ICAF 2009, Bridging the Gap between Theory and Operational Practice


Book Description

The 31st Conference and the 25th Symposium of the International Committee on Aeronautical Fatigue will be hosted in Rotterdam, The Netherlands, by the National Aerospace Laboratory NLR, under the auspices of the Netherlands Association of Aeronautical Engineers NVvL, the Technical University of Delft and Stork Fokker AESP B.V. These Proceedings will consist of reviews of aeronautical fatigue activities presented by the national delegates of the 14 member nations of ICAF. It will also contain specialist papers presented by international authors with design, manufacturing, airworthiness regulations, operations and research backgrounds. The papers will be based on the theme “Bridging the gap between theory and operational practice”.




Hot work tool steel in laser powder bed fusion: from parameter optimization to quality monitoring in industrial application


Book Description

This dissertation thesis focuses on applying the powder bed fusion with laser beam (PBF-LB) technology on hot work steel. It aims at achieving comparable properties with the products from the traditional manufacturing route. Using the reference powder H13, the influence of various factors, i.e., laser settings (such as laser power and scan speed) and machine settings (such as preheating) on the melting pool morphology and printing defects, is intensively investigated to check the feasibility of printing H13 components through PBF-LB technology and finally optimize the fabrication parameters for high-quality printing in lab-scale size. Furthermore, the consecutive research on the impact of the post-treatment, machine sensitivity, and powder condition provides a basis for scaling up the process and offers industrially usable products with adequate properties. Furthermore, after assessing the defects during the investigation, the classification of the defects deepens the understanding of the material-laser interaction. The mechanism for stress-lead cracks can guide the development of new types of material applied to the PBF-LB process, especially carbon-bearing steel. Finally, based on the mechanism of defect generation, the principle of the real-time defect-based monitoring system is proposed. After recognizing defects and assembling discrete points, the digital twin is established from various monitoring signals, which can be applied for on-time quality assurance without destructive testing.




Aircraft Sustainment and Repair


Book Description

Aircraft Sustainment and Repair is a one-stop-shop for practitioners and researchers in the field of aircraft sustainment, adhesively bonded aircraft joints, bonded composites repairs, and the application of cold spray to military and civil aircraft. Outlining the state-of-the-art in aircraft sustainment, this book covers the use of quantitative fractography to determine the in-service crack length versus flight hours curve, the effect of intergranular cracking on structural integrity and the structural significance of corrosion. The book additionally illustrates the potential of composite repairs and SPD applications to metallic airframes. - Covers corrosion damage assessment and management in aircraft structures - Includes a key chapter on U.S. developments in the emerging field of supersonic particle deposition (SPD) - Shows how to design and assess the potential benefits of both bonded composite repairs and SPD repairs to metallic aircraft structures to meet the damage tolerance requirements inherent in FAA ac 20-107b and the U.S. Joint Services




ICAF 2011 Structural Integrity: Influence of Efficiency and Green Imperatives


Book Description

Proceedings of the 26th Symposium of the International Committee on Aeronautical Fatigue are a widely referenced summary of advances in aeronautical design against fatigue. This is a bi-annual event and the proceedings have been published in book form for over 35 years.




Biaxial Fatigue of Metals


Book Description

Problems of fatigue under multiaxial fatigue loads have been addressed in a very large number of research publications. The present publication is primarily a survey of biaxial fatigue under constant amplitude loading on metal specimens. It starts with the physical understanding of the fatigue phenomenon under biaxial fatigue loads. Various types of proportional and non-proportional biaxial fatigue loads and biaxial stress distributions in a material are specified. Attention is paid to the fatigue limit, crack nucleation, initial micro crack growth and subsequent macro-crack in different modes of crack growth. The interference between the upper and lower surfaces of a fatigue crack is discussed. Possibilities for predictions of biaxial fatigue properties are analysed with reference to the similarity concept. The significance of the present understanding for structural design problems is considered. The book is completed with a summary of major observations.







Laser-Based Additive Manufacturing of Metal Parts


Book Description

Laser-Based Additive Manufacturing (LBAM) technologies, hailed by some as the "third industrial revolution," can increase product performance, while reducing time-to-market and manufacturing costs. This book is a comprehensive look at new technologies in LBAM of metal parts, covering topics such as mechanical properties, microstructural features, thermal behavior and solidification, process parameters, optimization and control, uncertainty quantification, and more. The book is aimed at addressing the needs of a diverse cross-section of engineers and professionals.




Additive Manufacturing, Second Edition


Book Description

The field of additive manufacturing is growing dynamically as the interest is persisting from manufacturing sector, including other sectors as well. Conceptually, additive manufacturing is a way to build parts without using any part-specific tooling or dies from the computer-aided design (CAD) file of the part. Second edition of Additive Manufacturing highlights the latest advancements in the field, taking an application oriented approach. It includes new material on traditional polymer based rapid prototyping technologies, additive manufacturing of metals and alloys including related design issues. Each chapter comes with suggested reading, questions for instructors and PowerPoint slides.




Structural Failure Analysis and Prediction Methods for Aerospace Vehicles and Structures


Book Description

This book deals with structural failure (induced by mechanical, aerodynamic, acoustic and aero-thermal, loads, etc.) of modern aerospace vehicles, in particular high-speed aircraft, solid propellant rocket systems and hypersonic flight vehicles, where structural integrity, failure prediction and service life assessment are particularly challenging, due to the increasingly more demanding mission requirements and the use of non-traditional materials, such as non-metallic composites, in their construction. Prediction of the complex loading environment seen in high-speed operation and constitutive / fracture models which can adequately describe the non-linear behaviour exhibited by advanced alloys and composite materials are critical in analyzing the non-linear structural response of modern aerospace vehicles and structures. The state-of-the-art of the different structural integrity assessment and prediction methodologies (including non-destructive structural health monitoring techniques) used for the structural design, service life assessment and failure analysis of the different types of aerospace vehicles are presented. The chapters are written by experts from aerospace / defence research organizations and academia in the fields of solid mechanics, and structural mechanics and dynamics of aircraft, rocket and hypersonic systems. The book will serve as a useful reference document containing specialist knowledge on appropriate prediction methodologies for a given circumstance and experimental data acquired from multi-national collaborative programs.




Fatigue Crack Growth Failure and Lifing Analyses for Metallic Aircraft Structures and Components


Book Description

This book provides a concise discussion of fatigue crack growth (FCG) failure and lifing analysis methods for metallic aircraft structures and components. After a reasonably concise historical review, surveys are made of (i) the importance of fatigue for aircraft structural failures and the sources of fatigue nucleation and cracking, (ii) contemporary FCG lifing methods, and (iii) the Quantitative Fractography (QF) required for determining the actual FCG behaviour. These surveys are followed by the main part of the book, which is a discussion, using case histories, of the applicabilities of Linear Elastic Fracture Mechanics (LEFM) and non-LEFM methods for analysing service fatigue failures and full- and sub-scale test results. This discussion is derived primarily from the experiences of the Defence Science and Technology Group in Melbourne, Australia, and the Netherlands Aerospace Centre, Marknesse, the Netherlands.