Keyword: Composite materials

Briefs: Materials
Novel Low-Density Ablators Containing Hyperbranched Poly(azomethine)s

An ablative composite is low-density (0.25 to 0.40 g/cm3), easy to fabricate, and superior to the current state-of-the-art ablator (phenolic impregnated carbon ablator, PICA) in terms of decomposition temperature, char yield, and mechanical strength. Initial...

Articles: Energy

You might think a wind turbine would have more in common with a plane’s propeller than an aircraft wing, but wind blades...

Briefs: Materials
Fire-Retardant Polymeric Additives

Polyhydroxyamide (PHA) and polymethoxyamide (PMeOA) are fire-retardant (FR) thermoplastic polymers and have been found to be useful as an additive for imparting fire retardant properties to other compatible, thermoplastic polymers (including some elastomers). Examples of compatible flammable polymers include...

Briefs: Manufacturing & Prototyping
Antimicrobial-Coated Granules for Disinfecting Water

Methods of preparing antimicrobial-coated granules for disinfecting flowing potable water have been developed. Like the methods reported in the immediately preceding article, these methods involve chemical preparation of substrate surfaces (in this case, the surfaces of granules) to enable...

Briefs: Materials
Lightweight, Ultra-High-Temperature, CMC-Lined Carbon/Carbon Structures

lished engineering material used extensively in aerospace. The beneficial properties of C/C include high strength, low density, and toughness. Its shortcoming is its limited usability at temperatures higher than the oxidation temperature of carbon — approximately 400 °C....

Briefs: Manufacturing & Prototyping
Hybrid Composite Cryogenic Tank Structure

A hybrid lightweight composite tank has been created using specially designed materials and manufacturing processes. The tank is produced by using a hybrid structure consisting of at least two reinforced composite material systems. The inner composite layer comprises a distinct fiber and resin matrix...

Briefs: Manufacturing & Prototyping
Reliability-Based Design Optimization of a Composite Airframe Component

A stochastic optimization methodology (SDO) has been developed to design air-frame structural components made of metallic and composite materials. The design method accommodates uncertainties in load, strength, and material properties that are defined by distribution...

Briefs: Manufacturing & Prototyping
Zinc Oxide Nanowire Interphase for Enhanced Lightweight Polymer Fiber Composites

The objective of this work was to increase the interfacial strength between aramid fiber and epoxy matrix. This was achieved by functionalizing the aramid fiber followed by growth of a layer of ZnO nanowires on the fiber surface such that when embedded into the...

Briefs: Materials
Nanoparticle/Polymer Nanocomposite Bond Coat or Coating

This innovation addresses the problem of coatings (meant to reduce gas permeation) applied to polymer matrix composites spalling off in service due to incompatibility with the polymer matrix. A bond coat/coating has been created that uses chemically functionalized nanoparticles (either clay...

Briefs: Physical Sciences
Active Flow Effectors for Noise and Separation Control

New flow effector technology for separation control and enhanced mixing is based upon shape memory alloy hybrid composite (SMAHC) technology. The technology allows for variable shape control of aircraft structures through actively deformable surfaces. The flow effectors are made by embedding...

Briefs: Manufacturing & Prototyping
Economical Fabrication of Thick-Section Ceramic Matrix Composites

A method was developed for producing thick-section [>2 in. (≈5 cm)], continuous fiber-reinforced ceramic matrix composites (CMCs). Ultramet-modified fiber interface coating and melt infiltration processing, developed previously for thin-section components, were used for the...

Briefs: Manufacturing & Prototyping
Process To Produce Iron Nanoparticle Lunar Dust Simulant Composite

A document discusses a method for producing nanophase iron lunar dust composite simulant by heating a mixture of carbon black and current lunar simulant types (mixed oxide including iron oxide) at a high temperature to reduce ionic iron into elemental iron. The product is a...

Articles: Green Design & Manufacturing

You might think a wind turbine would have more in common with a plane’s propeller than an aircraft wing, but wind blades actually...

Briefs: Materials
Determining Shear Stress Distribution in a Laminate

A “simplified shear solution” method approximates the through-thickness shear stress distribution within a composite laminate based on an extension of laminated beam theory. The method does not consider the solution of a particular boundary value problem; rather, it requires only knowledge...

Briefs: Physical Sciences

Recently, there has been a considerable effort to study the Casimir and van der Waals forces, enabled by the improved ability to measure small...

Briefs: Physical Sciences
Autonomous System for Monitoring the Integrity of Composite Fan Housings

A low-cost and reliable system assesses the integrity of composite fan-containment structures. The system utilizes a network of miniature sensors integrated with the structure to scan the entire structural area for any impact events and resulting structural damage, and to...

Briefs: Physical Sciences
Instrument for Measuring Thermal Conductivity of Materials at Low Temperatures

With the advance of polymer and other non-metallic material sciences, whole new series of polymeric materials and composites are being created. These materials are being optimized for many different applications including cryogenic and low-temperature industrial...

Briefs: Materials
High-Temperature Solid Lubricant Coating

NASA PS400 is a solid lubricant coating invented for high-temperature tribological applications. This plasma-sprayed coating is a variant of the previously patented PS304 coating, and has been formulated to provide higher density, smoother surface finish, and better dimensional stability.

Briefs: Materials

Sublimation is a major cause of degradation of thermoelectric power generation systems. Most thermoelectric materials tend to have peak values at the temperature...

Briefs: Materials
Silica/Polymer and Silica/Polymer/Fiber Composite Aerogels

Aerogels that consist, variously, of neat silica/polymer alloys and silica/polymer alloy matrices reinforced with fibers have been developed as materials for flexible thermal-insulation blankets. In comparison with prior aerogel blankets, these aerogel blankets are more durable and less...

Briefs: Energy
In recent years, better stabilizer formulations for ethylene vinyl-acetate have been developed, giving more confidence in the long-term stability of PV packaging materials. Because of this, some manufacturers have stopped using Ce-doped glass. National Renewable Energy Laboratory researchers studied Ce-free glass.
Briefs: Materials
Exfoliated Graphite Nano-Reinforcements With Surface Modifications to Improve Dispersability

Exfoliated graphite nanoflakes are a potential low-cost source of nano-reinforcement for making polymer composites with unique properties. The chemical nature of the graphitic surface leads to a low-surface energy as produced. This makes the nanoflakes...

Briefs: Mechanical & Fluid Systems
Hybrid Heat Exchangers

A hybrid light-weight heat exchanger concept has been developed that uses high-conductivity carbon-carbon (C–C) composites as the heat-transfer fins and uses conventional high-temperature metals, such as Inconel, nickel, and titanium as the parting sheets to meet leakage and structural requirements.

Briefs: Materials
Modeling of Failure for Analysis of Triaxial Braided Carbon Fiber Composites

In the development of advanced aircraft-engine fan cases and containment systems, composite materials are beginning to be used due to their low weight and high strength. The design of these structures must include the capability of withstanding impact loads from a...

Briefs: Software
Probabilistic Structural Analysis Program

NASA/NESSUS 6.2c is a general-purpose, probabilistic analysis program that computes probability of failure and probabilistic sensitivity measures of engineered systems. Because NASA/NESSUS uses highly computationally efficient and accurate analysis techniques, probabilistic solutions can be obtained even...

Application Briefs: Photonics/Optics

Fiber reinforced polymer composites are revolutionizing the design of large, high-performance structures in the aerospace, marine and power generation industries due to their...

Application Briefs: Sensors/Data Acquisition

Fiber reinforced polymer composites are revolutionizing the design of large, high-performance structures in the aerospace, marine and power generation industries due to their...

Briefs: Materials
Wider-Opening Dewar Flasks for Cryogenic Storage

Dewar flasks have been proposed as containers for relatively long-term (25 days) storage of perishable scientific samples or other perishable objects at a temperature of –175 °C. The refrigeration would be maintained through slow boiling of liquid nitrogen (LN2). For the purposes of...

Briefs: Materials
Silicon Oxycarbide Aerogels for High-Temperature Thermal Insulation

A high-performance, silicon oxycarbide (SiOC) aerogel material is suitable for use as thermal insulation at temperatures approaching 1,200 °C. These aerogel composites were created using cost-effective and commercially available polymeric precursors (the polymethylsiloxane...