Author: Andreas Nau
Publisher: kassel university press GmbH
ISBN: 3737600546
Category :
Languages : en
Pages : 223
Book Description
A Contribution to Enlarge the Application Limits of Residual Stress Analyses by the Hole-Drilling and the Ring-Core Method
Author: Andreas Nau
Publisher: kassel university press GmbH
ISBN: 3737600546
Category :
Languages : en
Pages : 223
Book Description
Publisher: kassel university press GmbH
ISBN: 3737600546
Category :
Languages : en
Pages : 223
Book Description
Residual stress analysis in polymer materials using the hole drilling method – basic principles and applications
Author: Arnaud Magnier
Publisher: kassel university press GmbH
ISBN: 3737606447
Category : Materials
Languages : en
Pages : 125
Book Description
Publisher: kassel university press GmbH
ISBN: 3737606447
Category : Materials
Languages : en
Pages : 125
Book Description
Electron Beam Melting of Metastable Austenitic Stainless Steel
Author: Johannes Günther
Publisher: BoD – Books on Demand
ISBN: 3737608482
Category : Technology & Engineering
Languages : en
Pages : 170
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.
Publisher: BoD – Books on Demand
ISBN: 3737608482
Category : Technology & Engineering
Languages : en
Pages : 170
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.
Hot work tool steel in laser powder bed fusion: from parameter optimization to quality monitoring in industrial application
Author: Liang Wu
Publisher: BoD – Books on Demand
ISBN: 3737611785
Category : Technology & Engineering
Languages : en
Pages : 202
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.
Publisher: BoD – Books on Demand
ISBN: 3737611785
Category : Technology & Engineering
Languages : en
Pages : 202
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.
Springer Handbook of Experimental Solid Mechanics
Author: William N. Sharpe, Jr.
Publisher: Springer Science & Business Media
ISBN: 0387268839
Category : Mathematics
Languages : en
Pages : 1100
Book Description
The Springer Handbook of Experimental Solid Mechanics documents both the traditional techniques as well as the new methods for experimental studies of materials, components, and structures. The emergence of new materials and new disciplines, together with the escalating use of on- and off-line computers for rapid data processing and the combined use of experimental and numerical techniques have greatly expanded the capabilities of experimental mechanics. New exciting topics are included on biological materials, MEMS and NEMS, nanoindentation, digital photomechanics, photoacoustic characterization, and atomic force microscopy in experimental solid mechanics. Presenting complete instructions to various areas of experimental solid mechanics, guidance to detailed expositions in important references, and a description of state-of-the-art applications in important technical areas, this thoroughly revised and updated edition is an excellent reference to a widespread academic, industrial, and professional engineering audience.
Publisher: Springer Science & Business Media
ISBN: 0387268839
Category : Mathematics
Languages : en
Pages : 1100
Book Description
The Springer Handbook of Experimental Solid Mechanics documents both the traditional techniques as well as the new methods for experimental studies of materials, components, and structures. The emergence of new materials and new disciplines, together with the escalating use of on- and off-line computers for rapid data processing and the combined use of experimental and numerical techniques have greatly expanded the capabilities of experimental mechanics. New exciting topics are included on biological materials, MEMS and NEMS, nanoindentation, digital photomechanics, photoacoustic characterization, and atomic force microscopy in experimental solid mechanics. Presenting complete instructions to various areas of experimental solid mechanics, guidance to detailed expositions in important references, and a description of state-of-the-art applications in important technical areas, this thoroughly revised and updated edition is an excellent reference to a widespread academic, industrial, and professional engineering audience.
Hole-Drilling Method for Measuring Residual Stresses
Author: Gary S.
Publisher: Springer Nature
ISBN: 3031797132
Category : Technology & Engineering
Languages : en
Pages : 172
Book Description
This book describes the theory and practice of the Hole-Drilling Method for measuring residual stresses in engineering components. Such measurements are important because residual stresses have a "hidden" character because they exist locked-in within a material, independent of any external load. These stresses are typically created during component manufacture, for example, during welding, casting, or forming. Because of their hidden nature, residual stresses are difficult to measure and consequently are often ignored. However, they directly add to loading stresses and can cause catastrophic failure if not properly included during engineering design. Thus, there is an urgent need to be able to identify and measure residual stresses conveniently and reliably. The Hole-Drilling Method provides an adaptable and well-proven method for measuring residual stresses in a wide range of materials and component types. It is convenient to use and gives reliable results. Because of the hidden nature of residual stresses, the measurement method must necessarily be indirect, thus, additional care and conceptual understanding are necessary to achieve successful results. This book provides a practical introduction to the Hole-Drilling Method, starting from its historical roots and going on to focus on its modern practice. The various chapters describe the nature of residual stresses, the principle of hole-drilling measurements, procedures and guidance on how to make successful measurements, and effective mathematical procedures for stress computation and analysis. The book is intended for practitioners who need to make residual stress measurements either occasionally or routinely, for practicing engineers, for researchers, and for graduate engineering and science students.
Publisher: Springer Nature
ISBN: 3031797132
Category : Technology & Engineering
Languages : en
Pages : 172
Book Description
This book describes the theory and practice of the Hole-Drilling Method for measuring residual stresses in engineering components. Such measurements are important because residual stresses have a "hidden" character because they exist locked-in within a material, independent of any external load. These stresses are typically created during component manufacture, for example, during welding, casting, or forming. Because of their hidden nature, residual stresses are difficult to measure and consequently are often ignored. However, they directly add to loading stresses and can cause catastrophic failure if not properly included during engineering design. Thus, there is an urgent need to be able to identify and measure residual stresses conveniently and reliably. The Hole-Drilling Method provides an adaptable and well-proven method for measuring residual stresses in a wide range of materials and component types. It is convenient to use and gives reliable results. Because of the hidden nature of residual stresses, the measurement method must necessarily be indirect, thus, additional care and conceptual understanding are necessary to achieve successful results. This book provides a practical introduction to the Hole-Drilling Method, starting from its historical roots and going on to focus on its modern practice. The various chapters describe the nature of residual stresses, the principle of hole-drilling measurements, procedures and guidance on how to make successful measurements, and effective mathematical procedures for stress computation and analysis. The book is intended for practitioners who need to make residual stress measurements either occasionally or routinely, for practicing engineers, for researchers, and for graduate engineering and science students.
Residual Stresses in Composite Materials
Author: Mahmood M. Shokrieh
Publisher: Woodhead Publishing
ISBN: 0857098594
Category : Technology & Engineering
Languages : en
Pages : 407
Book Description
Residual stresses are a common phenomenon in composite materials. They can either add to or significantly reduce material strength. Because of the increasing demand for high-strength, light-weight materials such as composites and their wide range of applications in the aerospace and automotive industries, in civil infrastructure and in sporting applications, it is critical that the residual stresses of composite materials are understood and measured correctly.The first part of this important book reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses. Various mathematical (analytical and numerical) methods for calculation of residual stresses in composite materials are also presented. Chapters in the first section of the book discuss the simulated hole drilling method, the slitting/crack compliance method, measuring residual stresses in homogeneous and composite glass materials using photoelastic techniques, and modeling residual stresses in composite materials. The second part of the book discusses residual stresses in polymer matrix, metal-matrix and a range of other types of composites. Moreover, the addition of nanoparticles to the matrix of polymeric composites as a new technique for reduction of residual stresses is discussed.Residual stresses in composite materials provides a comprehensive overview of this important topic, and is an invaluable reference text for both academics and professionals working in the mechanical engineering, civil engineering, aerospace, automotive, marine and sporting industries. - Reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses - Discusses residual stresses in polymer matrix, metal-matrix and other types of composite - Considers the addition of nanoparticles to the matrix of polymeric composites as a new technique for reduction of residual stresses
Publisher: Woodhead Publishing
ISBN: 0857098594
Category : Technology & Engineering
Languages : en
Pages : 407
Book Description
Residual stresses are a common phenomenon in composite materials. They can either add to or significantly reduce material strength. Because of the increasing demand for high-strength, light-weight materials such as composites and their wide range of applications in the aerospace and automotive industries, in civil infrastructure and in sporting applications, it is critical that the residual stresses of composite materials are understood and measured correctly.The first part of this important book reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses. Various mathematical (analytical and numerical) methods for calculation of residual stresses in composite materials are also presented. Chapters in the first section of the book discuss the simulated hole drilling method, the slitting/crack compliance method, measuring residual stresses in homogeneous and composite glass materials using photoelastic techniques, and modeling residual stresses in composite materials. The second part of the book discusses residual stresses in polymer matrix, metal-matrix and a range of other types of composites. Moreover, the addition of nanoparticles to the matrix of polymeric composites as a new technique for reduction of residual stresses is discussed.Residual stresses in composite materials provides a comprehensive overview of this important topic, and is an invaluable reference text for both academics and professionals working in the mechanical engineering, civil engineering, aerospace, automotive, marine and sporting industries. - Reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses - Discusses residual stresses in polymer matrix, metal-matrix and other types of composite - Considers the addition of nanoparticles to the matrix of polymeric composites as a new technique for reduction of residual stresses
New Challenges in Residual Stress Measurements and Evaluation
Author: Caterina Casavola
Publisher: BoD – Books on Demand
ISBN: 1789849519
Category : Technology & Engineering
Languages : en
Pages : 158
Book Description
Residual stresses (RS) are stresses present inside materials even in the absence of any applied load. They are of capital importance because they can impact greatly on the mechanical strength of the material, on its dimensional correspondence to design specifications as well as on the fatigue life of the part. RS measurement and evaluation is currently an important research topic where a lot of challenges still need to be addressed. This book aims to provide the reader with an overview of the principal novelties in this field including current limitations and potential future developments. Both radically new experimental approaches as well as recent evolutions of consolidated ones will be presented, along with the latest novelties in the area of numerical residual stress evaluation.
Publisher: BoD – Books on Demand
ISBN: 1789849519
Category : Technology & Engineering
Languages : en
Pages : 158
Book Description
Residual stresses (RS) are stresses present inside materials even in the absence of any applied load. They are of capital importance because they can impact greatly on the mechanical strength of the material, on its dimensional correspondence to design specifications as well as on the fatigue life of the part. RS measurement and evaluation is currently an important research topic where a lot of challenges still need to be addressed. This book aims to provide the reader with an overview of the principal novelties in this field including current limitations and potential future developments. Both radically new experimental approaches as well as recent evolutions of consolidated ones will be presented, along with the latest novelties in the area of numerical residual stress evaluation.
Residual Stresses 2018
Author: Marc Seefeldt
Publisher: Materials Research Forum LLC
ISBN: 1945291893
Category : Technology & Engineering
Languages : en
Pages : 310
Book Description
The European Conference on Residual Stresses (ECRS) series is the leading European forum for scientific exchange on internal and residual stresses in materials. It addresses both academic and industrial experts and covers a broad gamut of stress-related topics from instrumentation via experimental and modelling methodology up to stress problems in specific processes such as welding or shot-peening, and their impact on materials properties. Chapters: Diffraction Methods; Mechanical Relaxation Methods; Acoustic and Electromagnetic Methods; Composites, Nano and Microstructures; Films, Coatings and Oxides; Cold Working and Machining; Heat Treatments and Phase Transformations; Welding, Fatigue and Fracture: Stresses in Additive Manufacturing.
Publisher: Materials Research Forum LLC
ISBN: 1945291893
Category : Technology & Engineering
Languages : en
Pages : 310
Book Description
The European Conference on Residual Stresses (ECRS) series is the leading European forum for scientific exchange on internal and residual stresses in materials. It addresses both academic and industrial experts and covers a broad gamut of stress-related topics from instrumentation via experimental and modelling methodology up to stress problems in specific processes such as welding or shot-peening, and their impact on materials properties. Chapters: Diffraction Methods; Mechanical Relaxation Methods; Acoustic and Electromagnetic Methods; Composites, Nano and Microstructures; Films, Coatings and Oxides; Cold Working and Machining; Heat Treatments and Phase Transformations; Welding, Fatigue and Fracture: Stresses in Additive Manufacturing.
International Conference on Residual Stresses
Author: G. Beck
Publisher: Springer Science & Business Media
ISBN: 9400911432
Category : Technology & Engineering
Languages : en
Pages : 1043
Book Description
Residual stresses are always introduced in materials when they are produced, or when they undergo non-uniform plastic deformation during use. The circumstances that can cause residual stresses are therefore numerous. Residual stresses exist in all materials and, depending on their distribution, can playa beneficial role (for example, compressive surface stress) or have a catastrophic effect, especially on fatigue behaviour and corrosion properties. The subject of residual stresses took form around 1970 with the development of methods to measure macroscopic deformations during the machining of materials or on an atomic scale by X-ray diffraction. These techniques have made considerable progress in the last 20 years. The meetings organized in several countries (Germany, France, Japan, etc. ) have largely contributed to this progress, aided by the numerous exchanges of information and knowledge to which they have given rise. Studies of the formation of residual stresses began more slowly, but have progressed with the emergence of increasingly realistic models of materials behaviour and with access to ever more powerful codes for numerical calculations. Two successive meetings for discussing this topic have been held in Europe. The first, held in 1982 in Nancy (France), consisted of 30 participants from 5 countries. The second was held in Linkoping (Sweden) in 1984, with 80 participants of 16 nationalities. It was decided to hold a first International Conference, ICRS, to address all aspects of the problem. Held in 1986 in Garmisch-Partenkirschen (FRG), it was an assembly of neady 300 participants from 21 countries.
Publisher: Springer Science & Business Media
ISBN: 9400911432
Category : Technology & Engineering
Languages : en
Pages : 1043
Book Description
Residual stresses are always introduced in materials when they are produced, or when they undergo non-uniform plastic deformation during use. The circumstances that can cause residual stresses are therefore numerous. Residual stresses exist in all materials and, depending on their distribution, can playa beneficial role (for example, compressive surface stress) or have a catastrophic effect, especially on fatigue behaviour and corrosion properties. The subject of residual stresses took form around 1970 with the development of methods to measure macroscopic deformations during the machining of materials or on an atomic scale by X-ray diffraction. These techniques have made considerable progress in the last 20 years. The meetings organized in several countries (Germany, France, Japan, etc. ) have largely contributed to this progress, aided by the numerous exchanges of information and knowledge to which they have given rise. Studies of the formation of residual stresses began more slowly, but have progressed with the emergence of increasingly realistic models of materials behaviour and with access to ever more powerful codes for numerical calculations. Two successive meetings for discussing this topic have been held in Europe. The first, held in 1982 in Nancy (France), consisted of 30 participants from 5 countries. The second was held in Linkoping (Sweden) in 1984, with 80 participants of 16 nationalities. It was decided to hold a first International Conference, ICRS, to address all aspects of the problem. Held in 1986 in Garmisch-Partenkirschen (FRG), it was an assembly of neady 300 participants from 21 countries.