航空发动机机匣加工变形分析与控制

航空发动机是飞机的动力核心,其所产生的强大推力来推动飞机快速前进。机匣是航空发动机中的重要组成部分,其主要用于承受航空发动机在工作中所产生的负载和质量惯性力,做好航空发动机机匣的设计和制造对于提高航空发动机的质量有着极为重要的意义。航空发动机机匣为了实现航空发动机的功能,其在设计中多采用的是薄壁、整体的回转结构。航空发动机机匣所使用的材料主要为钛合金、高温合金等,其硬度高、加工难度大,尤其是在航空发动机机匣机械加工的过程中所产生的变形问题直接影响着航空发动机机匣的机械加工质量。本文将在分析航空发动机机匣机械加工中变形原因的基础上对如何控制航空发动机机匣机械加工中变形问题进行分析阐述,提高航空发动机的制造质量。     

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。     

金属材料疲劳断裂数据库管理系统

金属材料的疲劳断裂性能在航空产品结构设计中是必须考虑的，它直接关系到飞机和发动机的选材和定寿。本文对已建立的金属材料疲劳断裂数据库管理系统做了介绍，它不仅对材料研究而且对结构设计都有很大帮助。     

基于五轴联动数控机床的叶轮零件加工

航空发动机是飞机的动力核心,其是工业设计、制造的集大成之作。航空发动机的叶轮是航空发动机中的重要组成部分,由于其空间结构复杂从而对航空发动机叶面的加工提出了极高的要求。在航空发动机叶轮的加工过程中主要采用的是五轴加工中心来完成对于航空发动机叶轮型面的空间加工。通过使用UG软件完成对于航空发动机叶轮的建模分析以及对于五轴加工中心程序的编制,本文将在分析航空发动机叶轮特点的基础上对如何做好航空发动机叶轮加工工艺的编制进行分析阐述。     

航空材料技术的发展与应用

航空材料及其制备技术是材料科学领域中富有创造性和开拓性的一个重要分支．是航空现代化和高科技发展的物质基础．是反映一个国家综合实力和科技水平的重要标志。先进飞机、航空发动机对材料技术的依赖性越来越大，航空材料也是航空武器的生存能力、延长寿命和提高经济可承受能力等的基础．属于优先发展、重点突破的关键技术。     

发动机低涡轴超声清洗机电气控制系统设计

航空发动机是飞机的核心部件,被喻为飞机的心脏。发动机低涡轴是航空发动机传动系统中的关键部件之一。在发动机修理过程中,需要对低涡轴进行超声清洗,除去其表面附着的物质。本文讲述了发动机低涡轴超声清洗机控制系统研究与设计。     

航空发动机故障在线监测系统的研究

航空发动机是飞机的关键设备,发动机的安全运行为飞机的飞行安全提供保障,发动机的故障一定要在第一时间进行处理,避免出现重大的飞行安全事故。因此,加强对发动机故障在线监测系统的研究是十分必要的。本文介绍了航空发动机的故障分析情况,包括故障分析和碰磨颗粒产生机理,分析了航空发动机故障在线监测原理、故障静电监测原理、故障诊断及处理。     

发动机液压导管破裂原因探讨及预防措施

航空发动机的液压导管犹如人体中的血管一样,起着非常大的作用,一旦液压导管发生破裂会对飞机发动机的正常运行造成极大的影响,重则甚至会导致飞机失事。本文作者结合自己多年工作经验对发动机导管发生破裂的原因进行分析,并简要介绍应对措施。     

航空发动机复合材料的应用与研究

由于航空工业的迅猛发展,航空发动机复合材料应运而生,本文简单介绍了航空发动机复合材料的发展状况,以及主要的发展趋势,分析了发动机材料的各自独特的特性,并突显了复合材料在航空发动机发展中重要地位,为未来航空发动机的相关研究和研发奠定基础,使航空发动机相关制造工艺上再上一个新台阶。     

航空发动机叶片加工变形分析与控制措施

航空发动机是飞机的动力之源,同时也是我国航空工业发展的重要基础。航空发动机复杂性极高,其所采用的高强度材料和极高的加工精度也给航空发动机的制造带来了不小的难题。航空发动机叶片是航空发动机中的重要组成部分,航空发动机叶片的加工精度直接影响着航空发动机的性能和工作的稳定性,然而由于航空发动机叶片所具有的复杂的空间结构和极高的几何精度给航空发动机叶片的机械加工制造带来了较大的难题,航空发动机叶片受加工变形影响使得航空发动机叶片的型面轮廓精度和表面质量极差,造成航空发动机叶片加工成品率下降。为提高航空发动机叶片加工质量,应当采取有效的措施消除机械加工中的残余应力,将航空发动机叶片变形控制在合理的范围内,提高航空发动机叶片的加工精度。     

Mo‐Si‐B Alloys for Ultrahigh‐Temperature Structural Applications

A continuing quest in science is the development of materials capable of operating structurally at ever‐increasing temperatures. Indeed, the development of gas‐turbine engines for aircraft/aerospace, which has had a seminal impact on our ability to travel, has been controlled by the availability of materials capable of withstanding the higher‐temperature hostile environments encountered in these engines. Nickel‐base superalloys, particularly as single crystals, represent a crowning achievement here as they can operate in the combustors at ～1100 °C, with hot spots of ～1200 °C. As this represents ～90% of their melting temperature, if higher‐temperature engines are ever to be a reality, alternative materials must be utilized. One such class of materials is Mo‐Si‐B alloys; they have higher density but could operate several hundred degrees hotter. Here we describe the processing and structure versus mechanical properties of Mo‐Si‐B alloys and further document ways to optimize their nano/microstructures to achieve an appropriate balance of properties to realistically compete with Ni‐alloys for elevated‐temperature structural applications.     

航空发动机高温材料的研究现状

概述了航空发动机高温材料的研究现状，指出在进一步挖掘传统高温合金潜力的基础上，应加快陶瓷基复合材料、碳／碳复合材料等新型高温材料的研究。     

Neu entwickelte TiAl‐Basislegierungen für den Leichtbau von Triebwerks‐ und Motorkomponenten – Eigenschaften,Herstellung, Anwendung

Newly Developed TiAl Base Alloys for Lightweight Components in Jet Engines and Internal Combustion Engines – Properties, Production, Application Titanium aluminides are a most promising high temperature materials alternative to conventional heat‐resistant steels and superalloys for high‐performance automotive and aircraft engine applications. Intermetallic TiAl base alloys offer striking advantages for high temperature and mechanical loading applications. The specific weight of about 3.8 ‐ 4.1 g/ccm is low, the oxidation and burn resistance at temperatures up to 800 °C are good. The elastic stiffness is high and the temperature strength is enhanced. Feasible applications in combustion engines are valves, pistons and exhaust gas turbocharger rotors. Blades, vanes and discs for jet engines are under development, as well. Due to the extraordinary high specific Young’s modulus (ca. 46 GPa ccm/g) and 0.2 %‐yield strength up to 1 GPa of the TiAl base alloys in the as‐extruded state some applications at lower temperatures have also been taken into consideration, e.g. connecting rods and piston pins. The paper reviews constitutional related properties of the advanced TiAl base alloys with the respect to the industrial manufacturing of components and structural applications.     

Research on the frontiers of materials science: The impact of nanotechnology on new material development

Materials continue to play a dominant role in our society, as they have through the millennia. The developments in nanotechnology provide a unique opportunity to not only develop new classes of materials but also do so in harmony with a goal of sustainable development. There is, however, a large gap between the promise of nanotechnology and its integration into a new generation of nano-enabled products. The first half of this paper focuses on the promise of nanotechnology by exploring a novel, self-assembly based technique for the production of structural ceramics, which have the potential to dramatically affect a range of products such as power turbines and aircraft engines. In the second half of the paper examines some of the challenges in setting up a nano-engineered value chain, which is critical for a new generation of nano-enabled products.     

Processing and Applications of Intermetallic γ‐TiAl‐Based Alloys

Development and processing of high‐temperature materials is the key to technological advancements in engineering areas where materials have to meet extreme requirements. Examples for such areas are the aerospace and spacecraft industry or the automotive industry. New structural materials have to be “stronger, stiffer, hotter, and lighter” to withstand the extremely demanding conditions in the next generation of aircraft engines, space vehicles, and automotive engines. Intermetallic γ‐TiAl‐based alloys show a great potential to fulfill these demands.     

Improvement of Creep and High Temperature Tensile Properties by Adding W to Orthorhombic Ti2AlNb-Based Alloys

The Orthorhombic Ti2AlNb-based alloys (O alloys) are potential high temperature materials for applications in aircraft engines for their high specific strength. In this paper, with the purpose of enhancing the mechanical properties, W is added to O alloys as the quarternary alloying element. The effects of W additive on the high temperature tensile properties and creep resistance are investigated. The effects of boron doping on these properties are also studied.     

航空发动机高温声衬材料的研究现状

分析了用来吸收航空发动机内风扇旋转噪声及燃烧噪声的高温声衬的工况,并综述了国内外航空发动机高温声衬材料的研究现状.重点介绍了蜂窝结构声衬、微穿孔板声衬、金属纤维声衬和纤维增强陶瓷声衬材料,指出在进一步挖掘传统高温声衬材料潜力的基础上,应加快金属纤维材料这一新型声衬材料的研究.根据金属纤维材料良好的综合性能和航空发动机内的特殊使用环境,金属纤维材料应用在航空发动机内作为高温声衬材料还有很大的发展前景.     

A copula-based quantified airworthiness modelling for civil aircraft engines

The aircraft engine serves as the core system of an aircraft and operates under extreme conditions, requiring high reliability and absolute safety. The design, manufacturing, and after-sales services of aircraft engines are complex processes. To ensure safety and performance, maintenance checks are performed periodically and hierarchically throughout the engine’s life-cycle. Among these checks, shop visit (SV) heavy maintenance checks play a crucial role but are also costly, especially when they occur unexpectedly and unplanned. Analysis of the maintenance logbook, recording aviation operations, reveals a significant occurrence of unplanned SVs, which may be attributed to the existing maintenance policy based on a single time-definition. To address this issue, this paper seeks to establish a novel approach to quantifying airworthiness through copula modelling, which combines two time-definitions: the flying hour (FH) and the flying cycle (FC). This approach is unique in the aviation industry. By employing the Gumbel copula with the generalized extreme value (GEV) distribution as the marginal distribution, and utilizing non-parametric association measurement parameter estimation, the quantified airworthiness of civil aircraft engine fleets across multiple product lines can be effectively modeled. This research provides valuable insights into optimizing maintenance policies and enhancing the reliability and safety of aircraft engines.     

Achievements in Commercial Production of PM Disks and Shafts for Aircraft Engines in Russia

The paper shows stages of development of Ni-base superalloy powder metallurgy in Russia, including modifying of the alloys, with the reference to this new technology, production, testing and flying service of turbine disks in various aircraft engines. Histograms plotted from the results of mechanical property testing are presented. Prospects of application of PM Ni-base superalloys in production of aircraft engines are shown.