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Journal Article

Effects of Reflux Temperature and Molarity of Acidic Solution on Chemical Functionalization of Helical Carbon Nanotubes

2017-09-19
Abstract The use of nanomaterials and nanostructures have been revolutionizing the advancements of science and technology in various engineering and medical fields. As an example, Carbon Nanotubes (CNTs) have been extensively used for the improvement of mechanical, thermal, electrical, magnetic, and deteriorative properties of traditional composite materials for applications in high-performance structures. The exceptional materials properties of CNTs (i.e., mechanical, magnetic, thermal, and electrical) have introduced them as promising candidates for reinforcement of traditional composites. Most structural configurations of CNTs provide superior material properties; however, their geometrical shapes can deliver different features and characteristics. As one of the unique geometrical configurations, helical CNTs have a great potential for improvement of mechanical, thermal, and electrical properties of polymeric resin composites.
Standard

NATIONAL AEROSPACE AND DEFENSE CONTRACTORS ACCREDITATION PROGRAM REQUIREMENTS FOR NONCONVENTIONAL MACHINING

2002-02-01
HISTORICAL
AS7116
This Aerospace Standard (AS) establishes the requirements for suppliers of Nonconventional Machining Services to be accredited by the National Aerospace and Defense Contractors Accreditation Program (NADCAP). NADCAP accreditation is granted in accordance with SAE AS7003 after demonstration of compliance with the requirements herein. The requirements may be supplemented by additional requirements specified by the NADCAP Nonconventional Machining and Surface Enhancement (NMSE) Task Group. Using the corresponding Audit Criteria (PRI AC7116) will ensure that accredited Nonconventional Machining suppliers meet all of the requirements in this standard and all applicable supplementary standards. The purpose of this audit program is to assess a supplier's ability to consistently provide a product or service that conforms to the technical specifications and customer requirements.
Technical Paper

Guiding Framework for Feasibility Evaluation of Localised Production and Drop in Blending of Aviation Turbine Fuel with Bio Derivatives for Non-civilian Air Bases

2011-10-18
2011-01-2792
The potential for small scale local production of Bio fuel derivatives and their partial blending with aviation turbine fuel in non-civilian bases has been investigated. A feasibility study on technical readiness levels for process viability is presented in the paper. Demand side analysis for various blend mixes and corresponding requirement for production facilities and land area requirements are performed. Sustainable production and blending operations are the basis for selection of key performance indicators for the air base. Guiding framework and readiness evaluation processes are delineated for the base. Qualitative inference is combined with quantitative scoring system within the framework.
Technical Paper

Computing Remaining Fatigue Life Under Incrementally Updated Loading Histories

2018-04-03
2018-01-0623
After manufacture, every military vehicle experiences a unique history of dynamic loads, depending on loads carried, missions completed, etc. Damage accumulates in vehicle structures and components accordingly, leading eventually to failures that can be difficult to anticipate, and to unpredictable consequences for mission objectives. The advent of simulation-based fatigue life prediction tools opens a path to Digital Twin based solutions for tracking damage, and for gaining control over vehicle reliability. An incremental damage updating feature has now been implemented in the Endurica CL fatigue solver with the aim of supporting such applications for elastomer components. The incremental updating feature is demonstrated via the example of a simple transmission mount component. The damage state of the mount is computed as it progresses towards failure under a series of typical loading histories.
Research Report

Unsettled Topics on Nondestructive Testing of Additively Manufactured Parts in the Mobility Industry

2020-09-29
EPR2020017
Additive manufacturing (AM) technology, also known as 3D printing, has transitioned from concepts and prototypes to part-for-part substitution and the creation of unique AM-specific part geometries. These applications are increasingly present in demanding, mission-critical fields such as medicine and aerospace, which require materials with certain thermal, stiffness, corrosion, and static loading properties. To advance in these arenas, metallic, ceramic, and polymer composite AM parts need to be free from discontinuities. The manufacturing processes have to be stable, robust, and repeatable. And the nondestructive testing (NDT) technology and inspection methods will need to be sufficiently capable and reliable to ensure that discontinuities will be detected to prevent the components from being accepted for use. As the second installment of a six-part series of SAE EDGE™ Research Reports on AM, this one discusses the need, challenges, technologies, and opportunities for NDT in AM.
Research Report

Internal Boundaries of Metal Additive Manufacturing: Future Process Selection

2022-03-11
EPR2022006
In the early days, there were significant limitations to the build size of laser powder bed fusion (L-PBF) additive manufacturing (AM) machines. However, machine builders have addressed that drawback by introducing larger L-PBF machines with expansive build volumes. As these machines grow, their size capability approaches that of directed energy deposition (DED) machines. Concurrently, DED machines have gained additional axes of motion which enable increasingly complex part geometries—resulting in near-overlap in capabilities at the large end of the L-PBF build size. Additionally, competing technologies, such as binder jet AM and metal material extrusion, have also increased in capability, albeit with different starting points. As a result, the lines of demarcation between different processes are becoming blurred.
Technical Paper

Numerical Analysis of Lightweight Materials and their Combinations to Understand their Behaviour against High Pressure Shock Loading

2023-05-25
2023-28-1311
Materials play a key role in our day to day life and have shaped the industrial revolution to a great extent. Right selection of material for meeting a particular objective is the key to success in today’s world where the cost as well as sustainability of any equipment or a system have assumed greater significance than ever before. In automotive industry, materials have a definitive role as far as the mobility and safety is concerned. Materials that can absorb the required energy or impact can be manufactured through different manufacturing as well as metallurgical processes which involves appropriate heat treatment and bringing correct chemical compositions etc. However, they can also be formed by simpler methods such as combining certain materials together in the form of layered combinations to form light weight composites.
Technical Paper

Design and Development of Fuel Tank for High Mobility Military Vehicle

2023-05-25
2023-28-1342
Fuel tank is considered as safety component in the vehicle, and it has to be tested to meet the safety requirements as per AIS 095. Earlier, fuel tanks were manufactured by using Hot dipped cold rolled steel material and the weld zones are applied with Anti-corrosive coating. Few fuel tanks were reported with Corrosion problems. The root cause analysis was carried out considering the raw material, manufacturing process, transpiration, storage and usage. As an improvement, the new fuel tank is designed to eliminate the limitations of the existing fuel tank. 3D modeling was done to check space and mounting requirement in the layout and used for volume calculations. FE analysis was performed to check structural stability. Emphasis given on Interchange-ability to cater the new fuel tanks in place of old as spares requirement. The fuel tank has developed with Alumina steel material.
Technical Paper

MVMDNet: A Weakly-Supervised Multi-View Enhancing Network for Mass Detection in Mammograms

2022-06-28
2022-01-7030
Mass is one important suspicious object for breast cancer diagnosis in mammograms. Computer-aided detection (CAD) based on fully supervised deep learning achieves high performance for mass detection in mammograms. The lack of fine-grained expert labels becomes the bottleneck for the large-scale application of CAD to achieve detection in mammograms. Weakly supervised methods provide a solution to tackle the annotation problems, including in the application for mass detection. However, previous works face the problem of insufficient localization information, which affect the ability of mass detection. In this paper, we propose a multi-view enhancing mass detection network (MVMDNet) with dual view inputs that contains craniocaudal (CC) and mediolateral oblique (MLO) view of mammograms, where different view features are interacted and fused to enhance localization information.
Magazine

Aerospace & Defense Technology: August 2021

2021-08-01
Thermal Management Techniques in Avionics Cooling Curing the Porosity Problem in Additive Manufacturing Space-Qualified Crystal Oscillators Reimagining Automated Test During a Pandemic EW: New Challenges, Technologies, and Requirements Software Enables New-Age, Flexible Test Solution for Analog and Digital Radios Formal Process Modeling to Improve Human-Decision-Making During Test and Evaluation Range Control Using the Innoslate software tool to formally model the process of conducting test range events can expose previously overlooked ambiguities and identify high-value decision points? Test and Evaluation of Autonomy for Air Platforms Tools, approaches, and insights to confidently approach the safe, secure, effective, and efficient testing of autonomy on air platforms.
Training / Education

Metals Bundle

Anytime
Almost 75% of all elements are metals. Metals can be classified as either ferrous or non-ferrous and generally conduct electricity and heat well. Most metals are malleable and ductile and are, in general, heavier than other elemental substances. The following six eLearning courses are included in the Materials bundle. Each course is approximately one-hour in duration. See topics/outline for additional details. Introduction to Metals, Ferrous Metals, Nonferrous Metals, Classification of Steel, Essentials of Heat Treatment of Steel Exotic Alloys
Journal Article

Infrared Signature of Fixed and Variable Area C-D Nozzle of Aircraft Engine

2023-01-02
Abstract The use of converging-diverging (C-D) variable area nozzle (VAN) in military aeroengines is now common, as it can give optimal expansion and control over engine back pressure, for a wide range of engine operations. At higher main combustion temperatures (desired for supercruise), an increase in the nozzle expansion ratio is needed for optimum performance. But changes in the nozzle throat and exit areas affect the visibility of engine hot parts as the diverging section of the nozzle is visible for a full range of view angle from the rear aspect. The solid angle subtended by engine hot parts varies with change in visibility, which affects the aircraft infrared (IR) signature from the rear aspect. This study compares the performances of fixed and variable area nozzles (FAN and VAN) in terms of engine thrust and IR signature of the engine exhaust system in the boresight for the same increase in combustion temperature.
Research Report

Process Control for Defect Mitigation in Laser Powder Bed Fusion Additive Manufacturing

2023-05-15
EPR2023011
Success in metal additive manufacturing (AM) relies on the optimization of a large set of process parameters to achieve materials whose properties and performance meet design and safety requirements. Despite continuous improvements in the process over the years, the quality of AM parts remains a major concern for manufacturers. Today, researchers are starting to move from discrete geometry-dependent build parameters to continuously variable or dynamically changing parameters that are geometry- and scan-path aware. This approach has become known as “feedforward control.” Process Control for Defect Mitigation in Laser Powder Bed Fusion Additive Manufacturing discusses the origins of feedforward control, its early implementations in AM, the current state of the art, and a path forward to its broader adoption. Click here to access the full SAE EDGETM Research Report portfolio.
Standard

Diminishing Manufacturing Sources and Material Shortages (DMSMS) Management Practices

2015-07-01
CURRENT
GEB1
This document includes a standard set of management practices that can be used, or espoused, by the OEMs for use during the design and development of electronic systems to mitigate the effects of future Diminishing Manufacturing Sources and Material Shortages (DMSMS). While this document focuses primarily on microelectronic devices, the methods described here may also apply to other commodities.
Training / Education

Ferrous Metals Bundle: Steel and Cast Iron

Anytime
Ferrous metals contain iron and are prized for their tensile strength and durability. Most are magnetic and contain a high carbon content which generally makes them, with the exception of wrought iron and stainless steel, vulnerable to rust. The following seven eLearning courses are included in the Ferrous Materials Bundle: Steel and Cast Iron. Each course is approximately one-hour in duration. Modules include: Introduction to Physical Properties, Introduction to Mechanical Properties, Introduction to Metals, Hardness Testing, Ferrous Metals, Classification of Steel, Essentials of Heat Treatment of Steel.
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