Aspects of TBC service experience in aero engines

The frame conditions to apply advanced materials technologies in aero engines are envisaged from view point of an aircraft operator and performer of allocated maintenance repair and overhaul activities. Main targets are the reliable operation of the parts, the steady ecological improvement during operation and the reduction on overall cost per flight hour based on increased knowledge. The application of Thermal Barrier Coatings (TBCs) may contribute to reach these goals. They may – for example – add to optimised operation by reducing fuel consumption and by protecting important engine parts. The principles of a long term engine parts operation and repair philosophy are outlined to clarify the property requirements for reliable engine operation. Typical TBC‐protected components within actually operated civil aero engines are described. Silicate deposition on a HTP Blade and erosive attack of TBC is introduced exemplarily. A repair sequence to counteract surface degradation is introduced.     

我国大型客机先进复合材料技术应对策略思考

航空工业发展, 尤其新一代大型民用飞机的研制, 带动并促进了复合材料技术的飞速发展。先进复合材料在新一代大型民用飞机上的成功应用, 为未来民用飞机的发展确立了新的标准和市场准入门槛。欧美先后制订并实施了一系列航空复合材料研究计划促进复合材料技术的发展, 并取得成功。国内复合材料技术经过多年发展虽然有一定基础, 但在原材料开发、产品设计、制造及质量监控、技术转化等许多方面与国外相比还存在较大差距。在国家确立大型飞机重大研究专项的背景下, 为满足我国大型客机研制的需要, 大力促进我国复合技术水平快速提升, 我们要从发展策略、组织管理、技术研究和产业发展等方面开展工作, 实现我国复合材料技术的跨越式发展。      

Prospects of Supercritical Fluids in Realizing Graphene‐Based Functional Materials

Supercritical‐fluids science and technology predate all the approaches that are currently established for graphene production by several decades in advanced materials design. However, it has only recently been proposed as a plausible approach for graphene processing. Since then, supercritical fluids have emerged into contention as an alternative to existing technologies because of their scalability and versatility in processing graphene materials, which include composites, aerogels, and foams. Here, an overview is presented of such materials prepared through supercritical fluids from an advanced materials science standpoint, with a discussion on their fundamental properties and technological applications. The benefits of supercritical‐fluid processing over conventional liquid‐phase processing are presented. The benefits include not only better performances for advanced applications but also environmental issues associated with the synthesis process. Nevertheless, the limitations of supercritical‐fluid processing are also stressed, along with challenges that are still faced toward the achievement of the great expectations from graphene materials.     

Anwendungsfelder moderner Oberflächentechnik bei Anbietern oberflächentechnologischer Dienstleistungen

Concerning the transfer of results from research and development into commercial business practice for small and middle sized enterprises, offering surface‐technological services, the situation is generally better than aspected. This is the conclusion arrived at by the Institut for knowledge transfer at the University of Bremen (IfW) after carrying out a random analysis of the enterprises offering surface technology services. The study is a component of the project “Technology transfer surface technology”, which is accomplished on behalf the Federal Ministry for education and research (BMBF) by the VDI Technologiezentrum. Two thirds of the enterprises asked plan to introduce new procedures or modernize and/or supplement existing procedures in the next two years. All the same one third plans on top of this to use new layer materials. At present the situation regarding the application of modern surface technology, shows that the correct application of the surface and layer technologies bears fruits. The degree to which thermal spraying and the PVD and CVD techniques are applied has increased. Old procedures are rapidly being displaced by innovative and more pollution free procedures – especially in the field of thermal treatment. The technological developments planned for the next two years by the enterprises asked show that the degree with which the technologies specified above are spreading will continue to increase. Also the predication as to, which industries will be ranked in the future as important customers of the surface‐technological services, is changing. While the enterprises evaluate the situation toke restrained in the electro‐technology and electronics industry. An increased demand from air and space industry is expected. Moreover a clear increase in the paper and graphic arts industry is predicted.     

复合材料在新一代大型民用飞机中的应用

新一代大型民用飞机机体结构的突出特点是广泛采用复合材料。总结了复合材料在大型民用飞机中的发展,其用量已经从1980年整机质量的4%上升到目前的50%,并广泛应用于主承力结构和复杂曲面结构。以波音787和空客A350飞机为例,分析了波音和空客公司复合材料的应用情况,发现复合材料不仅减轻了飞机的结构质量,提高了飞机结构的使用寿命,降低了飞机的维护费用,而且可以增加舱内压力和空气湿度,提高民用飞机的经济性、舒适性、环保性。复合材料取代金属和非金属等常规材料制造结构件已经成为世界民机制造业的主流趋势,这对中国自主研制的大型民用飞机的市场竞争力提出了严峻的考验,为此提出了中国在研制大型民用飞机时应用复合材料应注意的一些问题。     

聚酰亚胺/无机纳米杂化材料的研究

聚酰亚胺(PI)中引入无机纳米粒子,可弥补PI的性能缺陷(如较高的热膨胀系数和较低的吸水性),非常适合对PI改性.本文阐述了PI纳米杂化材料的制备方法,介绍了纳米杂化材料的特点及应用.     

低成本材料技术在美国新型航母上的应用研究

本文概述了美国海军金属加工中心(NMC)在2010—2011年间参与开展的新型航空母舰用先进材料、先进制造技术、先进连接技术、新型表面涂装与处理技术等方面开展的低成本材料技术研发工作所取得的进展。预测了研究成果转让给海军应用时,给航空母舰建造提高性能、降低成本所带来的巨大经济效益和社会效益。这将对我国开展舰船用先进材料及制造技术方面的研究与开发工作起重要启示作用。     

The Influence of the Constituent Properties on the Residual Strength of Glare

Aircraft manufacturers like Boeing and Airbus are currently designing new, high capacity aircraft, e.g., A3XX. To make this aircraft cost effective for the next 30 years, a strong impulse is given to the development of new technologies like the application of new aircraft materials. One of these studies investigates the feasibility of using the Fibre Metal Laminate Glare in the damage tolerance critical upper part region of the aircraft in order to reduce weight and increase safety. The present study investigates the crack resistance of Glare in case of foreign object damage as a function of the constituent's characteristics. An experimental program has been performed on Fibre Metal Laminates built up from several combinations of aluminium alloys and fibres. Especially the fracture mechanism was studied. It was found that a larger strain hardening region and a lower yield stress of the aluminium layers had a positive influence on the residual strength due to the capability of transferring high loads away from the cracked area. Increasing the stiffness and lowering the ultimate strain of the fibres reduces the residual strength, since stiffer fibres attract more load and because the final fracture is dominated by fibre failure.     

Reinforcement of the F-111 wing pivot fitting with a boron/epoxy doubler system—materials engineering aspects

Local regions in the D6ac steel F-111 wing pivot fitting suffer plastic deformation during the cold proof test employed to screen out flaws in the steel components of the airframe. This deformation produces residual stresses which can lead to a fatigue cracking problem in service. This paper describes materials engineering aspects of a programme undertaken at the Aeronautical Research Laboratory to develop an advanced fibre composite doubler system aimed at reducing the strain in these regions during the cold proof test and also to reduce cyclic strain during subsequent operation of the aircraft. The doubler system chosen is boron/epoxy (over 120 plies thick) bonded with a structural film adhesive. Aspects described include selection and characterization of composite and adhesive bonding system, doubler fabrication and application technology and evaluation of a representative doubler specimen. Use of the doubler system has been demonstrated to reduce the strain in the critical regions by over 30%, confirming design predictions.     

我国航空用变形钛合金材料

钛合金材料作为一种20世纪中叶出现并发展起来的新兴结构材料,因其具有优异的耐腐蚀性、高的比强度以及无磁性等一系列独特的优点,在航空航天等高端工业部门获得了广泛应用,目前飞机机体结构中的隔框、大梁、起落架以及航空发动机压气机匣、轮盘、叶片等承力部件大量使用钛合金材料制造。在上世纪60年代,美国、英国、前苏联等工业发达国家就已经在飞机及航空发动机制造中大量使用钛合金材料。我国钛合金材料在航空工业中的应用起步较晚,上世纪80年代开始才陆续在飞机及航空发动机制造中少量使用钛合金材料,但是进入21世纪之后,我国航空工业钛合金材料的应用水平大幅度提升。对我国目前已经进入工业化生产并在航空工业中获得工程化应用的变形钛合金材料进行了系统阐述。     

Maintenance of Glare Structures and Glare as Riveted or Bonded Repair Material

Aircraft structures constructed from new and advanced materials will become more common in the near future, starting with the use of the Fibre Metal Laminate Glare in large parts of the Airbus A-380 fuselage. These materials are primarily used because of their excellent damage tolerance properties. However, questions about maintenance and repair of such structures need to be answered before such new materials can be used. These questions include whether new and advanced materials can be repaired in a conventional way, which would not only be preferable from the operator's point of view (no change in tools, maintenance procedures, and personnel training), but also from the manufacturer's point of view (Structural Repair Manuals similar to aluminium structures). A Glare demonstrator panel has been designed and applied to an Airbus A-310 and research into the repairability of Glare has been performed to answer these questions. Apart from looking into the repairability of Glare structures, the material itself is also investigated as material for bonded repair patches. Bonded repair many times proves to be a more viable solution than conventional riveted repair due to its more efficient load transfer. Important aspects of bonded (Glare) repair are under investigation to show that bonded patch repair is not only working for the ageing aircraft of several Air Forces around the world, but is also a promising candidate for safe and cost-effective repairs to ageing and new (incidental damage) aircraft of commercial operators. This research is conducted cooperatively by Delft University of Technology and the United States Air Force Academy and has led to two real-life repairs on a C-5A Galaxy.     

航空结构材料研究进展

本文对航空系统结构材料的现状和进展，以及先进的材料和工艺对飞机和飞机发动机的进步所起的重要作用进行了全面系统的研究。本文的主要内容是关于航空和航空发动机材料，以及新材料在制造轻型结构中的作用。     

循序渐进的供应商关系管理模式

企业不可能与所有的供应商都保持伙伴关系。企业供应商关系管理需要遵循一种循序渐进的模式。对于消耗量大的关键性原材料供应商，企业应该努力与其建立相互信任的伙伴关系；对于专用件、进口件等企业需求量少但是对企业最终产品质量影响大的瓶颈物资，企业应该努力寻找替代的供应商；对于标准件、办公品等需求频繁，但是每次需求的数量不大，单项产品占用资金不大的物资，企业可以寻找第三方供应商。对于需求量大的一般性原材料的供应商，企业可以公开招标，寻求物资的价格优势。     

煤炭产业技术创新战略的探讨

在分析和探讨技术创新及其战略理论的基础上,分析了我国煤炭产业的技术创新及其战略问题,考虑到技术发展阶段差异较大的特点,先进企业的创新战略应选择率先创新与模仿创新并存,其他大多数企业则应主要采用模仿创新战略,并形成产学研相结合、主体及模式多元化的集成创新格局。     

Die Geschichte der Deutschen Vakuum‐Gesellschaft DVG e. V.

The history of the German Vacuum Society DVG e. V. – All for vacuum‐supported sciences and technologies For almost half a century, the German Vacuum Society and its preceding organizations have been supporting the research and application of vacuum‐assisted sciences and technologies, fostering the national and international exchange of scientific information and opinions in related disciplines, honoring outstanding scientific achievements and promoting training and further education in all aspects of vacuum technology. Highlights and turning points of this development are described here.     

复合材料飞机结构技术成熟度评价方法

飞机设计人员在飞机总体方案论证阶段对主要结构件进行选材时, 需要对复合材料飞机结构的技术成熟度进行评估, 以确定是否选用复合材料。借鉴技术完备等级(TRL) 标准, 提出了一个复合材料飞机结构技术成熟度定量评价方法(TEMCAS)。TEMCAS 方法将复合材料飞机结构的技术成熟度分为 8 个等级, 涵盖了复合材料结构技术从设计需求到结构应用的整个过程, 通过对波音公司复合材料机身结构技术的技术成熟度评价实例证明了其有效性。在飞机总体方案论证阶段可以利用TEMCAS 方法, 对复合材料飞机结构技术的成熟度进行定量分析, 为初步选材复合材料结构应用的决策和风险评估提供依据。      

材料的成形加工与凝固技术

从对材料成形加工技术进步的分析入手,论述了凝固技术在材料先进成形加工技术中的应用及其重要性。结合对几种凝固新技术的实例的分析指出,不论是传统材料加工过程"控形-控性（控制组织）-控制成本-控制污染"一体化新技术,还是作为新材料研制手段,凝固技术的重要性均是非常突出的。进而分析了近年来受到广泛重视的凝固过程研究的新课题及其由此可能带来的技术进步。     

复合材料结构修补技术的发展

先进复合材料在航空工业的大量应用可有效地改善飞机的性能，随着这种应用的增长以及为了更有效地使用先进复合材料，迫切需要发可靠的修理技术，本文综述了有关复合材料修补技术的发展，已有的结果表明，如采用适当的修理技术，复合材料构件可有效地修复，甚至可恢复到原来的强度。     

The design of advanced aircraft structures to resist acoustic fatigue; work in progress

Details of the current research activities in the Department of Aeronautics and Astronautics, on the response of advanced aircraft structures to acoustic loading, are presented. Both box type and sandwich structures, employing aluminium alloy, carbon fibre reinforced plastic, and GLARE composite materials, are being investigated. In order to develop design guidelines for these complex structures, it is necessary to combine theoretical predictions, using the finite element method, with experimental measurements of the structural response to random acoustic loading. Both types of structure will be tested in the Progressive Wave Tube facility at Southampton. In addition, it is hoped that a more comprehensive damping guide will be produced for the type of structure used in advanced aircraft design.     

Umformtechnologie: Prozesse – Werkstoff‐ charakterisierung – Simulation – Verifikation

Sheet forming technology – processes, materials, simulation and verification Hydroforming and Deep Drawing represent leading technologies for forming sheet metal components. The Materials Branch of the University of Duisburg‐Essen works since more than 10 years in the field of Hydroforming and showed that Hydroforming increases the strength and that the weldings of hydroformed tubes normally exhibit a same (fatigue) strength as the base material. For an improvement of the economics of hydroforming spliced tubes were considered and standard hollow nodes for tubes nodes structures were developed and a proposal was made to produce these tubes in variable tools with segments or lamellas. A significant increase in economics of Hydroforming and of Deep Drawing of components is achieved by an introduction of the principles of an integral (cooperative) development of products. At the University of Duisburg‐Essen the following stages are run through: CAD (the Material Branch uses PRO/ENGINEER®), forming simulation – for that PAM‐STAMP® (ESI) and PATRAN MARC MENTAT® (MSC) are used – FEM strength calculation and EVICD for a consideration of variable service loading. Forming simulation needs as basic material data the yield curve, the parameters of anisotropy and the Forming Limit Curve (FLC). For a determination of the FLC in Deep Drawing Tests suitable Nakazima specimens were developed by applying the principles of cooperative product development. The specimens could then successfully be validated in Deep Drawing Tests, which were instrumented by the advanced 3D‐forming‐analysis‐system AUTOGRID inProcess (VIALUX). Various other forming simulations were also performed and some general rules for the performance of forming simulations were formulated. Finally, reverse engineering is briefly discussed.