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Viewing 241 to 270 of 15895
2016-09-27
Technical Paper
2016-01-2113
Raphael Reinhold
Abstract Resin transfer molding (RTM) is gaining importance as a particularly economical manufacturing method for composites needed in the automotive and aerospace industries. With this method, the component is first shaped with dry fiber reinforcements in a so-called “preforming process” before the mold is placed in a RTM tool, injected with resin and cured. In recent years, Broetje-Automation has been developing innovative product solutions that are specially designed for these preforming processes and suitable for industrial use. For the first time ever, Broetje’s Composite Preforming Cell (CPC) makes large-quantity serial production of complex and near-net-shape preforms for composite components using this RTM process possible. With the additional integration of the patented 3D Composite Handling System Broetje impressively demonstrates its service and product portfolio in the area of innovative composite manufacturing technology and its know-how as a complete system integrator.
2016-09-27
Technical Paper
2016-01-2114
Matthias Meyer
Carbon composites have been on an odyssey within the past 15 years. Starting on the highest expectations regarding the performance, reality was hitting a lot of programs hard. Carbon composites were introduced on a very high technical level and industry has shown of being capable to handle those processes in general. In particular, production never sleeps and processes undergo a continuous change. Within these changes costs remain the most critical driver. As products are improving during their lifetime, they usually increase the degree of complexity, too. According to the normal cost improvement, this has drastic consequences for production. When setting up the first generation of composite production, the part being produced has been in the centre of attention.
2016-09-27
Technical Paper
2016-01-2117
Rustam M. Baytimerov, Pavel Lykov, Sergei Sapozhnikov, Dmitry Zherebtsov, Konstantin Bromer
Abstract The development of Additive Technologies (SLS/SLM, EBM, DMD) suggests the increase of range expansion of materials used. One of the most promising directions is products manufacturing from composite materials. The technology of composite micro-powders production on the basis of heat-resistant nickel alloy EP648 and Al2O3 is proposed. The aim of this research is to develop a method of producing composite micropowders for additive technology application. This method is based on modification of the metal micropowders surface by the second phase in a planetary mixer (mechanochemical synthesis).The obtained composite micropowders are compared with powders which are recommended for selective laser melting usage (produced by MTT Technology). The equipment used in the research: planetary mixer, scanning electron microscopy (SEM), optical granulomorphometer Occio 500nano.
2016-09-27
Technical Paper
2016-01-2123
Matthias Busch, Benedikt Faupel
Abstract The integration of omega stringers to panels made of carbon fiber reinforced plastic (CFRP) by adhesive bonding, which is achieved by baking in an autoclave, must be subject to high quality standards. Failures such as porosity, voids or inclusion must be detected safely to guaranty the functionality of the component. Therefore, an inspection system is required to verify these bonds and detect different kinds of defects. In this contribution, the advantages of a robotic inspection system, which will be achieved through continuous testing, will be introduced. The testing method is the active thermography. The active thermography has major advantages compared with other non-destructive testing methods. Compared to testing with ultrasonic there is no coupling medium necessary, thus testing will be significantly enhanced.
2016-09-27
Technical Paper
2016-01-2121
Pavel Lykov, Rustam M. Baytimerov, Artem Leyvi, Dmitry Zherebtsov, Alexey Shultc
Abstract The copper-nickel alloys are widely used in various industries. The adding of nickel significantly enhances mechanical properties, corrosion resistance and thermoelectric properties of copper. The technology was proposed of production of copper-nickel composite micro-powders by the gaseous deposition of nickel on the surface of copper powder. The vaporization of nickel was implemented by using magnetron. The relationship between mode of processing and the ratio of phases in the powder was investigated. The proposed method allows to modify the powder surface without deformation of the particles. The possibility of using of obtained composite powder in selective laser melting (SLM) was evaluated. It is assumed that the structure of the obtained composite material (SLM) will have inclusions of nickel and continuous chain of copper. This structure will have high mechanical properties and high electrical conductivity.
2016-09-27
Technical Paper
2016-01-2125
Henry Hameister
This paper presents an approach to how existing production systems can benefit from Industry 4.0 driven concepts. This attempt is based on a communication gateway and a cloud-based system, that hosts all algorithms and models to calculate a prediction of the tool wear. As an example we will show the Refill Friction Stir Spot Welding (RFSSW), a solid state joining technique, which is examined at the Institute of Production Engineering (LaFT) of the Helmut-Schmidt-University, University of the Federal Armed Forces Hamburg, for years. RFSSW is a sub-section of friction welding, where a rotating tool that consists out of three parts is used to heat up material to a dough-like state. Since Refill Friction Stir Spot Welding produces a selective dot-shaped connection of overlapping materials, the production requirements are similar to riveting or resistance spot welding.
2016-09-27
Technical Paper
2016-01-2129
Antonio Rubio, Luis Calleja, Javier Orive, Ángel Mújica, Asunción Rivero
Abstract Aluminum skin milling is a very challenging process due to the high quality requirements needed in the aeronautic and aerospace industries. Nowadays, on these markets, there are just two technological approaches able to face the manufacturing of this sort of wide thin blanks: chemical and mechanical milling by means of highly complex machines. Both solutions lead to a high investment requirement that affect directly on the application profitability on these industrial sectors. This paper presents a flexible machining system that allows milling skin shaped parts within required tolerances by means of an innovative universal holding fixture combined with an adaptive toolpath development. This flexible holding fixture can be adapted to the required shape and can hold uniformly the whole sheet surface. Besides, the solution includes an implementation that can adapt the machining toolpath by means of the skin thickness online measurement.
2016-09-27
Technical Paper
2016-01-2142
Pavel Lykov PhD, Artem Leyvi, Rustam M. Baytimerov, Aleksei Doikin, Evgeny Safonov
Abstract The treatment of solid surface by powerful streams of charged particles accelerated with power density ≥106 W/cm2 widely used for modification of different materials properties. The fast enter of electron beam power in the material of target causes the flow intense thermal and deformation processes. The changing of the structure, the phase composition, the microrelief of treated surface consequently happens. It is often accompanied by the hardening and increase of the wearing properties. The work proposed of using low-energy high-current electron beam as finish treatment of product obtained by selective laser melting of heat-resistant nickel alloy EP648. The subject of research was the surface properties of the product.
2016-09-27
Technical Paper
2016-01-2124
Sara Nilsson, Jonas Jensen, Mats Björkman, Erik Sundin
Abstract Carbon fiber-reinforced plastic (CFRP) is one of the most commonly used materials in the aerospace industry today. CFRP in pre-impregnated form is an anisotropic material whose properties can be controlled to a high level by the designer. Sometimes, these properties make the material hard to predict with regards to how the geometry affects manufacturing aspects. This paper describes eleven design rules originating from different guidelines that describe geometrical design choices and deals with manufacturability problems that are connected to them, why they are connected and how they can be minimized or avoided. Examples of design choices dealt with in the rules include double curvature shapes, assembly of uncured CFRP components and access for non-destructive testing (NDT). To verify the technical content and ensure practicability, the rules were developed by, inter alia, studying literature and performing case studies at SAAB Aerostructures.
2016-09-27
Journal Article
2016-01-8066
Marco Maurizi, Daniel Hrdina
Abstract Total cost of ownership is requiring further improvements to piston friction reduction as well as additional gains in thermal efficiency. A piston compression height reduction in combination with carbon based piston pin coatings is enabling advancements in both demands. MAHLE implemented a new innovative metal joining technology by using laser welding to generate a cooling gallery. The MonoLite concept offers design flexibility which cannot be matched by any other welding process. Especially an optimum design and position of the cooling gallery as well as durability for very high peak cylinder pressures can be matched. This is particularly advantageous for complex combustion bowl geometries that are needed in modern diesel engines to meet fuel economy and emission requirements. The MonoLite steel piston technology offers a superior compression height reduction potential compared to typical friction welded designs.
2016-09-27
Technical Paper
2016-01-2101
Burak Deger, Fazli Melemez, Aykut Kibar lng
Abstract A hybrid drilling process of multi material stacks with one shot drilling recently emerge as an economical and time efficient method in aerospace industry. Even though the comprehensive experience and knowledge is available for the cutting parameters of composites and metals alone, significant gap exist for the hybrid drilling parameters. Determination of these parameters such as feed rate, spindle speed and pecking depth has vital importance so as to provide a robust and optimal process to ensure dimensionally high quality, burr and delamination free holes. Main challenge of hybrid drilling operation is to obtain required hole diameter with adequate homogeneity and repeatability. In this study, effect of cutting parameters on dimensional hole quality was investigated. In addition to the hole diameter tolerances, CFRP hole enlargement phenomena which is encountered as a specific drawback of metal-exit stack configurations is also addressed within the scope of this study.
2016-09-27
Journal Article
2016-01-2119
Gergis W. William, Samir N. Shoukry, Jacky C. Prucz, Mariana M. William
Abstract Air cargo containers are used to load freight on various types of aircrafts to expedite their handling. Fuel cost is the largest contributor to the total cost of ownership of an air cargo container. Therefore, a better fuel economy could be achieved by reducing the weight of such containers. This paper aims at developing innovative, lightweight design concepts for air cargo containers that would allow for weight reduction in the air cargo transportation industry. For this purpose, innovative design and assembly concepts of lightweight design configurations of air cargo containers have been developed through the applications of lightweight composites. A scaled model prototype of a typical air cargo container was built to assess the technical feasibility and economic viability of creating such a container from fiber-reinforced polymer (FRP) composite materials. The paper is the authoritative source for the abstract.
2016-09-27
Journal Article
2016-01-2116
Peter Mueller-Hummel
Abstract Drilling holes into metal with MQL (Minimal Quantity Lubrication) is a normal procedure, because the drill is designed for drilling metal and the malleable capability of the metal compensates for the insufficient cutting capability of a worn out drill. Drilling composite materials using the same drill (designed for drilling metal) is a different procedure, because composite fibers are not malleable like metal at all. Due to this fact the tools become very hot trying to forge composite fibers like metal. The elastic behavior of the composite and the delamination inside the hole makes the tool temporary smaller than the diameter of the drill. The hole in the metal part of the stack remains slightly larger due to the heat and the thermal expansion rate. This paper shows how to drill metal and composite with the same diameter, so that achieving H8 quality is no longer a dream.
2016-09-27
Journal Article
2016-01-2118
Patrick Land, Luis De Sousa, Svetan Ratchev, David Branson, Harvey Brookes, Jon Wright
Abstract With increased demand for composite materials in the aerospace sector there is a requirement for the development of manufacturing processes that enable larger and more complex geometries, whilst ensuring that the functionality and specific properties of the component are maintained. To achieve this, methods such as thermal roll forming are being considered. This method is relatively new to composite forming in the aerospace field, and as such there are currently issues with the formation of part defects during manufacture. Previous work has shown that precise control of the force applied to the composite surface during forming has the potential to prevent the formation of wrinkle defects. In this paper the development of various control strategies that can robustly adapt to different complex geometries are presented and compared within simulated and small scale experimental environments, on varying surface profiles.
2016-09-27
Journal Article
2016-01-2112
Hilmar Apmann
Abstract As a new material FML, made by aluminum foils and Glasfiber-Prepreg, is a real alternative to common materials for fuselages of aircrafts like monolithic aluminum or CFRP. Since experiences within A380 this material has some really good advantages and develops to the status as alternative to aluminum and composite structures. To become FML as a real alternative to aluminum and carbon structures there are many things to improve: design, material, costs and process chain. So following one of the main goals for an industrial application for high production rates of aircrafts is the automation of production processes inside the process chain for FML-parts like skins and panels for fuselages. To reach this goal for high production rates first steps of automation inside this new process chain have been developed in the last two years. Main steps is the automated lay-up of metallic foils and Glasfiber-Prepreg.
2016-09-27
Journal Article
2016-01-2126
Ali Mohamed Abdelhafeez, Sein Leung Soo, David Aspinwall, Anthony Dowson, Dick Arnold
Abstract Despite the increasing use of carbon fibre reinforced plastic (CFRP) composites, titanium and aluminium alloys still constitute a significant proportion of modern civil aircraft structures, which are primarily assembled via mechanical joining techniques. Drilling of fastening holes is therefore a critical operation, which has to meet stringent geometric tolerance and integrity criteria. The paper details the development of a three-dimensional (3D) finite element (FE) model for drilling aerospace grade aluminium (AA7010-T7451 and AA2024-T351) and titanium (Ti-6Al-4V) alloys. The FE simulation employed a Coupled Eulerian Lagrangian (CEL) technique. The cutting tool was modelled according to a Lagrangian formulation in which the mesh follows the material displacement while the workpiece was represented by a non-translating and material deformation independent Eulerian mesh.
2016-09-27
Technical Paper
2016-01-8027
Stefan Steidel, Thomas Halfmann, Manfred Baecker, Axel Gallrein
Abstract Rolling resistance and tread wear of tires do particularly influence the maintenance costs of commercial vehicles. Although tire labeling is established in Europe, it is meanwhile well-known that, due to the respective test procedures, these labels do not hold in realistic application scenarios in the field. This circumstance arises from the development phase of tires, where the respective performance properties are mainly evaluated in tire/wheel standalone scenarios in which the wide range of usage variability of commercial vehicles cannot be considered adequately. Within this article we address a method to predict indicators for rolling resistance and tread wear of tires in realistic application scenarios considering application-based factors of influence like specific customers, operation circumstances, regional dependencies, fleet specific characteristics etc.
2016-09-20
Technical Paper
2016-01-1996
David R. Markham, J. Michael Cutbirth
Abstract Modern military electronics systems are generating increasingly higher heat loads, necessitating larger capacity thermal management systems (TMSs). These high-capacity TMSs must meet the strict size and weight requirements of these advancing platforms. Commercially available compressor technology can generate sufficient cooling for these systems; however, they are too heavy and expansive. Mainstream Engineering Corporation has developed a compact, lightweight, high-speed screw compressor that can provide a large cooling capacity with a small package envelope. The compressor housing material is light-weight with a low coefficient of thermal expansion (CTE), allowing a wide operating temperature range. The compressor, with a nominal cooling capacity from 20 kW to 60 kW, was tested over a range of saturated suction conditions, pressure ratios, rotational speeds, and oil lubrication conditions.
2016-09-20
Journal Article
2016-01-2022
Ajay Rao, Vivek Karan, Pradeep Kumar
Abstract Turbulence is by far the number one concern of anxious passengers and a cause for airline injuries. Apart from causing discomfort to passengers, it also results in unplanned downtime of aircrafts. Currently the Air Traffic Control (ATC) and the meteorological weather charts aid the pilot in devising flight paths that avoid turbulent regions. Even with such tailored flight paths, pilots report constant encounters with turbulence. The probability of turbulence avoidance can be increased by the use of predictive models on historical and transactional data. This paper proposes the use of predictive analytics on meteorological data over the geographical area where the aircraft is intended to fly. The weather predictions are then relayed to the cloud server which can be accessed by the aircraft planned to fly in the same region. Predictive algorithms that use Time series forecasting models are discussed and their comparative performance is documented.
2016-09-20
Journal Article
2016-01-2071
Brian A. Hann
Abstract Laser Based Powder Bed Fusion, a specific application of additive manufacturing, has shown promise to replace traditionally fabricated components, including castings and wrought products (and multiple-piece assemblies thereof). In this process, powder is applied, layer by layer, to a build plate, and each layer is fused by a laser to the layers below. Depending on the component, it appears that only 3-5% of the powder charged into the powder bed fusion machine is fused. Honeywell’s initial part qualification efforts have prohibited the reuse of powder. Any unfused powder that exits the dispenser (i.e., surrounds the build or is captured in the overflow) is considered used. In order for the process to be broadly applicable in an economical manner, a methodology should be developed to render the balance of the powder (up to 97% of the initial charge weight) as re-usable.
2016-09-18
Technical Paper
2016-01-1910
Philippe Dufrenoy, Vincent Magnier, Ruddy MANN, Anne-Lise CRISTOL, ITZIAR SERRANO
Abstract An original methodology is described to characterize mechanical properties of braking sintered material from the microstructure. Firstly, a compressive test on cube extracted from the friction pad is performed. This compressive test is instrumented with a camera leading to use the digital image correlation method giving local information. Indeed, it is possible to identify the elastic and residual strains mechanisms and to make connection with the microstructure. All these information are introduced in a finite element analysis to identify the mechanical properties of the components using an optimization algorithm. As regards of the 2D measurements, it is relevant to confirm the tendency with a 3D information. Secondly, an ex-situ compression test in a micro tomography is performed. This test is coupled to digital image correlation and a 3D simulation is performed exhibiting elastic-plastic behavior and confirming results found in the 2D study.
2016-09-18
Technical Paper
2016-01-1932
Niclas Strömberg
Abstract During several years a toolbox for performing virtual rig tests of disc brake systems has been developed by the author. A thermo-flexible multi-body model of a test rig is derived and implemented by coupling two types of models: a finite element model and a multi-body model. The finite element model is a thermo-mechanical model of the pad-disc system that is formulated including thermo-elasticity, frictional contact and wear. The energy balance of the contact interface is governed by contact conductance that depends linearly on the contact pressure and the frictional heat depends on a temperature dependent coefficient of friction. Instead of adopting a standard Lagrangian approach, the disc is formulated in an Eulerian frame like a fluid. This is then coupled to the pad most accurately by using Signorini’s contact conditions, Coulomb’s law of friction and Archard’s law of wear.
2016-09-18
Technical Paper
2016-01-1942
Sarah Chen, Steve Hoxie
Abstract Developing a brake system with high overall customer satisfaction rating is a constant challenge for OEMs as well as their brake suppliers. Brake system performance is directly linked to the engagement between the rotors and pads. The materials for the rotors and pads play a key role in the nature of the engagement. Therefore, to meet the performance targets, it is critical to have a good understanding of the brake rotor materials and their impacts. Gray iron is the most widely used brake rotor material in the industry owing to its superior thermal handling capacity, damping characteristics, and wear and cost advantages. G30 per ASTM A48 is generally specified for most brake rotors with minimum tensile strength of 200 MPa and Brinell hardness of 187∼241. G20 is also widely used for brake rotors, especially for brake smoothness and optimal lining life.
2016-09-18
Technical Paper
2016-01-1957
Seonho Lee, Heejae Kang, Ohchul Kwon, Chirl Soo Shin
Abstract A trend in automotive parts development is the pursuit of long life, high quality and reliability. The increase in service life of automotive wheel bearings, by improving the rolling contact fatigue (RCF) life of bearing steels, was investigated. Conventional studies of bearing steels and heat treatments have dealt with quenching and tempering (Q/T) in 52100 steel. This study is a new trial to increase the strength of bearing steels by special austempering in phases after general Q/T heat treatments.
2016-09-18
Technical Paper
2016-01-1912
Bo Hu, Sydney Luk, Peter Filip
Abstract Copper and copper alloys are widely used in friction materials such as brake pad formulations as one of key ingredients by providing good thermal conductivity and high temperature friction stability to achieve desired friction performance, fade and wear resistance. However, the use of copper or copper containing material is being restricted in brake pads due to environment and health concerns. Extensive works have been made to explore the copper substitutes but most of these efforts became ineffective and failed with issues either thermal fade or excessive pad/rotor wear. In this paper, friction and wear responses were examined when a metallic composite material was used as the copper substitute in NAO and Low-met brake formulations where the copper and copper alloys were added 8% and 22% respectively.
2016-09-18
Technical Paper
2016-01-1916
Raffaele Gilardi, Davide Sarocchi, Loredana Bounous
Abstract A wide range of different carbon powders is available and currently used in friction materials like coke, graphite and carbon black. The effect of the type of carbon on braking performance has been extensively investigated in the past and it has been demonstrated that graphite can play an important role in copper-free brake pads. However, there are no studies about the influence of carbon powders on the processability of brake pads. Brake pads need to be painted in order to avoid corrosion. Typically electrostatic painting is used on an industrial scale, which requires the brake pads to be conductive. NAO brake pads (and especially Cu-free NAO brake pads) are rather insulating, and therefore difficult to paint. In this presentation we’ll show how special carbon powders can increase the electrical conductivity and therefore allow easy painting of brake pads. Based on these investigations, a new copper-free NAO formulation has been developed.
2016-09-18
Technical Paper
2016-01-1937
Taylor Erva, Adam Loukus, Luke Luskin
Abstract Aluminum metal matrix composite brake rotors with a selective ceramic function reinforcement gradient (FRG) have been developed for automotive applications. This paper will highlight the design, manufacturing, and testing of the rotors. Weight saving of an aluminum composite rotor in comparison to an industry standard cast iron rotor is 50-60%. With this material change comes design considerations to manage rotor temperature, rotor surface integrity, and friction. Manufacturing methods to meet these design constraints were needed to develop a viable high performance aluminum composite rotor. High pressure squeeze casting with soluble coring techniques were developed to incorporate the selective FRG MMC rotors. Dynamometer testing was performed, concentrating on brake friction and temperature to evaluate the macro and micro interfaces in the rotors.
2016-09-18
Technical Paper
2016-01-1926
Matthew Robere
Abstract Brake pad to rotor adhesion following exposure to corrosive environments, commonly referred to as “stiction”, continues to present braking engineers with challenges in predicting issues in early phases of development and in resolution once the condition has been identified. The goal of this study took on two parts - first to explore trends in field stiction data and how testing methods can be adapted to better replicate the vehicle issue at the component level, and second to explore the impacts of various brake pad physical properties variation on stiction propensity via a controlled design of experiments. Part one will involve comparison of various production hardware configurations on component level stiction tests with different levels of prior braking experience to evaluate conditioning effects on stiction breakaway force.
2016-09-18
Technical Paper
2016-01-1951
Björn Dingwerth
Abstract Caused by a number of beneficial properties inherently from the zinc-nickel material, this electrodeposited alloy is used more and more for cathodically protecting layers on ferrous components like cast iron brake calipers. Direct plating from acidic solutions is the state-of-the-art solution for zinc-nickel surface finishing of these components. To contribute to the continuous improvement of the final component and reduce the finishing cost, areas for improvement have been scrutinized in a current finishing system. Areas for improvement have been identified in the uniformity of the nickel distribution within different current densities and in the handling and economy of the metallic zinc anodes used for zinc metal replenishment. While today’s acidic zinc-nickel electrolytes suit and usually exceed the requirements for an alloy containing 10-15% nickel, nickel incorporation may drop just below 12% incorporation rate in areas which are plated at high current densities.
2016-09-18
Technical Paper
2016-01-1913
Alessandro Sanguineti, Federico Tosi, Andrea Bonfanti, Flavio Rampinelli
Abstract Organic brake pads for automotive can be defined as brake linings with bonding matrix constituted of high-temperature thermosetting resins. Bonded together inside the polymeric binder are a mix of components (e.g. abrasives, lubricants, reinforcements, fillers, modifiers…), each playing a distinctive role in determining the tribology and friction activity of the final friction material. The herein reported work presents inorganic “alkali-activated”-based materials suitable for the production of alternative brake linings (i.e. brake pads), by means of an unconventional low-temperature wet process. Exploiting the hydraulic activity of specific components when exposed to an alkaline environment, such peculiar inorganic materials are capable of coming to a complete hardening without the need of traditional high-temperature energivorous procedures.
Viewing 241 to 270 of 15895