Download or read book Metallurgical and Mechanical Property Characterization of Additively Manufactured 304L Stainless Steel written by Davis M. Wilson and published by . This book was released on 2019 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book EXPERIMENTAL CHARACTERIZATION AND MODELING OF MULTIAXIAL PLASTICITY BEHAVIOR OF 304L AUSTENITIC STAINLESS STEEL 304L PRODUCED BY ADDITIVE MANUFACTURING written by Zhuqing Wang and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In additive manufacturing of metallic alloys, near-net shape 3D components are built in a layer-by-layer fashion. Austenitic stainless steels have high strength and ductility, as they tend to undergo a strain-induced martensitic phase transformation with plastic deformation. The thesis focuses on quantifying process-microstructure-multiaxial mechanical property relationships in additively manufactured 304L austenitic stainless steel (SS304L) and developing a physically-based plasticity model for this material that relates microstructural phase transformation to macroscopic mechanical properties. The effect of processing parameters on microstructure and mechanical properties was studied using pure SS304L walls. A grain growth model was used to describe austenite grain size as a function of processing parameters and location. A Hall-Petch relationship was used to explain the effect of austenite grain size and morphology on yield strength. The effects of chemistry, stress state, and texture on martensitic phase transformation were investigated using walls made using a mixture of SS304L powder and iron powder. As the concentration of elements that increase the stacking fault energy of austenite decreased, the austenite stability decreased, and the propensity for martensitic transformation increased. Multiaxial mechanical tests, including uniaxial tension, uniaxial compression, pure shear, and combined tension and shear, were performed on the material. As the primary texture resulted in a higher driving force for martensitic transformation under uniaxial compression than uniaxial tension, the rate of phase transformation was higher under uniaxial compression, which contradicted the trend in texture-free materials. A macroscopic plasticity model is proposed to describe the multiaxial plasticity behavior for the material. This model makes use of a chemistry-, stress state-, and texture-dependent martensitic transformation kinetics equation to incorporate the effect of martensitic transformation on mechanical properties. The plasticity model was implemented into a finite element code, and calibrated and validated using experimental data. The good agreement between simulation and experimental results under the stress states studied indicates the model is able to describe and predict the multiaxial mechanical behavior of additively manufactured SS304L. The results in this thesis work enable the use of additively manufactured stainless steels in structural applications, as it provides quantitative links among processing, structure, and mechanical behavior.

Download or read book Characterization of 304L Stainless Steel by Means of Minimum Input Energy on the Selective Laser Melting Platform written by Ben Brown and published by . This book was released on 2014 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Developing parameter sets for new materials on the Selective Laser Melting (SLM) platform has traditionally been done through the use of single line processing windows and a basic design of experiments (DOE) which would include varying machine parameters to maximize density. This study expands the traditional method by determining the main effects statistically for density, allowing for a more in depth analysis wherein the experimental results are statistically correlated to the variable machine parameters used. With this analysis, parameter optimization with respect to achieving near full density, while also considering build rates, can be performed. New parameters for 304L stainless steel were developed using this method on a Renishaw AM250. Single line processing windows were used to determine bounds on machine parameters. Utilizing this information, a DOE was implemented in which density samples were fabricated and the statistical main effects on density were derived. Several methods for density determination were also investigated as part of this study. In order to quantify machine parameters, a novel energy density term was formulated. Optimal parameter sets were found and energy density was reduced to increase build rate. Sensitivity of mechanical properties to the reduction was shown to be minimal over the range tested. Finally, the effect of decreased energy density on microstructure, part density, mechanical properties, and orientation sensitivity were then measured"--Abstract, page iii.

Download or read book L2 Milestone 5433 written by and published by . This book was released on 2016 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: For additive manufacturing (AM) of metallic materials, the certification and qualification paradigm needs to evolve as there currently exists no broadly accepted ?ASTM- or DIN-type? additive manufacturing certified process or AM-material produced specifications. Accordingly, design, manufacture, and thereafter implementation and insertion of AM materials to meet engineering applications requires detailed quantification of the constitutive (strength and damage) properties of these evolving materials, across the spectrum of metallic AM methods, in comparison/contrast to conventionally-manufactured metals and alloys. This report summarizes the 316L SS research results and presents initial results of the follow-on study of 304L SS. For the AM-316L SS investigation, cylindrical samples of 316L SS were produced using a LENS MR-7 laser additive manufacturing system from Optomec (Albuquerque, NM) equipped with a 1kW Yb-fiber laser. The microstructure of the AM-316L SS was characterized in both the ?as-built? Additively Manufactured state and following a heat-treatment designed to obtain full recrystallization to facilitate comparison with annealed wrought 316L SS. The dynamic shock-loading-induced damage evolution and failure response of all three 316L SS materials was quantified using flyer-plate impact driven spallation experiments at peak stresses of 4.5 and 6.35 GPa. The results of these studies are reported in detail in the first section of the report. Publication of the 316L SS results in an archival journal is planned. Following on from the 316L SS completed work, initial results on a study of AM 304L SS are in progress and presented herein. Preliminary results on the structure/dynamic spallation property behavior of AM-304L SS fabricated using both the directed-energy LENS and an EOS powder-bed AM techniques in comparison to wrought 304L SS is detailed in this Level 2 Milestone report.

Download or read book Manufacturing and Application of Stainless Steels written by Andrea Di Schino and published by MDPI. This book was released on 2020-04-15 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stainless steels represent a quite interesting material family, both from a scientific and commercial point of view, following to their excellent combination in terms of strength and ductility together with corrosion resistance. Thanks to such properties, stainless steels have been indispensable for the technological progress during the last century and their annual consumption increased faster than other materials. They find application in all these fields requiring good corrosion resistance together with ability to be worked into complex geometries. Despite to their diffusion as a consolidated materials, many research fields are active regarding the possibility to increase stainless steels mechanical properties and corrosion resistance by grain refinement or by alloying by interstitial elements. At the same time innovations are coming from the manufacturing process of such a family of materials, also including the possibility to manufacture them starting from metals powder for 3D printing. The Special Issue scope embraces interdisciplinary work covering physical metallurgy and processes, reporting about experimental and theoretical progress concerning microstructural evolution during processing, microstructure-properties relations, applications including automotive, energy and structural.

Download or read book Properties of austenitic stainless steels and their weld metals influence of slight chemistry variations written by C. R. Brinkman and published by ASTM International. This book was released on 1979 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metal Additive Manufacturing written by Dyuti Sarker and published by John Wiley & Sons. This book was released on 2021-10-26 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt: METAL ADDITIVE MANUFACTURING A comprehensive review of additive manufacturing processes for metallic structures Additive Manufacturing (AM)—also commonly referred to as 3D printing—builds three-dimensional objects by adding materials layer by layer. Recent years have seen unprecedented investment in additive manufacturing research and development by governments and corporations worldwide. This technology has the potential to replace many conventional manufacturing processes, enable the development of new industry practices, and transform the entire manufacturing enterprise. Metal Additive Manufacturing provides an up-to-date review of all essential physics of metal additive manufacturing techniques with emphasis on both laser-based and non-laser-based additive manufacturing processes. This comprehensive volume covers fundamental processes and equipment, governing physics and modelling, design and topology optimization, and more. The text adresses introductory, intermediate, and advanced topics ranging from basic additive manufacturing process classification to practical and material design aspects of additive manufacturability. Written by a panel of expert authors in the field, this authoritative resource: Provides a thorough analysis of AM processes and their theoretical foundations Explains the classification, advantages, and applications of AM processes Describes the equipment required for different AM processes for metallic structures, including laser technologies, positioning devices, feeder and spreader mechanisms, and CAD software Discusses the opportunities, challenges, and current and emerging trends within the field Covers practical considerations, including design for AM, safety, quality assurance, automation, and real-time control of AM processes Includes illustrative cases studies and numerous figures and tables Featuring material drawn from the lead author’s research and professional experience on laser additive manufacturing, Metal Additive Manufacturing is an important source for manufacturing professionals, research and development engineers in the additive industry, and students and researchers involved in mechanical, mechatronics, automatic control, and materials engineering and science.

Download or read book Friction Surfacing of 304L Austenitic Stainless Steels written by Hemant Agiwal and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Friction surfacing is a solid-state deposition process that provides microstructural and mechanical property benefits over fusion-based deposition methods as a result of the lower heat input and hot working. This study investigates friction surfacing for producing stainless steel 304L coatings on a substrate of the same material. The aims of this investigation include evaluation of the process feasibility, development of a fundamental understanding of the process physics, implementation for additive manufacturing, and application as a surface crack repair technology. Friction surfacing was performed on CNC machine tools in position control mode while observing the process forces on the back side of the deposit. During friction surfacing, the consumable rod's diameter, rotational speed, traversing feed rate, and axial feed rate were varied. Significant literature has been well-published on the impact of the traverse feed rate, axial feed rate, and spindle speed on deposition morphology and the performance of the process. However, a combined impact of the spindle speed and consumable rod diameter is missing. Through an extensive process parameter map and regression analyses, appropriate traverse and axial feed rates were found to be used across a range of spindle speeds and consumable rod diameters throughout the study. The influence of spindle speed and consumable rod diameter was studied during friction surfacing of 304L stainless steel consumable rod over the substrate of the same material. Friction surfacing was performed using a consumable rod with diameters of 4.76 mm, 9.52 mm, and 12.7 mm, while using spindle speeds from 1,500-20,000 RPM, keeping the other parameters constant. The impact of spindle speed on deposition morphology, including the radius of contact, was studied. The radius of contact was calculated empirically and was found to be inversely proportional to the tangential velocity of the rod. In this study, a new dimensionless number [sigma] is introduced, which is the ratio of the thermal heat generated by plastic work during friction surfacing and the thermal diffusivity of the material. The heat flux and axial pressures were calculated analytically and were found to be strongly correlated with [sigma]. The bonding characteristics were analyzed by performing peel-off and tensile tests on the coatings, and it was found that the bonding characteristics improved by increasing [sigma] during friction surfacing. This study provides analytical relations that can be used to select the right combination of consumable rod diameter and spindle speed for a given application during friction surfacing. The study examines microstructure and corrosion properties for friction surfaced 304L stainless steel consumable rods on 304L stainless steel substrates. Microstructural characterization revealed fine-grained microstructure with distributed strain-induced martensite and high residual compressive stresses. Corrosion studies of friction surfaced specimens were carried out by exposure to FeCl3 and MgCl2 solutions per ASTM G48 and ASTM G36 standards, respectively. The corrosion tests showed friction surfacing led to shallower and smaller pits than the uncoated substrate. However, the pit number density was higher in the friction surfaced specimens. The microstructural transformations during friction surfacing are beneficial to mitigating pitting corrosion and potentially chloride-induced stress corrosion cracking (CISCC). Friction surfacing was investigated as a method for sealing 50 [mu]m wide thru-cracks in 3-mm-thick 304L stainless steel (304L) plate. Friction surfacing was performed using two sizes of 304L consumable rod, with diameters of 9.52 mm and 12.7 mm, on two substrate conditions (clean and oxidized). Friction surfacing was able to deposit a 600 [mu]m coating, and repair cracks to a depth of 100 [mu]m - 200 [mu]m below the original surface when using the 12.7-mm-diameter consumable rod for both substrate conditions. Helium leak rates of 10-10 atm-cc/sec were achieved using tests designated as leak-tight by the ANSI N14.5 standard. Optical and scanning electron microscopy were used to investigate the coating microstructure and bond interfaces. It was found the 12.7mm-diameter rod performed better with disruption of the oxide layer on the oxidized substrate and providing a more homogenous coating. The mechanical properties of the coated samples were evaluated by performing micro-indentation, tensile, bending, and adhesion tests. Higher hardness in the coatings was observed due to the fine equiaxed grains resulting from dynamic recrystallization. Complete consolidation of plastically deformed material on the substrate and a strong diffusion bond across the interface was observed. This was reflected in the tensile and bending properties of the friction surfaced coatings being comparable to those of uncoated specimens. No delamination of the friction surfaced coating was observed during adhesion testing. The results demonstrate that friction surfacing is a viable option for repairing cracks in stainless steel. The crack repair was also performed at 20,000 RPM using a 4.76 mm consumable rod. Leak-tight crack repair was achieved while remaining the process forces below 500N. Thus, the applicability of the process as a low-force solid-state repair technology was demonstrated. Friction surfacing was next studied as a solid state metal additive process by depositing a succession of coating layers. The objective of this work is to study friction surfacing process variability when depositing multilayered coatings. This is motivated by the need to maintain deposition quality when depositing multiple friction surfacing layers, whether for repair, remanufacturing, or new part creation using this solid-state metal additive manufacturing process. In this study, 10-mm-diameter 304L stainless steel rods were used to create up to five layers of 40-mm-long coatings on 304L substrates using a constant set of processing parameters. In-process measurement of forces (X, Y, Z), flash temperature, flash geometry, layer temperature, and post-process measurement of layer geometry, microhardness, and microstructure are used to characterize changes in the friction surfacing process as more layers are deposited. It was observed that with increasing layers: layer thickness and deposition efficiency decrease; offsetting of the deposition towards the retreating side, and temperature in the deposited layer increase; and flash temperature does not change. Metallurgical analyses of friction surfaced cross-sections revealed fine grain refinement and transformation of base austenite to strain-induced martensite. It is concluded that the process parameters need to be adjusted even after the second or third layer is deposited, corrections to the tool path are required after a couple of layers, and the measured process forces, as well as deposited layer temperature, may be useful to monitor and control the process and its instabilities. Through this study, multiple facets of the friction surfacing process for austenitic stainless steels were studied. The results from the study demonstrate friction surfacing as a viable technology to produce solid-state coatings with superior mechanical, microstructural, and corrosion properties for surface crack repair applications.

Download or read book Laser Additive Manufacturing of Metallic Materials and Components written by Dongdong Gu and published by Elsevier. This book was released on 2022-12-07 with total page 824 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser Additive Manufacturing of Metallic Materials and Components discusses the current state and future development of laser additive manufacturing technologies, detailing material, structure, process and performance. The book explores the fundamental scientific theories and technical principles behind the elements of laser additive manufacturing, touching upon scientific and technological challenges faced by laser additive manufacturing technology. This book is suitable for those who want to further "understand and "master laser additive manufacturing technology and will expose readers to innovative industrial applications that meet significant demand from aeronautical and astronautical high-end modern industries for low-cost, short-cycle and net-shape manufacturing of structure-function integrated metallic components. With the increasing use of industrial applications, additive manufacturing processes are deepening, with technology continuing to evolve. As new scientific and technological challenges emerge, there is a need for an interdisciplinary and comprehensive discussion of material preparation and forming, structure design and optimization, laser process and its control, microstructure and performance characterization, and innovative industrial applications, hence this book covers these important aspects. - Highlights an integration of material, structure, process and performance for laser additive manufacturing of metallic components to reflect the interdisciplinary nature of this technology - Covers cross-scale structure and performance coordination mechanisms, including micro-scale material microstructure control, meso-scale interaction between laser beam and particle matter, and macro-scale precise forming of components and performance control - Explores fundamental scientific theories and technical principles behind laser additive manufacturing processes - Provides innovation elements and strategies for the future sustainable development of additive manufacturing technologies in terms of multi-materials design, novel bio-inspired structure design, tailored printing process with meso-scale monitoring, and high-performance and functionality of printed components

Download or read book Journal written by American Veterinary Medical Association and published by . This book was released on 2015-09-26 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.

Download or read book Fatigue and Fracture Behavior of Additively Manufactured Austenitic Stainless Steel written by Chris San Marchi and published by . This book was released on 2020 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Additive manufacturing (AM) includes a diverse suite of innovative manufacturing processes for producing near-net shape components, typically from powder or wire feedstock. Reported mechanical properties of AM materials vary significantly depending on the details of the manufacturing process and the characteristics of the processing defects (namely, lack of fusion defects). However, an excellent combination of strength, ductility, and fracture resistance can be achieved in AM-type 304L and 316L austenitic stainless steels by minimizing processing defects. It is important to recognize that localized solidification processing during AM produces microstructures more analogous to weld microstructures than wrought microstructures. Consequently, the mechanical behavior of AM austenitic stainless steels in harsh environments can diverge from the performance of wrought materials. This report provides an overview of the fracture and fatigue response of type 304L materials from both directed energy deposition and powder bed fusion techniques. In particular, the mechanical performance of these materials is considered for high-pressure hydrogen applications by evaluating fatigue and fracture resistance after thermally precharging test specimens in high-pressure gaseous hydrogen. The mechanical behaviors are considered with respect to previous reports on hydrogen-assisted fracture of austenitic stainless steel welds and the unique characteristics of the AM microstructures. Fatigue crack growth can be relatively insensitive to processing defects, displaying similar behavior as wrought materials. In contrast, fracture resistance of dense AM austenitic stainless steel is more consistent with weld metal than with compositionally similar wrought materials. Hydrogen effects in the AM materials generally are more severe than in wrought materials but are comparable to measurements on welded austenitic stainless steels in hydrogen environments. Although hydrogen-assisted fracture manifests differently in welded and AM austenitic stainless steel, the fracture process appears to have a common origin in the compositional microsegregation intrinsic to solidification processes.

Download or read book Additive Manufacturing Second Edition written by Amit Bandyopadhyay and published by CRC Press. This book was released on 2019-10-16 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Characterization of Functionally Graded Materials Based on Inconel 718 and Stainless Steel 316L Manufactured by DED Process written by Jan Dzugan and published by . This book was released on 2020 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Additive manufacturing (AM) processes are being widely investigated and gradually applied for engineering applications. Presently, the main focus is on single material systems deposition, where there are still many issues with process stability and repeatability. However, a further huge leap in the field of AM process development will be the design of multiple material heterogeneous components. The current study presents investigation of an experimental build consisting of multiple layers of austenitic stainless steel 316L and Inconel 718, which was created by a powder blow direct energy deposition system allowing simultaneous multiple materials' deposition. Results report details of the microstructure investigation using optical metallography and scanning electron microscopy (SEM) analysis focusing on transition regions between the materials, where a significant difference was found in transition steel to Inconel and Inconel to steel. Hardness profile across deposited layers is established. Mechanical property assessment of the materials within the single material layers over the materials' transition in the horizontal direction as well as across multimaterial layers in the building direction was carried out with the use of minitensile specimens. Results obtained in this study demonstrate the importance of the order of deposited materials and the effect on their mechanical properties.

Download or read book Mechanical Behavior of Additively Manufactured 304L Stainless Steel written by and published by . This book was released on 2015 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Welding of Maraging Steels written by F. H. Lang and published by . This book was released on 1971 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser Additive Manufacturing written by Milan Brandt and published by Woodhead Publishing. This book was released on 2016-09-01 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser Additive Manufacturing: Materials, Design, Technologies, and Applications provides the latest information on this highly efficient method of layer-based manufacturing using metals, plastics, or composite materials. The technology is particularly suitable for the production of complex components with high precision for a range of industries, including aerospace, automotive, and medical engineering. This book provides a comprehensive review of the technology and its range of applications. Part One looks at materials suitable for laser AM processes, with Part Two discussing design strategies for AM. Parts Three and Four review the most widely-used AM technique, powder bed fusion (PBF) and discuss other AM techniques, such as directed energy deposition, sheet lamination, jetting techniques, extrusion techniques, and vat photopolymerization. The final section explores the range of applications of laser AM. Provides a comprehensive one-volume overview of advances in laser additive manufacturing Presents detailed coverage of the latest techniques used for laser additive manufacturing Reviews both established and emerging areas of application

Download or read book Modeling the Mechanical Behavior of Additively Manufactured 304L Stainless Steel written by and published by . This book was released on 2015 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: