Download Free Influence Of Micromechanical Mechanisms On Strength And Damage Of Tool Steels Under Static And Cyclic Loading Book in PDF and EPUB Free Download. You can read online Influence Of Micromechanical Mechanisms On Strength And Damage Of Tool Steels Under Static And Cyclic Loading and write the review.

Tool steels serve a large range of applications in hot and coId working of metals as well as injection moulding of plastics or light alloys. Ledeburitic tool steels are mainly used in coId working operation where an extremely high wear resistance is requested. Therefore, these steels present coarse and very hard primary alloyed (Iedeburitic) carbides. Non-ledeburitic tool steels have a still wider range of use in hot working and especially in warm or hot injection moulding. The carbides in these steels are very fine secondary microcarbides. For these two categories of steel, the industrial need is to optimise the compromise between high mechanical resistance levels and better response to both static and cyclic loadings. For ledeburitic tool steels, numerical modelling of realistic microstructures is able to calculate the stress distributions and concentrations resulting from the heterogeneity in terms of carbide size, shape and distribution, as well as the topological characteristics of the fracture surface. The report outlines the development of analytical and numerical models leading to predict the influence of microstructure on fracture toughness of ledeburitic tool steels. This prediction is compared to experimental results on forged bars from ingots and HIPed powder metallurgy products. Although the comparison of sensitive parameters between experimental, analytical and numerical results is not always consistent, the agreement existing on the favourable role of net-like structure of primary carbides and on the increase of toughness with the fracture surface roughness offers the possibility to use numerical modelling to find the optimal microstructure.
The strength of metallic materials determines the usability and reliability of all the machines, tools and equipment around us. Yet, the question about which mechanisms control the strength and damage resistance of materials and how they can be optimised remains largely unanswered. How do real, heterogeneous ma- rials deform and fail? Why can a small modification of the microstructure increase the strength and damage resistance of materials manifold? How can the strength of heterogeneous materials be predicted? The purpose of this book is to present different experimental and computational analysis methods of micromechanics of damage and strength of materials and to demonstrate their applications to various micromechanical problems. This book summarizes at a glance some of the publications of the Computational Mechanics Group at the IMWF/MPA Stuttgart, dealing with atomistic, micro- and meso- chanical modelling and experimental analysis of strength and damage of metallic materials. In chapter 1, the micromechanisms of damage and fracture in different groups of materials are investigated experimentally, using direct observations and inverse analysis. The interaction of microstructural elements with the evolving damage is studied in these experiments. Chapter 2 presents different approaches to the - cromechanical simulation of composite materials: embedded unit cells, multiphase finite elements and multiparticle unit cells. Examples of the application of these models to the analysis of deformation and damage in different materials are given. Chapter 3 deals with the methods of numerical modelling of damage evolution and crack growth in heterogeneous materials.
Mechanical properties of composite materials can be improved by tailoring their microstructures. Optimal microstructures of composites, which ensure desired properties of composite materials, can be determined in computational experiments. The subject of this book is the computational analysis of interrelations between mechanical properties (e.g., strength, damage resistance stiffness) and microstructures of composites. The methods of mesomechanics of composites are reviewed, and applied to the modelling of the mechanical behaviour of different groups of composites. Individual chapters are devoted to the computational analysis of the microstructure- mechanical properties relationships of particle reinforced composites, functionally graded and particle clusters reinforced composites, interpenetrating phase and unidirectional fiber reinforced composites, and machining tools materials.
Steels are by far the most important construction materials for many applications. Many modern concepts of materials science are being used in steels, e.g., in micro-alloyed steels minute amounts of alloying elements form nanoscale carbides to yield superior strength values. All of these mechanisms have to be controlled in the production facilities on a scale of hundreds of tons. This book addresses these new concepts for improving the efficiency of production technologies
In this thesis Christian Sohar describes his investigation into the gigacycle fatigue behavior of tool steels. In an interdisciplinary approach he uses knowledge and methods from a wide variety of disciplines including materials science, metallurgy, chemistry, physics and mechanical engineering. Christian gives a general introduction into steel tools and fatigue in materials. Later he extensively discusses the experimental techniques and results. Indeed it is the detail of the content in this thesis which makes it an invaluable resource for students entering the field and scientists working in related disciplines. Overall, the thesis helps us understand more about the mechanical behavior of metallic materials with complex microstructure and high hardness.
High-performance alloys that can withstand operation in hazardous nuclear environments are critical to presentday in-service reactor support and maintenance and are foundational for reactor concepts of the future. With commercial nuclear energy vendors and operators facing the retirement of staff during the coming decades, much of the scholarly knowledge of nuclear materials pursuant to appropriate, impactful, and safe usage is at risk. Led by the multi-award winning editorial team of G. Robert Odette (UCSB) and Steven J. Zinkle (UTK/ORNL) and with contributions from leaders of each alloy discipline, Structural Alloys for Nuclear Energy Applications aids the next generation of researchers and industry staff developing and maintaining steels, nickel-base alloys, zirconium alloys, and other structural alloys in nuclear energy applications. This authoritative reference is a critical acquisition for institutions and individuals seeking state-of-the-art knowledge aided by the editors’ unique personal insight from decades of frontline research, engineering and management. Focuses on in-service irradiation, thermal, mechanical, and chemical performance capabilities. Covers the use of steels and other structural alloys in current fission technology, leading edge Generation-IV fission reactors, and future fusion power reactors. Provides a critical and comprehensive review of the state-of-the-art experimental knowledge base of reactor materials, for applications ranging from engineering safety and lifetime assessments to supporting the development of advanced computational models.
This book resulted from a series of lecture notes presented in CISM, Udine in July 7 -11, 2008. The papers inform about recent advances in continuum damage mechanics for both metals and metal matrix composites as well as the micromechanics of localization in inelastic solids. Also many of the different constitutive damage models that have recently appeared in the literature and the different approaches to this topic are presented, making them easily accessible to researchers and graduate students in civil engineering, mechanical engineering, engineering mechanics, aerospace engineering, and material science.