron radiation. The device offers new shielding possibilities for use in CT scanners.

Modeling and Characterization of a Novel Porous Metallic Foam Inside Ducts

2015-01-220306/15/2015

A novel porous metallic foam has been studied in this work. This composite material is a mixture of resin and hollow spheres. It is lightweight, highly resistive to contamination and heat, and is capable of providing similar or better sound absorption compared to the conventional porous absorbers, but with a robust and less degradable properties. Several configurations of the material have been tested inside an expansion chamber with spatially periodic area changes. Bragg scattering was observed in some configurations with certain lattice constants. The acoustic properties of this material have been characterized from the measurement of the two-port matrix across a cylindrical sample. The complex density and speed of sound can be extracted from the transfer matrix using an optimization technique. Several models were developed to validate the effect of this metallic foam using Finite Elements and the Two-port Theory. There was a good agreement between both models and the measurement

Farooqui, Maaz, Elnady, Tamer, Glav, Ragnar, Karlsson, Tony

The Use of Intumescent Coatings with Polymer Composites for High Temperature Automotive Applications

2015-01-071304/14/2015

To meet corporate CO2 emission targets polymer composites are being explored for light-weighting vehicle applications. Operational requirements may demand that such materials function above glass transition temperatures or heat deflection points. Intumescent coatings are traditionally used in construction to protect steelwork during fire. This paper presents a novel experimental investigation of two intumescent technologies to thermally protect a reinforced polyamide, for use as a semi-structural vehicle component. Coatings were assessed against the thermal requirement to withstand 500°C for 10 minutes. The differences in performance observed between water and epoxy based coatings as well as when an insulation layer was introduced are reported. Ultimate Tensile Stress (UTS) and modulus values were obtained at −40°C, ambient, and 85°C for uncoated specimens before and after thermal cycling. Results indicated although samples did not surpass the heat deflection point of the material (220

Simmonds, Helena, Cox, Sophie, Nicholls, Steve, Williams, Geraint

Toughened Uni-piece Fibrous Reinforced Oxidation-Resistant Composite (TUFROC)

TBMG-2051709/01/2014

TUFROC has an exposed surface edge design and an appropriate materials combination for a space vehicle that will survive the mechanical stresses induced in the initial ascent, and will subsequently survive the extreme heating and mechanically stressful environment of re-entry. It provides a thermal protection tile attachment system, suitable for application to a space vehicle leading edge, and for other uses in extreme heating environments [up to 3,600 °F (1,982 °C), and possibly higher, for short time intervals].

Preventing Fatal Blood Loss with Injectable Foam

TBMG-2015909/01/2014

In a combat situation, a wounded soldier can bleed to death quickly without prompt attention. But depending on where the injury is, like a deep wound at the neck, shoulder, or groin, traditional treatments, such as tourniquets, may not be able to staunch the blood loss. So, engineering students at Johns Hopkins University, Baltimore, MD, invented an injectable foam system designed to quickly stop this type of profuse bleeding. The invention is designed to apply pressure and curb blood loss during the critical first hour during which a wounded soldier can be moved to a site for more advanced medical help.

Dr. Mary Ann Meador, Senior Research Scientist, Glenn Research Center, Cleveland, OH

TBMG-2005406/24/2014

Dr. Mary Ann Meador, Senior Research Scientist at NASA Glenn Research Center, guides projects that will synthesize new types of aerogels. Her research has focused on the design and development of new polymers for a variety of applications, including high-temperature composites.

Dispersion of Carbon Nanotubes Into Polymer Matrices to Produce Unique Properties

TBMG-19372

04/01/2014

The present invention addresses the effective dispersion of carbon nanotubes (CNTs) into polymer matrices. The nanocomposites are prepared using polymer matrices and exhibit a unique combination of properties, most notably, high retention of optical transparency in the visible range (i.e., 400 to 800 nm), electrical conductivity, and high thermal stability.

Sandwich Panels with Corrugated Core - A Lightweighting Concept with Improved Stiffness

2014-01-080804/01/2014

Sandwich panels with high modulus/high strength skin material and low density/low modulus core material have higher stiffness-to-weight ratio than monolithic panels. In this paper, sandwich panels with corrugated core are explored as a lightweighting concept for improved stiffness. The skin and the core materials are a high strength steel, aluminum alloy or carbon fiber-epoxy composite. The core has a triangular corrugation, a trapezoidal corrugation and a rectangular corrugation. The stiffness of the sandwich panels is analytically determined and compared with monolithic panels of equal mass. It is shown that the stiffness of the sandwich panels is 5 to 7 times higher than that of the monolithic panels.

Mallick, Pankaj K., Boorle, Rajesh

Using Molded Foam Makes Assembly a Snap

TBMG-19047

02/01/2014

Today, medical devices are made using a variety of plastic materials and manufacturing processes. Advances in plastic processing make it possible to obtain virtually any shape, form, or function. In addition, the vast assortment of plastics available allows designers to design for the optimal balance of functionality, performance, and cost. Expanded polypropylene (EPP) is a plastic material that is starting to gain traction in the medical device market as product designers become more familiar with the multiple benefits it can provide.