Download or read book Microstructure and the Characterisation of Mechanical Properties of Wire Arc Additively Manufactured Nickel base Superalloys written by Cui Seow and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alloy Design and Characterization of Strengthened Nickel based Superalloys for Additive Manufacturing written by Jinghao Xu and published by Linköping University Electronic Press. This book was released on 2021-01-28 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nickel-based superalloys, an alloy system bases on nickel as the matrix element with the addition of up to 10 more alloying elements including chromium, aluminum, cobalt, tungsten, molybdenum, titanium, and so on. Through the development and improvement of nickel-based superalloys in the past century, they are well proved to show excellent performance at the elevated service temperature. Owing to the combination of extraordinary high-temperature mechanical properties, such as monotonic and cyclic deformation resistance, fatigue crack propagation resistance; and high-temperature chemical properties, such as corrosion and oxidation resistance, phase stability, nickel-based superalloys are widely used in the critical hot-section components in aerospace and energy generation industries. The success of nickel-based superalloy systems attributes to both the well-tailored microstructures with the assistance of carefully doped alloying elements, and the intently developed manufacturing processes. The microstructure of the modern nickel-based superalloys consists of a two-phase configuration: the intermetallic precipitates (Ni,Co)3(Al,Ti,Ta) known as γ′ phase dispersed into the austenite γ matrix, which is firstly introduced in the 1940s. The recently developed additive manufacturing (AM) techniques, acting as the disruptive manufacturing process, offers a new avenue for producing the nickel-based superalloy components with complicated geometries. However, γ′ strengthened nickel-based superalloys always suffer from the micro-cracking during the AM process, which is barely eliminated by the process optimization. On this basis, the new compositions of γ′ strengthened nickel-based superalloy adapted to the AM process are of great interest and significance. This study sought to design novel γ′ strengthened nickel-based superalloys readily for AM process with limited cracking susceptibility, based on the understanding of the cracking mechanisms. A two-parameter model is developed to predict the additive manufacturability for any given composition of a nickel-based superalloy. One materials index is derived from the comparison of the deformation-resistant capacity between dendritic and interdendritic regions, while another index is derived from the difference of heat resistant capacity of these two spaces. By plotting the additive manufacturability diagram, the superalloys family can be categorized into the easy-to-weld, fairly-weldable, and non-weldable regime with the good agreement of the existed knowledge. To design a novel superalloy, a Cr-Co-Mo-W-Al-Ti-Ta-Nb-Fe-Ni alloy family is proposed containing 921,600 composition recipes in total. Through the examination of additive manufacturability, undesired phase formation propensity, and the precipitation fraction, one composition of superalloy, MAD542, out of the 921,600 candidates is selected. Validation of additive manufacturability of MAD542 is carried out by laser powder bed fusion (LPBF). By optimizing the LPBF process parameters, the crack-free MAD542 part is achieved. In addition, the MAD542 superalloy shows great resistance to the post-processing treatment-induced cracking. During the post-processing treatment, extensive annealing twins are promoted to achieve the recrystallization microstructure, ensuring the rapid reduction of stored energy. After ageing treatment, up to 60-65% volume fraction of γ′ precipitates are developed, indicating the huge potential of γ′ formation. Examined by the high-temperature slow strain rate tensile and constant loading creep testing, the MAD542 superalloy shows superior strength than the LPBF processed and hot isostatic pressed plus heat-treated IN738LC superalloy. While the low ductility of MAD542 is existed, which is expected to be improved by modifying the post-processing treatment scenarios and by the adjusting building direction in the following stages of the Ph.D. research. MAD542 superalloy so far shows both good additive manufacturability and mechanical potentials. Additionally, the results in this study will contribute to a novel paradigm for alloy design and encourage more γ′-strengthened nickel-based superalloys tailored for AM processes in the future.
Download or read book Welding Metallurgy and Weldability of Nickel Base Alloys written by John C. Lippold and published by John Wiley & Sons. This book was released on 2011-09-20 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: The most up-to-date coverage of welding metallurgy aspects and weldability issues associated with Ni-base alloys Welding Metallurgy and Weldability of Nickel-Base Alloys describes the fundamental metallurgical principles that control the microstructure and properties of welded Ni-base alloys. It serves as a practical how-to guide that enables engineers to select the proper alloys, filler metals, heat treatments, and welding conditions to ensure that failures are avoided during fabrication and service. Chapter coverage includes: Alloying additions, phase diagrams, and phase stability Solid-solution strengthened Ni-base alloys Precipitation strengthened Ni-base alloys Oxide dispersion strengthened alloys and nickel aluminides Repair welding of Ni-base alloys Dissimilar welding Weldability testing High-chromium alloys used in nuclear power applications With its excellent balance between the fundamentals and practical problem solving, the book serves as an ideal reference for scientists, engineers, and technicians, as well as a textbook for undergraduate and graduate courses in welding metallurgy.
Download or read book Additively Manufactured Inconel 718 written by Dunyong Deng and published by Linköping University Electronic Press. This book was released on 2018-01-24 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: Additive manufacturing (AM), also known as 3D printing, has gained significant interest in aerospace, energy, automotive and medical industries due to its capabilities of manufacturing components that are either prohibitively costly or impossible to manufacture by conventional processes. Among the various additive manufacturing processes for metallic components, electron beam melting (EBM) and selective laser melting (SLM) are two of the most widely used powder bed based processes, and have shown great potential for manufacturing high-end critical components, such as turbine blades and customized medical implants. The futures of the EBM and SLM are doubtlessly promising, but to fully realize their potentials there are still many challenges to overcome. Inconel 718 (IN718) is a nickel-base superalloy and has impressive combination of good mechanical properties and low cost. Though IN718 is being mostly used as a turbine disk material now, the initial introduction of IN718 was to overcome the poor weldability of superalloys in 1960s, since sluggish precipitation of strengthening phases ?’/?’’ enables good resistance to strain-age cracking during welding or post weld heat treatment. Given the similarity between AM and welding processes, IN718 has been widely applied to the metallic AM field to facilitate the understandings of process-microstructure-property relationships. The work presented in this licentiate thesis aims to better understand microstructures and mechanical properties EBM and SLM IN718, which have not been systematically investigated. Microstructures of EBM and SLM IN718 have been characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM) and correlated with the process conditions. Monotonic mechanical properties (e.g., Vickers microhardness and tensile properties) have also been measured and rationalized with regards to the microstructure evolutions before and after heat treatments. For EBM IN718, the results show the microstructure is not homogeneous but dependant on the location in the components, and the anisotropic mechanical properties are probably attributed to alignment of porosities rather than texture. Post heat treatment can slightly increase the mechanical strength compared to the as-manufactured condition but does not alter the anisotropy. SLM IN718 shows significantly different microstructure and mechanical properties to EBM IN718. The as-manufactured SLM IN718 has very fine dendritic microstructure and Laves phases in the interdendrites, and is “work-hardened” by the residual strains and dislocations present in the material. Mechanical properties are different between horizontally and vertically built samples, and heat treatment can minimize this difference. Results from this licentiate thesis provide the basis for the further research on the cyclic mechanical properties of EBM and SLM IN718, which would be the focus of following phase of the Ph.D. research.
Download or read book Welding Metallurgy of Stainless Steels written by Erich Folkhard and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt: When considering the operational performance of stainless steel weldments the most important points to consider are corrosion resistance, weld metal mechanical properties and the integrity ofthe weldedjoint. Mechanical and corrosion resistance properties are greatly influenced by the metallurgical processes that occur during welding or during heat treatment of welded components. This book is aimed, there fore, at providing information on the metallurgical problems that may be encountered during stainless steel welding. In this way we aim to help overcome a certain degree of insecurity that is often encountered in welding shops engaged in the welding of stainless steels and is often the cause of welding problems which may in some instances lead to the premature failure of the welded component. The metallurgical processes that occur during the welding of stainless steel are of a highly intricate nature. The present book focuses in particular on the signif icance of constitution diagrams, on the processes occurring during the solidification of weld metal and on the recrystallization and precipitation phenomena which take place in the area of the welds. There are specific chapters covering the hot cracking resistance during welding and the practical welding of a number of different stainless steel grades. In addition, recommendations are given as to the most suitable procedures to be followed in order to obtain maximum corrosion resistance and mechanical properties from the weldments.
Download or read book Superalloys written by Matthew J. Donachie and published by ASM International. This book was released on 2002 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers virtually all technical aspects related to the selection, processing, use, and analysis of superalloys. The text of this new second edition has been completely revised and expanded with many new figures and tables added. In developing this new edition, the focus has been on providing comprehensive and practical coverage of superalloys technology. Some highlights include the most complete and up-to-date presentation available on alloy melting. Coverage of alloy selection provides many tips and guidelines that the reader can use in identifying an appropriate alloy for a specific application. The relation of properties and microstructure is covered in more detail than in previous books.
Download or read book Characterization of a Nickel base Superalloy Through Electrical Resistivity microstructure Relationships Facilitated by Small Angle Scattering written by Ricky Lee Whelchel and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nickel-base superalloys obtain high temperature mechanical properties through formation of precipitate phases formed via heat treatment. The precipitate microstructure evolves with heat treatment or thermal exposure, which can lead to degrading mechanical properties. This project focuses on the use of electrical resistivity as a non-destructive testing method to monitor the precipitate phase in Waspaloy (a polycrystalline nickel-base superalloy). The evolution of the precipitate microstructure is characterized throughout the volume of the specimens using both small angle neutron scattering (SANS) and ultra small angle X-ray scattering (USAXS) measurements. These measurements are also aided by microscopy and X-ray diffraction measurements.
Download or read book Superalloys 2020 written by Sammy Tin and published by Springer Nature. This book was released on 2020-08-28 with total page 1098 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 14th International Symposium on Superalloys (Superalloys 2020) highlights technologies for lifecycle improvement of superalloys. In addition to the traditional focus areas of alloy development, processing, mechanical behavior, coatings, and environmental effects, this volume includes contributions from academia, supply chain, and product-user members of the superalloy community that highlight technologies that contribute to improving manufacturability, affordability, life prediction, and performance of superalloys.
Download or read book Additive Manufacturing of Metals written by John O. Milewski and published by Springer. This book was released on 2017-06-28 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: This engaging volume presents the exciting new technology of additive manufacturing (AM) of metal objects for a broad audience of academic and industry researchers, manufacturing professionals, undergraduate and graduate students, hobbyists, and artists. Innovative applications ranging from rocket nozzles to custom jewelry to medical implants illustrate a new world of freedom in design and fabrication, creating objects otherwise not possible by conventional means. The author describes the various methods and advanced metals used to create high value components, enabling readers to choose which process is best for them. Of particular interest is how harnessing the power of lasers, electron beams, and electric arcs, as directed by advanced computer models, robots, and 3D printing systems, can create otherwise unattainable objects. A timeline depicting the evolution of metalworking, accelerated by the computer and information age, ties AM metal technology to the rapid evolution of global technology trends. Charts, diagrams, and illustrations complement the text to describe the diverse set of technologies brought together in the AM processing of metal. Extensive listing of terms, definitions, and acronyms provides the reader with a quick reference guide to the language of AM metal processing. The book directs the reader to a wealth of internet sites providing further reading and resources, such as vendors and service providers, to jump start those interested in taking the first steps to establishing AM metal capability on whatever scale. The appendix provides hands-on example exercises for those ready to engage in experiential self-directed learning.
Download or read book Progress in Metal Additive Manufacturing and Metallurgy written by Robert Pederson and published by MDPI. This book was released on 2020-12-03 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: The advent of additive manufacturing (AM) processes applied to the fabrication of structural components creates the need for design methodologies supporting structural optimization approaches that take into account the specific characteristics of the process. While AM processes enable unprecedented geometrical design freedom, which can result in significant reductions of component weight, on the other hand they have implications in the fatigue and fracture strength due to residual stresses and microstructural features. This is linked to stress concentration effects and anisotropy that still warrant further research. This Special Issue of Applied Sciences brings together papers investigating the features of AM processes relevant to the mechanical behavior of AM structural components, particularly, but not exclusively, from the viewpoints of fatigue and fracture behavior. Although the focus of the issue is on AM problems related to fatigue and fracture, articles dealing with other manufacturing processes with related problems are also be included.
Download or read book Superalloys 2012 written by Eric S. Huron and published by John Wiley & Sons. This book was released on 2012-10-02 with total page 952 pages. Available in PDF, EPUB and Kindle. Book excerpt: A superalloy, or high-performance alloy, is an alloy that exhibits excellent mechanical strength at high temperatures. Superalloy development has been driven primarily by the aerospace and power industries. This compilation of papers from the Twelfth International Symposium on Superalloys, held from September 9-13, 2012, offers the most recent technical information on this class of materials.
Download or read book The Microstructure of Superalloys written by Madeleine Durand-Charre and published by Routledge. This book was released on 2017-11-22 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents all the main aspects of the microstructure of nickel-base superalloys, and includes micrographs chosen from among a large range of commercial and academic alloys, from the as-cast product to in-situ components, worn from in-service use. Including more than 100 illustrations, the text explains all the transformation mechanisms involved in the origination (creation) of microstructures during solidification or heat treatments (crystallization paths, segregation, crystal orientation, precipitation, TCP, coarsening and rafting, etc.). It includes up-to-date information and data such as phase diagrams, crystallographic structures, and relationships with functional properties. Nearly 300 references provide a key to further investigation.
Download or read book Microstructure and Mechanical Properties of Nickel based Superalloy Hastelloy X Fabricated by Laser Powder Bed Fusion written by Oscar Sanchez Mata and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Additive manufacturing (AM), particularly laser powder bed fusion (LPBF) has been used to process Ni-based superalloys as an alternative to traditional manufacturing methods. However, they can be prone to cracking when fabricated through LPBF. Hastelloy X (HX) is a solid solution strengthened (SSS) alloy that although being categorized as readily weldable, suffers from cracking during LPBF. This document presents a study of crack-free LPBF HX microstructures, their behaviour after post-processing and their relationship with mechanical properties. Moreover, the application of unique microstructural features that result from LPBF processing to scale from bulk to more complex parts and tailor mechanical properties is documented. Crack-free HX fabricated through LPBF from powder having a standard chemical composition is reported. Electron backscatter diffraction (EBSD) analysis evidenced columnar grains parallel to the building direction (BD). The columnar sub-grain solidification microstructure was found to be finer than reported elsewhere. Mo-enriched carbides (~50 nm), were identified along interdendritic regions. The crack-free condition was maintained after heat treatment at 1177 °C for 1 h and its microstructure was analyzed. Dense and crack-free specimens were printed in both horizontal and vertical orientations. Samples were analyzed in as-built (AB), hot isostatic pressing treatment (HIP), and conventional heat treatment (HT) conditions. Tensile testing was done at room and elevated temperature (RT, ET = 750°C). AB samples showed columnar grains and a partial fiber texture aligned with the BD, which was reduced after HIP and HT. Mo and Cr carbides were found at RT which grew after ET. AB samples displayed high ultimate tensile strength (UTS) up to 924 ± 10 MPa, while strength values remained close to a reference HX wrought alloy after HIP and HT. Although lower ductility was observed for AB samples at ET, elongation was improved after HIP and HT. Strength and elongation comparable to that of the wrought alloy at RT can be obtained by only performing conventional HT, without the need of HIP. Dense and crack-free LPBF HX thin cylindrical struts with diameters from 0.25 to 2 mm were built. Their crystallographic texture transitioned from a 110 || BD fiber texture (2 mm), to a single crystal 110 || BD (0.25 mm). The size of cellular sub-grain microstructure increased as strut diameter decreased and was linked with an inverse trend in microhardness, which was the highest in the 2 mm strut due to a smaller cell size. Lower hardness in regions close to the strut edges was also related to a larger observed cell size. From tensile testing, elongation was measured at 35-50%. Deformation twinning and lattice rotation after testing were observed. Differences in strength between struts of different diameter were discussed. Fractography analysis confirmed the ductile fracture behavior. Finally, the unique strong crystallographic texture behaviour of LPBF HX was studied in more detail. Tensile properties at RT were investigated along the 100, 110, and 111 crystallographic orientations. Tensile behavior was highly dependent on crystallographic orientation and showed a good combination of strength and ductility when compared with other LPBF HX. EBSD analysis after fracture revealed deformation twinning in 110 and 111 samples, but not in 100. Crystallographic orientation had an impact on the effective stacking fault energies and on the critical stress for deformation twinning. The latter was near or below the yield strength (YS) value for 110 and 111, while it was above the UTS of the 100 orientation. The YS value of 111 (807 ± 28 MPa) was higher than for 100 (693 ± 8 MPa) and 110 (648 ± 13 MPa). Results suggest that deformation twinning can occur in SSS Ni-based superalloys at RT. In contrast to the 100 and 111 orientations, rotation of the lattice after deformation was found for the 110 direction"--
Download or read book Superalloys 2024 written by Jonathan Cormier and published by Springer Nature. This book was released on with total page 1121 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Additive Manufacturing of Metals The Technology Materials Design and Production written by Li Yang and published by Springer. This book was released on 2017-05-11 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a unique guide to the three-dimensional (3D) printing of metals. It covers various aspects of additive, subtractive, and joining processes used to form three-dimensional parts with applications ranging from prototyping to production. Examining a variety of manufacturing technologies and their ability to produce both prototypes and functional production-quality parts, the individual chapters address metal components and discuss some of the important research challenges associated with the use of these technologies. As well as exploring the latest technologies currently under development, the book features unique sections on electron beam melting technology, material lifting, and the importance this science has in the engineering context. Presenting unique real-life case studies from industry, this book is also the first to offer the perspective of engineers who work in the field of aerospace and transportation systems, and who design components and manufacturing networks. Written by the leading experts in this field at universities and in industry, it provides a comprehensive textbook for students and an invaluable guide for practitioners
Download or read book Some Effects of Microstructure on the Mechanical Properties of Nickel base Superalloys written by C. P. Sullivan and published by . This book was released on 1966 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transactions on Intelligent Welding Manufacturing written by Shanben Chen and published by Springer. This book was released on 2019-02-06 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary aim of this volume is to provide researchers and engineers from both academia and industry with up-to-date coverage of recent advances in the fields of robotic welding, intelligent systems and automation. It gathers selected papers from the 2018 International Conference on Robotic Welding, Intelligence and Automation (RWIA 2018), held Oct 20-22, 2018 in Guangzhou, China. The contributions reveal how intelligentized welding manufacturing (IWM) is becoming an inescapable trend, just as intelligentized robotic welding is becoming a key technology. The volume is divided into four main parts: Intelligent Techniques for Robotic Welding, Sensing in Arc Welding Processing, Modeling and Intelligent Control of Welding Processing, and Intelligent Control and its Applications in Engineering.
