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1

Nanocomposites of nanocarbon functionalized carbon fibers — manufacturing to methodological applications

Kausar Ayesha, Ahmad Ishaq

Advances in Materials Science

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2024

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Vol. 24, nr 1(79)

46--71

EN

Carbon fibers have been technically applied in high performance materials and industrial scale applications. Importantly, carbon fiber reinforced composite materials have found applications in aerospace industries. These properties of carbon fiber reinforced composites depend upon the carbon fiber features such as length, orientation, surface properties, adhesion with matrices, etc. To improve the surface properties of carbon fibers and adhesion and interactions with polymers, fiber modification has been suggested as an efficient approach. Carbon nanoparticle or nanocarbon functionalized carbon fibers have been manufactured using various facile physical and chemical approaches such as electrospraying, electrophoretic deposition, chemical vapor deposition, etc. Consequently, the modified carbon fibers have nanocarbon nanoparticles such as graphene, carbon nanotube, nanodiamond, fullerene, and other nanocarbons deposited on the fiber surface. These nanocarbon nanoparticles have fine capability to improve interfacial linking of carbon fibers with the polymer matrices. The chemical vapor deposition has been adopted for uniform deposition of nanocarbon on carbon fibers and chemical methods involving physical or chemical modification have also been frequently used. The resulting advanced epoxy/carbon fiber/nanocarbon composites revealed improved tensile and physical profiles. This review basically aims manufacturing and technical aspects of polymer/fiber/nanofiller nanocomposites toward the development of high performance structures. The resulting morphology, strength, modulus, toughness, thermal stability, and other physical features of the nanocarbon functionalized carbon fibers have been enhanced. In addition, the fabricated polymer/fiber/nanofiller nanocomposites have fine interfacial adhesion, matrix-nanofiller-filler compatibility, and other characteristics. The application areas of these nanomaterials have been found wide ranging including the strengthened engineering structures, supercapacitors, shape memory materials, and several others.

2

Aerospace 3D textile preform analysis: experimental and mesomodeling

Saboktakin Abbasali, Izmir Hossein Safaei

Composites Theory and Practice

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2023

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R. 23, nr 3

118--122

EN

For the purpose of predicting how textile preforms affect the quality of the composite material and its performance, the stitched textile preform must be characterized. Experimental compaction analysis and finite element analysis of textile preforms are the main subjects of this paper. The formability parameters of a preform can be changed by the stitching process, according to research on the mechanical properties of preforms conducted during compression testing. The loaddeformation response, which is depicted in detail, had the greatest influence on preform deformation. Less fiber bundle undulation in the plane direction and more stitching thread undulation in the thickness direction were observed during compression of the stitched preform, whereas the stitching thread improved the resistance of the preform to compression loading.

3

Leading-edge polymer/carbonaceous nano-reinforcement nanocomposites — opportunities for space sector

Kausar Ayesha, Ahmad Ishaq

Advances in Materials Science

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2023

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Vol. 23, nr 4(78)

99--122

EN

Carbonaceous or nanocarbon nano-reinforcement nanocomposites have been found as emergent candidates for aerospace industry. Consequently, the multifunctional nanocomposites have been fabricated using marvelous nanocarbon nanostructures like graphene, carbon nanotube, fullerene, carbon black, etc. Manufacturing techniques have also been engrossed for the formation of high performance engineering nanocomposites having fine strength, heat stability, flame resistance, and other space desired features. These practices include solution, in situ, and melt procedures, on top of specific space structural design techniques, for the formation of aerospace structures. The aerospace related material property enhancements using various carbonaceous nano-reinforcements depends upon the type of nanocarbon, dimensionality, as well as inherent features of these nanostructures (in addition to the choice of manufacturing methods). Furthermore, carbon nano-reinforcements have been filled, besides carbon fibers, in the epoxy matrices. Nanocarbon coated carbon fibers have been filled in epoxy resins to form the high performance nanomaterials for space structures. The engineering features of these materials have been experiential appropriate for the aerospace structures. Further research on these nanomaterials may be a key towards future opportunities in the aero systems. Additionally, the explorations on structure-property relationships of the carbonaceous nanocomposites have been found indispensable for the development of advanced aerospace structures.

4

An Analysis of the Spanish Aerospace Sector: the Case of the Start-Up Ecosystem in Madrid

Morillas-Guerrero Juan José

Transactions on Aerospace Research

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2022

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Nr 4 (269)

37--47

EN

After launching the First Survey on the Spanish aerospace industry, important results were obtained, which helped to delve into the roots of the digital transformation (DT) of this sector, focussing on the Madrid region (Spain). From this type of study, which had not been carried out until now at the regional level, extremely interesting data have emerged that allow us to define the situation of Madrid companies in the aerospace sector. We have characterised and quantified the influence of what we have called ‘transformative enablers’. We have also analysed their relationships with the general characteristics of the companies, such as location, number of employees, legal form or type of company. We also obtained interesting conclusions about the role of respondents within organisations to discover the ‘capillarity’ of their situations and thus understand the degree of DT in terms of whether they achieve the so-called Industry 4.0 (Fourth Industrial Revolution) specifications. Finally, we have carried out a monographic study of the disruptive innovations within the start-up ecosystem to understand its definition and scope in the aerospace industry as a precursor of the latter’s DT.

5

The Use of Additive Manufacturing for Production of Commercial Airplane Power Plants Components: A Review

Węgrzyn Nicolas

Safety & Defense

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2022

|

2

36--45

EN

The purpose of this paper is to provide an overview of the available Additive Manufacturing (AM) technologies widely documented in many scientific papers and to attempt to answer the question of whether this technology could be used in the optimization of geometry for aircraft engine parts. The core research method in this article is based on the analysis of the scientific literature related to Additive Manufacturing gathered over the past two decades. The discussion starts with a review of various technological solutions, including Powder Bed Fusion (PBF), Direct Energy Deposition (DED) or Electron Beam Melting (EBM). The technological schemes of the processes or their differences are shown, as well as the advantages, disadvantages, and development opportunities. The article also attempts to divide AM technologies in terms of the materials used. The purpose of this approach is to simplify technology selection from an engineering point of view. At the end of this article, industrial ‘in-use’ applications in safety orientated aerospace market are overviewed. As a result of the literature analysis, an attempt is made to prove that modern additive technologies could be used to optimize integrated and complex structures like air bleeds in high pressure compressors of airplane powerplants.

6

Review of Modern Helicopter Constructions and an Outline of Rotorcraft Design Parameters

Kachel Stanisław, Rogólski Robert, Kocjan Jakub

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

|

2021

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Vol. 12, Nr 3 (45)

27-52

EN

This work contains the results of a modern helicopter construction analysis. It includes the comparison of almost seventy rotorcraft constructions in terms of size in line with EASA requirements – large and small helicopters. The helicopters are also divided because of a mission purpose. The proposed division for large aircrafts is: transport, multipurpose, attack and for small aircrafts: observation, training, and utility. The aircraft construction features are described. Average dimension values of airframes and rotors are shown. Helicopter rotor arrangements are presented in terms of an operational purpose. Next, the rotorcraft design inputs are described. The mathematical formulas for design inputs are given. The ratios are calculated and gathered for the compared aircrafts. Correlation between the analysed parameters is presented on charts. Design inputs are also presented in the paper as a function of MTOW. The function trends are determined to provide an evaluation tool for helicopter designers. In addition, the parameters are presented as possible optimisation variables.

PL

Praca zawiera wyniki analizy współczesnych konstrukcji śmigłowcowych. Obejmuje porównanie prawie siedemdziesięciu konstrukcji wiropłatów podzielonych ze względu na rozmiar: zgodnie z wymaganiami EASA – duży i mały śmigłowiec. W ramach rozmiaru statki powietrzne zostały podzielone ze względu na cel misji. Proponowany podział dla dużych śmigłowców to: transportowe, wielozadaniowe i szturmowe, natomiast dla małych: obserwacyjne, szkoleniowe, użytkowe. Wyszczególniono najważniejsze cechy konstrukcyjne wiropłata. W pracy zaprezentowano średnie wartości wymiarów płatowców i wirników. Przedstawiono również układ wirników śmigłowca pod kątem przeznaczenia operacyjnego. Finalnie opisano parametry projektowe przydatne w projektowaniu wstępnym. Parametry opisano za pomocą wzorów matematycznych oraz dla każdego z nich zaprezentowano na wykresie zebrane dane statystyczne. W artykule pokazano zależność parametrów w funkcji maksymalnej masy startowej statków powietrznych. Wyznaczono trendy w celu dostarczenia narzędzi do oceny projektowanych śmigłowców. Dodatkowo przedstawiono możliwość wykorzystania parametrów jako zmiennych optymalizacyjnych.

7

The potential of SLM technology for processing magnesium alloys in aerospace industry

Kurzynowski T., Pawlak A., Smolina I.

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 1

327--339

EN

Selective Laser Melting (SLM) of magnesium alloys is the technology undergoing dynamic development in many research centres. The results are promising and make it possible to manufacture defect-free material with better properties than those offered by the manufacturing technologies used to date. This review aims to evaluate present state as well as main challenges of using Laser Powder Bed Fusion (L-PBF) for processing magnesium alloys as an alternative way to conventional technolo-gies to manufacture parts in the aerospace industry. This literature review is the first one to outline information concerning the potential to use magnesium alloys in the aerospace industry as well as to summarise the results of magnesium alloy pro-cessing using AM technologies, in particular L-PBF. The available literature was reviewed to gather information about: the use of magnesium alloys in the aerospace industry-the benefits and limitations of using magnesium and its alloys, examples of applications using new processing methods to manufacture aerospace parts, the benefits and potential of using L-PBF to process metallic materials, examples of the use of L-PBF to manufacture aerospace parts, and state-of-the-art research into L-PBF processing of magnesium and magnesium alloys.

8

Global aerospace industry risks

Balcerzak T.

Zeszyty Naukowe. Transport / Politechnika Śląska

|

2019

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z. 102

05--27

EN

The global Aerospace industry is expected to improve in 2018 as its revenue is predicted to rise by 4.1% , doubling last year’s 2.1% growth. The recovery of global gross domestic product (GDP), stable commodity prices, and increased passenger travel demand are likely to ramp up growth in the commercial aircraft sector in 2018. This article reviews the performance of the aerospace industry in 2017 and 2018 and speculates its growth in the incoming years. It also outlines the performance across the major aerospace markets and discusses trends that will impact the industry. The article forecasts the mergers and acquisitions activity in 2018 that lays the foundation for further growth in this space. Key findings are: • Commercial aircraft sector revenues are expected to grow by 4.8% as production levels are likely to be robust while the defence sector revenues are likely to record 3.6% growth as the US defence budget recovers after experiencing multi-year declines. • The spiralling demand for passenger travel is driving commercial aircraft production and is responsible for the record high backlog of 14,215 units at the end of 2017. • In 2018, global Mergers and Acquisitions (M&A) activity is expected to remain strong in the aerospace sector, being driven by pricing pressures from aircraft OEMs and their expansion of high-margin aftermarket services. This has pushed suppliers to consolidate for scale and cost-effectiveness.

9

Progress in Digital Industrial Radiology. Pt. 2, Computed tomography (CT)

Ewert U., Fuchs T.

Badania Nieniszczące i Diagnostyka

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2017

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nr 1-2

7--14

EN

Part 1: Film Replacement and Backscatter Imaging. The related paper was published in Vol 1-2/2016 of this journal. Part 2: Computed tomography (CT). Applications cover the range from nano-meter to meter scale. New specialized high energy CT devices have been laid out for inspection of large building structures or complete cars before and after crash tests. The scope of typical CT applications changes from flaw detection to dimensional measurement in industry substituting coordinate measurement machines. First applications of at line or in line inspection in production lines of car industry are discussed. CT is applied for a variety of applications, where selected areas as e.g. plant and food research in outlined. Mobile computed tomography is applied for in-service radiographic crack detection and sizing of welded pipes in nuclear power plants and for NDT of large CFRP structures of airplanes. Part 3: Micro Radiography and Micro CT. To be published in this journal.

PL

Podobnie jak w przypadku zakończonego sukcesem wdrożenia fotografii cyfrowej, bardzo istotne zmiany można zaobserwować także w cyfrowej radiologii przemysłowej. Niniejsza praca jest podzielona na 3 części: Część 1: Następca błony radiograficznej i obrazowanie za pomocą rozproszenia wstecznego – publikacja ukazała się w wydaniu Nr1-2/2016 tego czasopisma. Część 2: Tomografia komputerowa (CT). Zastosowania tomografii obejmują obiekty o wielkości od nanometrów do metrów. Nowe dedykowane urządzenia wysokoenergetycznej tomografii komputerowej skonstruowano w celu inspekcji dużych konstrukcji budowlanych czy też całych samochodów przed i po testach zderzeniowych. Cel typowego zastosowania tomografii komputerowej uległ zmianie z detekcji wad na wymiarowanie wyrobów przemysłowych, co spowodowało zastąpienie współrzędnościowych maszyn pomiarowych. W pierwszej kolejności omówiono zastosowanie tomografii komputerowej na liniach produkcyjnych w przemyśle samochodowym. Tomografia komputerowa ma wiele zastosowań, w tym np. badanie roślin i żywności. Przenośne tomografy komputerowe wykorzystywane są do wykrywania defektów i wymiarowania spawanych rur w elektrowniach jądrowych, a także do inspekcji dużych elementów konstrukcji lotniczych wykonanych z kompozytów węglowych. Część 3: Mikroradiografia i mikrotomografia komputerowa.

10

Dobór procesu kondycjonowania próbek zgodnie z wymaganiami kwalifikacji kompozytów polimerowych do zastosowań w konstrukcjach lotniczych

Kaczorowska E.

Prace Instytutu Lotnictwa

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2016

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Nr 3 (244)

83--89

PL

W artykule przedstawiono sposób kondycjonowania próbek wedlug stosowanych na świecie regulacji dotyczących kwalifikacji kompozytowych materiałów lotniczych (FAA – Federalna Administracja Lolnictwa - Federal Aviation Administration, EASA - Europejska Agencja Bezpieczeństwa Lotniczego - European Aviation Safety Agency, MIL-HNBK – Podręcznik Wojskowy - Military Handbook). Przeprowadzono proces kondycjonowania próbek w komorze klimatycznej o zadanej temperaturze oraz wilgotnosci zgodnie z normq ASTM D5229. Przeprowadzono obliczenia w celu doboru parametrów klimatyzowania oraz dokonano weryfikacji stanu nasycenia próbek. Wykonane obliczenia zwróciły wartość współczynnika dyfuzji, dla badanych próbek wytworzonych w technologii bezautoklawowej z prepregu węglowo-epoksydowego CYTEC MTM46. Znajomość współczynnika dyfuzji pozwolila zmniejszyć czas interwałowego ważenia o 30 %. Dokonano także selekcji rodzajow substancji chemicznych, które mogą mieć wpływ na trwałość materiału kompozytowego. Podsumowano i porównano stosowane procesy kondycjonowania według regulacji stosowanych do kwalifikacji materiałów lotniczych, oraz przeprowadzony process klimatyzowania według normy ASTM D 5229.

EN

Kind of the samples conditioning, used on the world according to the regulations of the qualifications of composite aerospace materials (FAA - Federal Aviation Administration, EASA- European Aviation Safety Agency, MIL-HNBK - Military Handbook), is presented in this article. The process of conditioning the samples in a climate chamber set temperature and humidity in accordance with the ASTM D5229 was carried out. Calculations were carried out in order to select the parameters of conditioning and a verification of the saturation of the samples. Types of chemicals that may affect the durability of the composite material have also been selected. The processes of conditioning according to the regulations applicable to the qualification of aerospace materials and conditioning process according to the ASTM D 5229 were summarized and compared. Keywords: samples conditioning, qualifications of materials, composite, aerospace.

11

Management changes in MRO business through product lifecycle

Sivusuo J., Takala J.

Management and Production Engineering Review

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2016

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Vol. 7, No. 3

87--93

EN

Nowadays organizations and entire industries have faced the challenges of globalization and rapid technological development. These changes have brought new kind of competition and it has shaped and mixed organizations traditional business logic. This research is based on multiple case studies where the focus is on management changes through product lifecycle management. Emphasis is on MRO (Maintenance, repair, overhaul) providers and how they implement dynamic capabilities through product life cycle management. MRO is abbreviation for Maintenance, repair and overhaul and it is a commonly used in Aerospace industry. The study identifies several products in various stages of the life-cycle and thus identify the essential changes related to management. The stages that study identifies are Learning phase, Productisation phase and PBL phase. These phases can be used for clarifying dynamic capabilities in MRO markets.

12

Approach to Critical Crack Opening Displacement Modeling of Damage in Metal Sheets after Composite Patch Bonded Repair

Sałacinski M., Leski A., Stefaniuk M.

Fatigue of Aircraft Structures

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2016

|

Iss. 8

104--110

EN

The paper proposes a method of calculating the maximum displacement in the aircraft metal structure repaired by CPBR (bonded composite patch repair). The calculations were made based on specimens. The specimens were prepared according to the current requirements used in aviation. The 2024-T3 alloy metal sheet was a structure. To repair the structure used the boron-epoxy composite patch in prepreg technology was used. The metal structure was modeled as an isotropic elastic body. The metal structure coated with the composite patch was modeled as an orthotropic structure. Based on this, the stress was determined in the metal structure. The size opening displacement in the metal structure was determined based on the model of linear elastic fracture mechanics for the plane stress state. The calculation results were verified by measuring the displacement in laboratory conditions. The laboratory tests made it possible to demonstrate the accuracy of the proposed approach.

13

A study on superplastic forming of multiple sheet with integral stiffeners

Lee H.-S., Yoon J.-H., Yoo J.-T., Choi J.-U.

Inżynieria Materiałowa

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2014

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Vol. 35, nr 2

166--170

EN

Blow molding process is one of the common manufacturing processes in plastic and glass industry. The advantages include low cost of the tool and ability to mold complex part. In metallic system, a similar process like superplastic forming has been widely used in aerospace industry, since it is possible to fabricate very thin part and hence lightweight structure. The present study demonstrates superplastic blow forming process with IN718 and titanium and aerospace components with a complex shape which were successfully manufactured. These metals have been used for high temperature application like lightweight propulsion systems. It is interesting to notice high value of strain rate sensitivity obtained for titanium alloy, while this for IN718 was relatively low at the forming temperature. The result shows that the developed technology to design high temperature superplastic forming by the finite element method can be applied for nearly net shape forming 2-sheet, 3-sheet and 4-sheet stiffened panels for lightweight component of aerospace structure.

PL

Proces formowania przez nadmuchiwanie jest jednym z najpowszechniejszych procesów w przemyśle tworzyw sztucznych i szkła. Zalety tego procesu polegają na niskich kosztach narzędzi oraz zdolnościach do formowania złożonych części. W systemach metalicznych, podobny proces – formowanie nadplastyczne jest szeroko stosowane w przemyśle lotniczym, ponieważ umożliwia otrzymywanie bardzo cienkich grubości materiału a więc struktur lekkiej konstrukcji. Przedstawione studium demonstruje nadplastyczne formowanie przez nadmuchiwanie z wykorzystaniem IN178, tytanu oraz otrzymanie w ten sposób lotniczych komponentów o złożonym kształcie. Te metale są wykorzystane w aplikacjach wysokotemperaturowych takich jak lekkie systemy napędowe. Należy zwrócić uwagę na dużą wrażliwość na szybkość odkształcenia stopów tytanu, podczas gdy dla IN718 jest ona relatywnie niska w temperaturze formowania. Wyniki te pokazują, że rozwinięta technologia procesu projektowania wysokotemperaturowego formowania nadplastycznego za pomocą MES może być stosowana w postaci 2, 3, 4 arkuszowych paneli usztywniających dla lekkich komponentów przemysłu lotniczego.

14

Managing DO-178 compliance with IBM Rational platform. Leverage state-of-the-art best practices to develop avionics software

Çakmak M. K.

Journal of KONBiN

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2013

|

No. 1 (25)

59--74

EN

DO178 is a standard for avionic software for the aerospace industry which can be used as a guidance to determine if the software product will perform reliability in airborne environment. The standard has 5 different certification levels each of which has a certain set of objectives. The certification levels are determined depending on how critical the system or subsystem is. To address DO-178 objectives, companies need a defined systems and software engineering process that can delineate workflows, inputs, outputs, roles and responsibilities. The major objectives outlined in the DO-178 standard include; Requirements engineering Design and development. Validation and verification Engineering tasks, such as configuration and change management In this presentation, we will try to explain the main principles of the DO178 standard very briefly and try to give an insight about how the objectives of this standard can be satisfied.

PL

DO-178 jest normą dla oprogramowania awionicznego dla przemysłu lotniczego, która może być stosowana w charakterze wytycznych w celu ustalenia, czy oprogramowanie będzie wykazywać niezawodność w środowisku lotniczym. Norma ma pięć różnych poziomów certyfikacji, z których każdy ma określony zestaw celów. Poziomy certyfikacji są ustalone w zależności od tego, na ile krytyczny jest system lub podsystem. W celu spełnienia celów DO-178 przedsiębiorstwa potrzebują zdefiniowanych systemów i procesu tworzenia oprogramowania, które mogą prezentować przebiegi procesów, wartości wejściowe, wyjściowe, role i zakresy odpowiedzialności. Główne cele nakreślone w normie DO-178 obejmują: ustalenie wymagań, projektowanie i rozwój, walidację i weryfikację, zadania inżynierskie, takie jak konfiguracja i zarządzanie zmianami. W niniejszej prezentacji spróbujemy wyjaśnić w skrócie główne zasady normy DO-178 oraz sposób, w jaki cele tej normy mogą zostać spełnione, a odpowiednie poziomy certyfikacji osiągnięte dla tworzonego systemu lub podsystemu. and the relevant certification level can be achieved for a system or subsystem under development.

15

Using Sandblasting and Sol Gel Techniques for the Preparation of a Metal Surface and Their Effects on the Durability of Epoxy-Bonded Joints

Sałaciński M., Zabłocka M., Synaszko P.

Fatigue of Aircraft Structures

|

2012

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Iss. 4

94--99

EN

The epoxy-bonded joints are widely employed in aerospace in the Composite Patch Bonded Repair (CPBR) method used for repair metallic and composite structures. The properties of epoxy usually meet the mechanical and environmental requirements, but the durability of bonded joints depends also on the surface preparation. The most common techniques used for the surface preparation are Forest Product Laboratory’s (FPL) technique and Phosphoric Acid Anodizing (PAA). Both methods ensure very good adhesion but they have some disadvantages. They require the application of toxic and aggressive acids, dangerous for the operator. Also, the use of acids for cleaning the surfaces can cause corrosion. The sandblasting treatment of metal surfaces ensures quite good adhesion. This technique requires neither specialist equipment nor the use of toxic substances. Recommended by the Royal Australian Air Force (RAAF) the technique is also used by the Air Force Institute of Technology. Sol Gel is a new product developed for the treatment of metal surfaces before bonding. It is not hazardous for the operator and it does not cause corrosion due to its specific chemical composition. The article describes the behavior of bonded joints between two metal surfaces prepared using sandblasting and Sol Gel. The investigations were carried out in various environment conditions according to the ASTM Standards.

16

A new diagnosing method of the internal structure of the titanium fan of a jet engine with laser ultrasonics

Swornowski P.

Metrology and Measurement Systems

|

2011

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Vol. 18, nr 3

441-451

EN

Advanced metallic material processes (titanium) are used or developed for the production of heavily loaded flying components (in fan blade construction). The article presents one process for diagnosing the blade interior by means of laser ultrasonography. The inspection of these parts, which are mainly made of titanium, requires the determination of the percentage of bonded grain sizes from around 10 to 30 žm. This is primarily due to the advantages of a high signal-to-noise ratio and good detection sensitivity. The results of the research into the internal blade structure are attached.

17

Precise model of HSC Machining Centre for aerospace parts machining

Jedrzejewski J., Kwasny W., Kowal Z., Modrzycki W.

Journal of Machine Engineering

|

2008

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Vol. 8, No. 3

29--41

EN

This article shows the aspects of precise modelling of precise High-speed Machining Centres for High-Speed Cutting (HSC) of parts used in the aerospace industry. The main focus was made on the thermal errors having a dominant influence on the precision of machining. Main assumptions for a hybrid thermal model of a centre thermal behaviour have been stated, taking into account the characteristics of heat sources. On the example of a 3-axis machining centre, measured runs of heating up and heat displacements have been shown, compared to these determined with the use of simulations of a behaviour in assumed working conditions. A special attention was drawn to the phenomena taking place in motorspindles, as well as to the displacements of a spindle face during high rotational speeds of spindles and step changes of rotational speeds. The significance and influence of the bearing preload and centrifugal forces on the spindle axial displacements was shown, which is decisive on the precision of part machining. Additionally, it was shown that the important component of a machining error is an error of spindle position identification by means of a linear encoder, resulting from the thermal deformation of a centre body, to which a quartz linear encoder is fixed.

18

Object-oriented approach to interactive analysis of structures in virtual prototyping

Szewczyk Z.

Research Bulletin / Warsaw University of Technology, Institute of Aeronautics and Applied Mechanics

|

1998

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nr 8

11-24

EN

The paper presents a novel, object-oriented approach to structural modeling and analysis to enable interactive, virtual prototyping in the next generation of the design environment. It is believed that the interactivity of analysis of build-up structures can only be achieved by reusing results of component analyses, therefore, the applicability of data-based analysis to the 0-0 approach is investigated in this paper. An object in the 0-0 approach is a neurocomputing model of a structural component developed for a given set of parametrized design variables, loading, and "smart" connectors. Such connectors define how the given component is connected to the assembly, and what is the validity of such a connection. Since component models can be subject to affine transformations, a family of similar structural components is available for modeling. Neurocomputing models are used to enable data-based analysis, because they can relate any design variables and load conditions to the selected system response. The applicability of feed-forward and feature-sensitive neural nets is examined in this context. Object-oriented modeling is illustrated with design of linear and geometrically nonlinear beams with a single-point (SP) connector, and a multipoint (MP) connector is used for a selected problem involving the Next Generation Space Telescope (NGST).