Browse Topic: Drying

Items (105)

Polishing Compound, Aircraft Metal

AMS1650D (Current)

05/06/2021

This specification covers a polishing compound for aircraft metals in the form of a liquid or paste.

AMS J Aircraft Maintenance Chemicals and Materials Committee

Wafer-Scale Membrane Release Process

TBMG-3847602/01/2021

Precise measurements utilizing sensitive instruments may require thermally managed detectors; therefore, thermal insulation of the detector is essential to its performance. To maintain critical signal-to-noise ratio, there is a need for larger thermal isolation structures. Due to high detector filling fraction limits, these isolation structures may be thinner, less mechanically robust, and more prone to breakage during fabrication.

Manufacturing Technique Helps Inkjet Printers Deliver Ink More Evenly

TBMG-3370802/01/2019

When a coffee mug leaves a ring, the outer edges of that ring are darker than the inside of the ring. That's because the solute is separated from the liquid during the evaporation process — the coffee ring effect. This same effect can happen with printers. When printing a text document, the text itself consists of an outline of the letters and the inside of the letters. While it may not be visible to the untrained eye, the outlines are actually darker than the inside. This happens during the drying process, just like the coffee ring effect. Efforts have been made to find a way to remove this difference in pigmentation.

Adam Sidor, NASA Research Fellow, Georgia Institute of Technology, Atlanta, GA

TBMG-2710206/20/2017

Thermal Protection Systems (TPS) — heatshields — form the outer surface of spacecraft and provide protection as the vehicle plunges through planetary atmospheres. Conformal ablative materials are currently being developed to improve TPS performance. Adam Sidor is developing a fresh approach to designing and manufacturing these materials to produce larger tile sizes while reducing labor, cost, and waste.

The Effects of Cure Schedule on Water-Based LASD Loss Factor and Implications for Prototype Testing

2017-01-185406/05/2017

Liquid applied sound deadener (LASD) is a light-weight, targeted vibration damping treatment traditionally used in the automotive market for body-in-white (BIW) panels. Water-based LASDs may cure over a wide range of conditions from room temperature to over 200°C. However, curing conditions commonly affect change in the damping characteristics. A thorough understanding of the relationship between curing conditions and subsequent damping performances will inform the material selection process and may allow pre-manufacturing designs to be adjusted with limited impact during validation. This paper aims to strengthen the quantitative understanding of the role LASD curing conditions have on damping performance by observing the effects of variations in thickness and cure temperature as measured by the Oberst method. Additionally, this paper proposes a simple approach to using LASD treatments of equivalent damping loss factor to approximate heat-cure LASD performance with room temperature

Anton, John T., Ley, Jason, Grover, Ikpreet S., Stotera, David

Insulating Materials and Precursor Formulations, and Method of Forming

02/01/2015

Methods were developed for forming an insulating material that combines a polysilazane, a cross-linking compound, and a gas-generating compound to form a reaction mixture, and curing the reaction mixture to form a modified polysilazane. The gas-generating compound may be water, an alcohol, an amine, or a matrix comprising one of a reaction product of a polysilazane and an isocyanate, and a reaction product of a polysilazane and an epoxy resin. The matrix also comprises a plurality of interconnected pores produced from a reaction of the polysilazane and the epoxy resin.

TBMG-2100811/01/2014

DELO (Windach, Germany) now offers a new, high-intensity LED spot lamp with a wavelength of 400 nm. The DELOLUX 50 allows for fast, reliable, pinpoint curing of adhesive layers with thicknesses up to 10 mm, making it suitable for transmission through plastics like polymethylmethacrylate (PMMA), polycarbonate (PC) or polyamide (PA). The lamp’s LED heads are available in two variants with an emission spectrum of 365 nm and 400 nm. Because of the two variants, the DELOLUX 50 easily cures UV- and light-curing adhesives, regardless of whether components need to be fixed in less than one second with 365 nm or deep cured with 400 nm.

Room Temperature Curing Thermally Conductive Epoxy For Service Up To 400°F

1167104/01/2013

Master Bond Polymer System EP21TCHT-1 is a two component, thermally conductive, heat resistant epoxy compound formulated to cure at ambient temperatures or more rapidly at elevated temperatures. EP21TCHT-1 passes NASA low outgassing tests and develops a high bonding strength of 1,800 psi at ambient temperatures.

Benefits of LED Cured Adhesives in Medical Applications

TBMG-1512911/01/2012

Selecting an adhesive is often a difficult task because it involves give and take between the end-use and manufacturing requirements. When it comes to bonding applications in the medical industry, the challenge is even greater because of strict specifications and safety constraints. A common standard for adhesives in medical devices is biocompatibility. In North America, the most widely accepted test for biocompatibility is United States Pharm acopeia (USP) Class VI. In tended to evaluate the suitability of polymeric materials for direct and indirect patient contact, the USP Class VI regimen consists of a series of in vivo reactivity and toxicity tests. These tests involve injecting and implanting samples of the material under consideration into mice and rabbits, which are then evaluated at fixed time intervals for any ill effects. ISO 10993 is another standard that tests cytotoxicity and is used to determine an adhesive’s compatibility with blood and body fluids according to the

Cutting Tool Technology for Machining Composite Curing Tools

2012-01-187509/10/2012

In the present study, a fully controlled experimental protocol is used to investigate the difference in milling Invar and HexTool® for composites curing tools. The main difference is the use of the different strategies: conventional milling is better than climb milling, high feed/low speed better than low feed/high speed, high depth of cut better than low depth of cut, air coolant better than water coolant, diamond coating better than solid carbide, sand finishing better than chip removal, torus tools better than ball nose tools. Therefore, using metal machining strategy on composite curing tools leads to cracking and delaminations in the composite surface which causes the resin flow to infiltrate these cracks during the molding process. Consequently, parts demolding will destroy the surface of the curing tool and make it unusable without repair. The new technology approach will lead to a higher integrity of the composite surface and enhance the life cycle of the curing tool.

Mueller-Hummel, Peter

Silk Microneedles Deliver Controlled-Release Drugs Painlessly

TBMG-1463309/01/2012

Bioengineers have developed a new silk-based microneedle system able to deliver precise amounts of drugs over time and without need for refrigeration. The tiny needles can be fabricated under normal temperature and pressure and from water, so they can be loaded with sensitive biochemical compounds and maintain their activity prior to use. They are also biodegradable and biocompatible.

Sensors Enable Precision Mounting of X-Ray Optics

TBMG-1414207/01/2012

NASA is developing the next generation of X-ray optics that could be used in an orbiting X-Ray Observatory. The “lens” consists of thousands of mirrors positioned to reflect X-rays at a shallow angle at focal length of 3-10 meters. Locating and fixing the mirrors in position is the primary challenge of the project. Creating focus at the long focal lengths requires a mirror angular position tolerance of only 1 μRadian, and the precisely shaped mirrors, when mounted, must distort less than 0.1 μm from their free, unmounted state. Any such assembly must be able to hold these positions through launch and deployment.

Sealing Materials for Use in Vacuum at High Temperatures

TBMG-1304403/01/2012

Sealing materials that can be applied and left in place in vacuum over a wide range of temperatures (especially temperatures of a few thousand degrees Celsius) have been conceived and investigated for potential utility in repairing thermal-protection tiles on the space shuttles in orbit before returning to Earth. These materials are also adaptable to numerous terrestrial applications that involve vacuum processing and/or repair of structures that must withstand high temperatures. These materials can be formulated to have mechanical handling characteristics ranging from almost freely flowing liquid- like consistency through paste-like consistency to stiff putty-like consistency, and to retain these characteristics in vacuum until heated to high curing temperatures.

Advantages of Manufacturing Silicone Drug-Eluting Components via Ultraviolet Light Vulcanization Process

TBMG-1281702/01/2012

Combination products offer several advantages when compared with drug delivery via oral, injection, and infusion methods. All drug-device type combination products exhibit one or more of the following attributes. First, they provide controlled release of the active pharmaceutical ingredients (API) instead of bolus-type delivery; API concentrations can be consistently maintained within an optimal therapeutic range. Second, drug-eluting devices, particularly implanted devices, allow for a targeted delivery of the API. This targeted approach, when contrasted with systemic administration, permits higher therapeutic dosages to be delivered while minimizing adverse side effects. Third, combination products have been shown to improve patient compliance. Most healthcare practitioners now agree that within our aging population, compliance becomes less certain and therefore more important.

Controlling Heat Curing Adhesive Processes Using Infrared Spot Curing

TBMG-1266301/01/2012

Adhesives are often used as the joining compound between substrates in the medical device industry. Typical applications for adhesives include tube-to-connector bonding, steel-cannula-to-hub bonding, and any other joining process. Adhesives work particularly well in the assembly of dissimilar materials where traditional solvent-welding methods are being eliminated due to workplace safety legislation and where other joining methods such as ultrasonic welding and laser welding are inadequate.

Taking the Heat: Silicone’s Unique Properties Help Create the Next Generation of LED Lighting

TBMG-1427811/01/2011

As global energy demand rises, the significant energy-saving potential of light-emitting diode (LED) lighting remains a top consideration for lighting manufacturers as well as designers, architects, and consultants looking to offer clients more sustainable options. LED lighting uses one-tenth the power of standard incandescent lighting and lasts 25 times longer — it even has the long-term potential to produce more light, with less cost, than compact fluorescent lamps, or CFLs. In fact, LED lighting may soon replace most lighting in homes, offices, public spaces, and in many other applications.

A Study on the Low-Weigt BMC for Headlamp Reflector

2011-28-001010/06/2011

Optimal Composition of Light-weight BMC (Bulk molding compound) for automotive headlamp reflector using Glass bubble was investigated. Glass bubble (G/B) normally has low heat conductivity which has a bad influence on cycle time making products like reflectors. It was very important to improve the productivity of Light-weight BMC by means of finding optimal composition of base resin, curing agent and other additives. This study focused on the ideal ratio of each component of BMC, unsaturated polyester resin, glass bubble, inorganic filler, glass fiber and additives. Mechanical and environmental properties of the product which was made of optimized light-weight BMC were evaluated to compare with the properties of the product which was made of existing BMC.

Kim, Yawon, Lee, Junghwan, Kim, Ok, Chun, Yong

Effect of Coating and Drying Process on Electrode Structure and Performance

TP-AAB-AABC_EUROPE_2011_1006/11/2011

iPAT presentation of "Effect of Coating and Drying Process on Electrode Structure and Performance" for AABC Europe 2011.

Kwade, Arno, Haselrieder, Wolfgang

Mount Protects Thin-Walled Glass or Ceramic Tubes From Large Thermal and Vibration Loads

TBMG-943603/01/2011

The design allows for the low-stress mounting of fragile objects, like thin walled glass, by using particular ways of compensating, isolating, or releasing the coefficient of thermal expansion (CTE) differences between the mounted object and the mount itself. This mount profile is lower than true full kinematic mounting. Also, this approach enables accurate positioning of the component for electrical and optical interfaces. It avoids the higher and unpredictable stress issues that often result from “potting” the object. The mount has been built and tested to space-flight specifications, and has been used for fiber-optic, optical, and electrical interfaces for a spaceflight mission.

Process for Making a Noble Metal on Tin Oxide Catalyst

TBMG-890112/01/2010

To produce a noble metal-on-metal oxide catalyst on an inert, high-surface-area support material (that functions as a catalyst at approximately room temperature using chloride-free reagents), for use in a carbon dioxide laser, requires two steps: First, a commercially available, inert, high-surface area support material (silica spheres) is coated with a thin layer of metal oxide, a monolayer equivalent. Very beneficial results have been obtained using nitric acid as an oxidizing agent because it leaves no residue. It is also helpful if the spheres are first de-aerated by boiling in water to allow the entire surface to be coated. A metal, such as tin, is then dissolved in the oxidizing agent/support material mixture to yield, in the case of tin, metastannic acid. Although tin has proven especially beneficial for use in a closed-cycle CO2 laser, in general any metal with two valence states, such as most transition metals and antimony, may be used. The metastannic acid will be adsorbed

Repeatable, Low-Cost UV Assembly of Biosensors

TBMG-875611/01/2010

A biosensor is an analytical device that converts a biological response into an electrical signal. It is increasingly being used as a cost-effective diagnostic tool that offers the capability to render efficient, easy-to-use, and accurate diagnosis. While technological advances in biosensors are allowing this technology to cater to an extensive range of applications in a number of fields, such as industrial and environmental testing, the largest applications have been in the healthcare sector, including glucose detection, pregnancy testing, blood testing, breath analyzers, and cancer diagnosis.

Effect of Drying Methods on the Physical and Structural Changes in Oil-Seed Flax Fiber

2010-01-202410/05/2010

With the growing environmental concerns, biodegradable materials are gaining more importance. Biocomposites which are made from a combination of biological fiber such as flax and hemp together with plastics are finding a good number of applications in day to day life. Flax has good physical and mechanical properties that can be utilized in areas like construction, biomedical & bioproducts and electronics applications. The quality of fiber depends upon various unit operations used in the processing. Drying is one of the most important unit operations which significantly affect the quality of the fiber. The method of drying for removal of moisture from the fiber significantly affects the drying time and quality. In the present study the raw flax fiber was subjected to drying before and after chemical treatment. The physical properties such as; tensile strength, color and structural changes were measured for raw and chemically treated flax fibers. The diameter range was in-between 30-300

Tripathy, Anand C.

Carbon-Nanotube-Based Chemical Gas Sensor

TBMG-861310/01/2010

Conventional thermal conductivity gauges (e.g. Pirani gauges) lend themselves to applications such as leak detectors, or in gas chromatographs for identifying various gas species. However, these conventional gauges are physically large, operate at high power, and have a slow response time.

Functionalization of Single-Wall Carbon Nanotubes by Photo-Oxidation

TBMG-848909/01/2010

A new technique for carbon nanotube oxidation was developed based upon the photo-oxidation of organic compounds. The resulting method is more benign than conventional oxidation approaches and produces single-wall carbon nanotubes (SWCNTs) with higher levels of oxidation.

Hybrid AlGaN-SiC Avalanche Photodiode for Deep-UV Photon Detection

TBMG-1051209/01/2010

NASA’s Goddard Space Flight Center, Greenbelt, Maryland

Fire Resistance of Geopolymer Concretes

TBMG-826108/01/2010

Geopolymer concrete has been proposed as an alternative to Portland cement concrete in applications requiring high degrees of fire resistance, because the intrinsic chemistry of the geopolymer binder does not require the retention of water or hydration within gel phases to maintain structural integrity of the binder. Portland cement concrete contains a high level of chemically bound water, which is essential to the gel binder structure, and which is lost upon heating to several hundred degrees Celsius, whereas the water present within a geopolymer concrete is overwhelmingly present in pores and is not an essential part of the strength-generating phases. However, predictions of geopolymer concrete fire performance have up to this time been based on small-scale laboratory testing (usually on paste or mortar specimens), rather than the study of large concrete sections, which provides significance to this work.

Biotic-Abiotic Interface Between the Body and an Artificial Limb

TBMG-787605/01/2010

Because of its high mechanical properties, chemical stability, and biocompatibility, titanium is a commonly used material in dental and orthopedic applications. Its excellent biocompatibility allows titanium implants to be directly anchored to bone, or osseo-integrated. The conventional prosthetic replacement in amputees is a stump-socket design, which transfers forces through the prosthetic to an external contact point on the patient. Such a design results in non-uniform distribution of pressure, and can lead to pain, infection, and necrosis of the soft tissues at the point of contact.

Advances in out-of-autoclave

10AEMD0303_0103/03/2010

As carbon-fiber composites continue to gain weight share on modern aircraft, reducing the need for autoclave cures becomes more important. High-performance carbon fiber-reinforced plastic (CFRP) parts in aerospace applications have come of age in aerospace. CFRP means better fuel efficiency as well as manufacturing efficiency. For example, half of the weight of the new Boeing 787 is from CFRP composites. The demands of flight require a robust, uniform, strong, and tough material. Composite parts are formed in a number of ways-hand layup, automated tape layers, automatic fiber placement, closed mold methods such as Resin Transfer Molding (RTM), or pultrusion to name just a few, noted Dr. Bert Erdel, Executive Technology Advisor for Morris Group.

UV LED Spot Curing System

TBMG-1438503/01/2010

EXFO's Life Sciences & Industrial Division, Mississauga, ON, Canada, introduces the OmniCure® LX400 UV LED Spot Curing System. The system is able to control up to four UV LED heads simultaneously with a single connection or independently. UV LED heads are available in three different wavelengths (365nm, 385nm, and 400nm) for greater compatibility with current adhesives. Each head can be set for different exposure times and irradiance levels in 1% increments. The system is ideal for UV spot curing assembly processes used in manufacturing optical communication, lenses, DVDs, and electronic equipment. www.EXFO-OmniCure.com

Vibrating Quartz Sensor Characterizes Liquid Samples

TBMG-659601/01/2010

A novel analytical technology characterizes liquids for healthcare applications. As a drop of liquid evaporates on a vibrating quartz sensor, it undergoes distinctive phase changes representing the unique chemical and physical characteristics of the sample. This unique “fingerprint” represents information that is not readily available from any combination of analytical methods currently in use.

Extended Shelf Life for PMR Polyimide Resins and Prepregs

TBMG-693701/01/2010

An improved class of formulations for PMR polyimide resins retards the imidization that undesirably occurs during handling and storage. While imidization is desired at the final (deliberate polymerization) stage of production of a polyimide, imidization results in premature aging when it occurs during earlier stages of synthesis, shipping, prepregging, and fabrication layup. By retarding imidization at storage and handling temperatures, the improved class of formulations increases both shelf life and the upper limit of allowable temperature for handling and storage prior to final polymerization.

Silica-Filled EPDM Rubbers as Ablative Insulating Materials

TBMG-697401/01/2010

Silica-filled polymers made from ethylene propylene diene monomer (EPDM) have been found to be useful as ablative thermal-insulation materials. These polymers have been investigated as candidates to replace some previously developed polymeric ablative rocket-engine insulating materials that will soon become commercially unavailable. Although these materials have been developed specifically for use in and on solid-fuel rocket motors, they may also be useful in terrestrial applications in which there are requirements for protection against high temperatures for short times.

Gratings Fabricated on Flat Surfaces and Reproduced on Non-Flat Substrates

TBMG-636212/01/2009

A method has been developed for fabricating gratings on flat substrates, and then reproducing the groove pattern on a curved (concave or convex) substrate and a corresponding grating device. First, surface relief diffraction grating grooves are formed on flat substrates. For example, they may be fabricated using photolithography and reactive ion etching, maskless lithography, holography, or mechanical ruling. Then, an imprint of the grating is made on a deformable substrate, such as plastic, polymer, or other materials using thermoforming, hot or cold embossing, or other methods. Interim stamps using electroforming, or other methods, may be produced for the imprinting process or if the same polarity of the grating image is required. The imprinted, deformable substrate is then attached to a curved, rigid substrate using epoxy or other suitable adhesives. The imprinted surface is facing away from the curved rigid substrate.

Improvements in Production of Single-Walled Carbon Nanotubes

TBMG-561109/01/2009

A continuing program of research and development has been directed toward improvement of a prior batch process in which single-walled carbon nanotubes are formed by catalytic disproportionation of carbon monoxide in a fluidized-bed reactor. The overall effect of the improvements has been to make progress toward converting the process from a batch mode to a continuous mode and to scaling of production to larger quantities. Efforts have also been made to optimize associated purification and dispersion post processes to make them effective at large scales and to investigate means of incorporating the purified products into composite materials. The ultimate purpose of the program is to enable the production of high-quality single-walled carbon nanotubes in quantities large enough and at costs low enough to foster the further development of practical applications.

Silica-Aerogel Composites Opacified With La_0.7Sr_0.3MnO₃

TBMG-553308/01/2009

As part of an effort to develop improved lightweight thermal-insulation tiles to withstand temperatures up to 1,000 °C, silica aerogel/fused-quartz- fiber composite materials containing La0.7Sr0.3MnO3 particles as opacifiers have been investigated as potentially offering thermal conductivities lower than those of the otherwise equivalent silica-aerogel composite materials not containing La0.7Sr0.3MnO3 particles. The basic idea of incorporating opacifying particles into silica-aerogels composite to reduce infrared radiative contributions to thermal conductivities at high temperatures is not new: it has been reported in a number of previous NASA Tech Briefs articles. What is new here is the selection of La0.7Sr0.3MnO3 particles as candidate opacifiers that, in comparison with some prior opacifiers (carbon black and metal nanoparticles), are more thermally stable.

Inert Welding/Brazing Gas Filters and Dryers

TBMG-551408/01/2009

A system has been designed to reduce the hydrogen molecule content in inert gases that are used for shielding the welding arc and molten weld area during the manual fusion, automated welding, and induction brazing process. Two desiccant pipeline dryer cartridges are connected together using either aircraft or KC .250 fittings, and are installed in-line between the inert-gas facility source (argon and helium) and the welding machine. This process helps maintain alloy grain structure and integrity to engineering specifications during the welding and brazing processes. Also, this method enhances weldability when joining similar and dissimilar alloys. It is easy to restore the system to original drying capabilities by using a nitrogen purge or by oven drying. This design has low schedule impact or down time when being installed on machines or in systems. There is also a sight glass to indicate when servicing is needed.

Water Reclamation Using Spray Drying

2009-01-236407/12/2009

Spray drying is a continuous physical separation process where a solution is sprayed into a hot drying medium. The resulting products are dry solute particles and the drying medium bearing the solvent vapor. Using one of several methods the solvent is recovered from the drying medium. The exact nature of the dried solid and recovered solvent depends on the physical and chemical properties of the feed and the design and operation of the dryer. In this paper we discuss progress made on the development of a prototype for advanced life support applications, and provide data on its purification abilities. A system processing 1 kg hr−1 of aqueous brine solution consumes on the order of 1000 W, but this value was strongly tied to other processing parameters such as dryer inlet and exit temperatures and the heating mode. Analysis of recovered water having an initial concentration of 48000 ppm TDS had between 12 and 134 ppm TDS and strongly depended on the processing conditions. Analysis of

Coppa, N. V., Chandler, K. V.

Light-Curing Adhesive Repair Tapes

TBMG-541407/01/2009

Adhesive tapes, the adhesive resins of which can be cured (and thereby rigidized) by exposure to ultraviolet and/or visible light, are being developed as repair patch materials. The tapes, including their resin components, consist entirely of solid, low-out-gassing, nonhazardous or minimally hazardous materials. They can be used in air or in vacuum and can be cured rapidly, even at temperatures as low as –20 °C. Although these tapes were originally intended for use in repairing structures in outer space, they can also be used on Earth for quickly repairing a wide variety of structures. They can be expected to be especially useful in situations in which it is necessary to rigidize tapes after wrapping them around or pressing them onto the parts to be repaired.

Fabricating PFPE Membranes for Capillary Electrophoresis

TBMG-517505/01/2009

A process has been developed for fabricating perfluoropolyether (PFPE) membranes that contain microscopic holes of precise sizes at precise locations. The membranes are to be incorporated into “laboratory-on-a-chip” microfluidic devices to be used in performing capillary electrophoresis.

Composite Bipolar Plate for Unitized Fuel Cell/Electrolyzer Systems

TBMG-505504/01/2009

In a substantial improvement over present alkaline systems, an advanced hybrid bipolar plate for a unitized fuel cell/ electrolyzer has been developed. This design, which operates on pure feed streams (H2/O2 and water, respectively) consists of a porous metallic foil filled with a polymer that has very high water transport properties. Combined with a second metallic plate, the pore-filled metallic plates form a bipolar plate with an empty cavity in the center.

A Simplified Diagnostic Method for Elastomer Bond Durability

TBMG-353802/01/2009

A simplified method has been developed for determining bond durability under exposure to water or high humidity conditions. It uses a small number of test specimens with relatively short times of water exposure at elevated temperature. The method is also gravimetric; the only equipment being required is an oven, specimen jars, and a conventional laboratory balance.

Mechanized Harvesting of Plants in a Controlled Environment

TBMG-TB-00324309/23/2008

The proposed Plant Harvesting Mechanization System (PHARMS) would comprise machinery and controls for semiautomated harvesting of plants grown in a controlled environment. The PHARMS was conceived as a prototype of harvesters to be incorporated into life-support systems of spacecraft and remote planetary bases, wherein plants would provide food and contribute to recycling of air and water. On Earth, PHARMS-like systems could reduce the labor of harvesting plants from protected agricultural systems in which special fruits and vegetables, herbs, ornamental plants, and mushrooms are grown. At harvest time, the PHARMS would be moved from storage to a location near the plantgrowth chamber. There, it would be unfolded from a compact configuration, then prepared for operation by setting of control parameters and mechanical alignment with the chamber and plants. In operation, the PHARMS would pull plant trays out of the chamber and remove plants from the trays. Then it would subject the plants

Improved Silica Aerogel Composite Materials

TBMG-312509/01/2008

A family of aerogel-matrix composite materials having thermal-stability and mechanical-integrity properties better than those of neat aerogels has been developed. Aerogels are known to be excellent thermal- and acoustic-insulation materials because of their molecular-scale porosity, but heretofore, the use of aerogels has been inhibited by two factors:

Capillography of Mats of Nanofibers

TBMG-308109/01/2008

Capillography (from the Latin capillus, “hair”, and the Greek graphein, “to write”) is a recently conceived technique for forming mats of nanofibers into useful patterns. The concept was inspired by experiments on carpetlike mats of multiwalled carbon nanotubes. Capillography may have the potential to be a less-expensive, less- time-consuming alternative to electron- beam lithography as a means of nanoscale patterning for the fabrication of small devices and instruments.

Probing a Spray Using Frequency-Analyzed Light Scattering

TBMG-272404/01/2008

Frequency-analyzed laser-light scattering (FALLS) is a relatively simple technique that can be used to measure principal characteristics of a sheet of sprayed liquid as it breaks up into ligaments and then the ligaments break up into droplets. In particular, through frequency analysis of laser light scattered from a spray, it is possible to determine whether the laser- illuminated portion of the spray is in the intact-sheet region, the ligament region, or the droplet region. By logical extension, it is possible to determine the intact length from the location of the laser beam at the transition between the intact-sheet and ligament regions and to determine a breakup frequency from the results of the frequency analysis. Hence, FALLS could likely be useful both as a means of performing research on sprays in general and as a means of diagnostic sensing in diverse applications in which liquid fuels are sprayed. Sprays are also used for drying and to deposit paints and other coating

Automating cavity-wax application

AUTOFEB08_0602/01/2008

European standard enters the U.S. marketplace as automation of the complex operation takes over. The automotive market is becoming less confined by hemispheric boundaries. International manufacturers are opening plants on North American soil and bringing with them European technology and standards not typically used by U.S. auto manufacturers. One of these is vehicle cavity wax. Robert Nadler, the Team Leader in design-engineering and tooling for wax application at the BMW Group, Surface Technology Coating and Application Centre, explained that cavity wax is the European standard for vehicle corrosion protection.

Polyaniline Compounds for Protection Against Corrosion

TBMG-TB-00214708/21/2007

Protective surface layers can be formulated and applied in various ways. Corrosion of iron and steel substrates can be inhibited by coating them with any of the wide variety of compounds denoted generally as polyanilines. A polyaniline suitable for this type of application can be in either an electrically conductive salt (doped) form or an electrically nonconductive base form. Typically, polyaniline is dissolved in an organic solvent and the resulting solution is applied to a substrate by spraying, dipping, or brushing. The solvent is then allowed to evaporate leaving the substrate coated with a solid film of polyaniline, typically 1 to 200µm thick.

Fabrication of Lightweight Armored Doors for HMMWVs

TBMG-461908/01/2007

A document describes a concept for fabricating lightweight armored doors for the Army’s high-mobility multipurpose wheeled vehicles (HMMWVs). Essentially, the concept is to reinforce high-hard (HH) steel armored doors used on some HMMWVs with a laminated, woven, high-tensile-strength glassfiber/ polyester-matrix composite that has performed well as armor material in previous military applications. A fabrication procedure for implementing the concept, described in the document, can be summarized as follows:

Magnetic Rubber Inspection Material

AMS2309A (Current)04/05/2007

This specification covers an inspection material in the form of a liquid room-temperature vulcanizing rubber filled with magnetic particles which is cured by addition of one or more curing agents. The product may be supplied in a variety of viscosities and colors.

AMS K Non Destructive Methods and Processes Committee

Double-Vacuum-Bag Process for Making Resin-Matrix Composites

TBMG-111801/01/2007

A double-vacuum-bag process has been devised as a superior alternative to a single-vacuum-bag process used heretofore in making laminated fiber-reinforced resin-matrix composite-material structural components. This process is applicable to broad classes of high-performance matrix resins — including polyimides and phenolics — that emit volatile compounds (solvents and volatile by-products of resin-curing chemical reactions) during processing. The superiority of the double-vacuum-bag process lies in enhanced management of the volatile compounds. Proper management of volatiles is necessary for making composite material components of high quality: if not removed and otherwise properly managed, volatiles can accumulate in interior pockets as resins cure, thereby forming undesired voids in the finished products.

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