Fatigue of Ti-6Al-4V Thin Parts Made by Electron Beam Melting

Fatigue of Ti-6Al-4V Thin Parts Made by Electron Beam Melting PDF Author: Théo Persenot
Publisher:
ISBN:
Category :
Languages : en
Pages : 191

Get Book Here

Book Description
Nowadays, reducing the energy consumption is crucial for most of the industries. For transportation industries, it can be achieved through weight reduction. In this context, cellular structures turn out to be one of the most efficient solution. Thanks to the development of additive manufacturing, producing such complex geometries is no longer an issue. However, their use will remain limited as long as their fatigue performances are not known. This PhD work aimed at understanding the mechanisms that govern the fatigue behaviour of such cellular structures. It was first decided to focus on their unitary element, i.e. a single strut. Single struts samples were manufactured by Electron Beam Melting and then characterized in as-built conditions using different experimental techniques (X-ray tomography, optical and electron microscopy, etc.). Their static and cyclic tensile properties were then evaluated. The rough surface and in particular notch-like defects were found to be responsible for the knockdown of the mechanical properties. Regarding the fatigue resistance, their detrimental impact was predicted using Kitagawa diagrams. It also enabled to explain the impact of the build orientation. Different post-treatments were used in order to improve these mechanical properties. Chemical etching and ultrasonic shot peening (USP) significantly reduced the severity of surface defects of as-built thin struts and thus increased their mechanical properties. After USP, the fatigue properties of machined samples were almost matched. Hot Isostatic Pressing lead to the closure of all internal defects and to the coarsening of the microstructure. When combined with one of the surface treatments, the fatigue properties were further improved. Finally, a method enabling to systematically and automatically extract from the surface the most critical defects and quantitatively analyze their influence on fatigue life was proposed and discussed. It was successfully applied to chemical etched samples but improvements are mandatory for other surface conditions.

Fatigue of Ti-6Al-4V Thin Parts Made by Electron Beam Melting

Fatigue of Ti-6Al-4V Thin Parts Made by Electron Beam Melting PDF Author: Théo Persenot
Publisher:
ISBN:
Category :
Languages : en
Pages : 191

Get Book Here

Book Description
Nowadays, reducing the energy consumption is crucial for most of the industries. For transportation industries, it can be achieved through weight reduction. In this context, cellular structures turn out to be one of the most efficient solution. Thanks to the development of additive manufacturing, producing such complex geometries is no longer an issue. However, their use will remain limited as long as their fatigue performances are not known. This PhD work aimed at understanding the mechanisms that govern the fatigue behaviour of such cellular structures. It was first decided to focus on their unitary element, i.e. a single strut. Single struts samples were manufactured by Electron Beam Melting and then characterized in as-built conditions using different experimental techniques (X-ray tomography, optical and electron microscopy, etc.). Their static and cyclic tensile properties were then evaluated. The rough surface and in particular notch-like defects were found to be responsible for the knockdown of the mechanical properties. Regarding the fatigue resistance, their detrimental impact was predicted using Kitagawa diagrams. It also enabled to explain the impact of the build orientation. Different post-treatments were used in order to improve these mechanical properties. Chemical etching and ultrasonic shot peening (USP) significantly reduced the severity of surface defects of as-built thin struts and thus increased their mechanical properties. After USP, the fatigue properties of machined samples were almost matched. Hot Isostatic Pressing lead to the closure of all internal defects and to the coarsening of the microstructure. When combined with one of the surface treatments, the fatigue properties were further improved. Finally, a method enabling to systematically and automatically extract from the surface the most critical defects and quantitatively analyze their influence on fatigue life was proposed and discussed. It was successfully applied to chemical etched samples but improvements are mandatory for other surface conditions.

Metal Fatigue: Effects of Small Defects and Nonmetallic Inclusions

Metal Fatigue: Effects of Small Defects and Nonmetallic Inclusions PDF Author: Yukitaka Murakami
Publisher: Elsevier
ISBN: 0080496563
Category : Technology & Engineering
Languages : en
Pages : 384

Get Book Here

Book Description
Metal fatigue is an essential consideration for engineers and researchers who are looking at factors that cause metals to fail through stress, corrosion, etc. This is an English translation of a book originally published in Japan in 1993, with an additional two chapters on the fatigue failure of steels and the effect of surface roughness on fatigue strength. The methodology is based on important and reliable results and may be usefully applied to other fatigue problems not directly treated in this book.

Titanium in Medical and Dental Applications

Titanium in Medical and Dental Applications PDF Author: Francis Froes
Publisher: Woodhead Publishing
ISBN: 0128124571
Category : Technology & Engineering
Languages : en
Pages : 656

Get Book Here

Book Description
Titanium in Medical and Dental Applications is an essential reference book for those involved in biomedical materials and advanced metals. Written by well-known experts in the field, it covers a broad array of titanium uses, including implants, instruments, devices, the manufacturing processes used to create them, their properties, corrosion resistance and various fabrication approaches. Biomedical titanium materials are a critically important part of biomaterials, especially in cases where non-metallic biomedical materials are not suited to applications, such as the case of load-bearing implants. The book also covers the use of titanium for implants in the medical and dental fields and reviews the use of titanium for medical instruments and devices. - Provides an understanding of the essential and broad applications of Titanium in both the medical and dental industries - Discusses the pathways to manufacturing titanium into critical biomedical and dental devices - Includes insights into further applications within the industry

Electron Beam Melting of Metastable Austenitic Stainless Steel

Electron Beam Melting of Metastable Austenitic Stainless Steel PDF Author: Johannes Günther
Publisher: BoD – Books on Demand
ISBN: 3737608482
Category : Technology & Engineering
Languages : en
Pages : 170

Get Book Here

Book Description
The primary focus of this work is the processing – microstructure – property correlation of EBM manufactured high-alloyed austenitic CrMnNi stainless steel. Independent of the applied process parameters, to this point this alloy exhibits a fine-grained and weak textured microstructure in the as-built state upon EBM processing. As detailed in the literature review, this is opposite to numerous alloys like the benchmark AISI 316L stainless steel, which are commonly characterized by epitaxial growth of columnar grains elongated parallel to building direction. A theory for this unusual observation is presented based on a grain refinement due the process-inherent cyclic heat-treatment, i.e. repetitive reheating and partial melting of the consolidated material due to the energy input during melting of subsequent layers and resulting solid-liquid as well as solid-solid (ferritic bcc to austenitic fcc phase and vice versa) phase transformations. A calculation of the phase diagram, differential thermal II Abstract analysis and the investigation of the uppermost layers of bulky and thin-walled EBM processed structures are conducted to support this assumption. Moreover, the CrMnNi stainless steel specimens are characterized by an outstanding damage tolerance, which is demonstrated by tensile testing and examination of the fracture surfaces revealing large lack-of-fusion defects due to unsuitable process parameters. Combined EBSD and X-ray diffraction analysis attribute the high damage tolerance to a pronounced strain hardening and mitigation of the effect of defects due to the transformation-induced plasticity (TRIP) effect. The deformation-induced martensitic transformation and associated strain hardening has also been correlated to a considerable low-cycle fatigue performance even under the presence of large inhomogeneities. The chemical composition of the alloy upon EBM processing is strongly dependent on the process parameters, i.e. it is demonstrated that the evaporation rate of Mn varies with the scan strategy and volumetric energy density. This phenomenon is utilized for the fabrication of homogeneous specimens with different Mn concentrations and resulting mechanical properties.These findings are subsequently employed for a prove-of-concept of the possibility to produce functionally graded material by a spatial adjustment of the scan strategy throughout the layer-wise built-up of objects. This is a novel approach for the synthetization of functionally graded materials based on the processing of one homogenous precursor powder feedstock. In summary, the particular CrMnNi stainless steel is introduced as a novel alloy design for AM because it addresses current material-related issues inherent in layer-wise technologies and potentially further contributes to the exploitation of the full potential of AM.

Metal Foams: A Design Guide

Metal Foams: A Design Guide PDF Author: Michael F. Ashby
Publisher: Elsevier
ISBN: 0080511465
Category : Technology & Engineering
Languages : en
Pages : 267

Get Book Here

Book Description
Metal foams are at the forefront of technological development for the automotive, aerospace, and other weight-dependent industries. They are formed by various methods, but the key facet of their manufacture is the inclusion of air or other gaseous pockets in the metal structure. The fact that gas pockets are present in their structure provides an obvious weight advantage over traditionally cast or machined solid metal components. The unique structure of metal foams also opens up more opportunities to improve on more complex methods of producing parts with space inclusions such as sand-casting. This guide provides information on the advantages metal foams possess, and the applications for which they may prove suitable. - Offers a concise description of metal foams, their manufacture, and their advantages in industry - Provides engineers with answers to pertinent questions surrounding metal foams - Satisfies a major need in the market for information on the properties, performance, and applications of these materials

Titanium

Titanium PDF Author: Matthew J. Donachie
Publisher: ASM International
ISBN: 161503062X
Category : Technology & Engineering
Languages : en
Pages : 381

Get Book Here

Book Description
Designed to support the need of engineering, management, and other professionals for information on titanium by providing an overview of the major topics, this book provides a concise summary of the most useful information required to understand titanium and its alloys. The author provides a review of the significant features of the metallurgy and application of titanium and its alloys. All technical aspects of the use of titanium are covered, with sufficient metals property data for most users. Because of its unique density, corrosion resistance, and relative strength advantages over competing materials such as aluminum, steels, and superalloys, titanium has found a niche in many industries. Much of this use has occurred through military research, and subsequent applications in aircraft, of gas turbine engines, although more recent use features replacement joints, golf clubs, and bicycles.Contents include: A primer on titanium and its alloys, Introduction to selection of titanium alloys, Understanding titanium's metallurgy and mill products, Forging and forming, Castings, Powder metallurgy, Heat treating, Joining technology and practice, Machining, Cleaning and finishing, Structure/processing/property relationships, Corrosion resistance, Advanced alloys and future directions, Appendices: Summary table of titanium alloys, Titanium alloy datasheets, Cross-reference to titanium alloys, Listing of selected specification and standardization organizations, Selected manufacturers, suppliers, services, Corrosion data, Machining data.

Additive Manufacturing of Titanium Alloys

Additive Manufacturing of Titanium Alloys PDF Author: Bhaskar Dutta
Publisher: Butterworth-Heinemann
ISBN: 0128047836
Category : Technology & Engineering
Languages : en
Pages : 96

Get Book Here

Book Description
Additive Manufacturing of Titanium Alloys: State of the Art, Challenges and Opportunities provides alternative methods to the conventional approach for the fabrication of the majority of titanium components produced via the cast and wrought technique, a process which involves a considerable amount of expensive machining. In contrast, the Additive Manufacturing (AM) approach allows very close to final part configuration to be directly fabricated minimizing machining cost, while achieving mechanical properties at least at cast and wrought levels. In addition, the book offers the benefit of significant savings through better material utilization for parts with high buy-to-fly ratios (ratio of initial stock mass to final part mass before and after manufacturing). As titanium additive manufacturing has attracted considerable attention from both academicians and technologists, and has already led to many applications in aerospace and terrestrial systems, as well as in the medical industry, this book explores the unique shape making capabilities and attractive mechanical properties which make titanium an ideal material for the additive manufacturing industry. - Includes coverage of the fundamentals of microstructural evolution in titanium alloys - Introduces readers to the various Additive Manufacturing Technologies, such as Powder Bed Fusion (PBF) and Directed Energy Deposition (DED) - Looks at the future of Titanium Additive Manufacturing - Provides a complete review of the science, technology, and applications of Titanium Additive Manufacturing (AM)

Quality Analysis of Additively Manufactured Metals

Quality Analysis of Additively Manufactured Metals PDF Author: Javad Kadkhodapour
Publisher: Elsevier
ISBN: 0323886493
Category : Technology & Engineering
Languages : en
Pages : 858

Get Book Here

Book Description
Quality Analysis of Additively Manufactured Metals: Simulation Approaches, Processes, and Microstructure Properties provides readers with a firm understanding of the failure and fatigue processes of additively manufactured metals. With a focus on computational methods, the book analyzes the process-microstructure-property relationship of these metals and how it affects their quality while also providing numerical, analytical, and experimental data for material design and investigation optimization. It outlines basic additive manufacturing processes for metals, strategies for modeling the microstructural features of metals and how these features differ based on the manufacturing process, and more.Improvement of additively manufactured metals through predictive simulation methods and microdamage and micro-failure in quasi-static and cyclic loading scenarios are covered, as are topology optimization methods and residual stress analysis techniques. The book concludes with a section featuring case studies looking at additively manufactured metals in automotive, biomedical and aerospace settings. - Provides insights and outlines techniques for analyzing why additively manufactured metals fail and strategies for avoiding those failures - Defines key terms and concepts related to the failure analysis, quality assurance and optimization processes of additively manufactured metals - Includes simulation results, experimental data and case studies

Residual Stress

Residual Stress PDF Author: Ismail C. Noyan
Publisher: Springer
ISBN: 1461395704
Category : Technology & Engineering
Languages : en
Pages : 286

Get Book Here

Book Description


Additive Manufacturing of Metal Alloys 2

Additive Manufacturing of Metal Alloys 2 PDF Author: Patrice Peyre
Publisher: John Wiley & Sons
ISBN: 1789450551
Category : Technology & Engineering
Languages : en
Pages : 292

Get Book Here

Book Description