Multi Scale Invertigation Of The Relationship Between The Microstructure And Mechanical Properties In Dual Phase Steels

Dual phase steel alloys belong to the first generation of advanced high strength steels that are widely used in the automotive industry to form body structure and closure panels of vehicles. A deeper understanding of the microstructural features, such as phase orientation and morphology are needed in order to establish their effect on the mechanical performance and to design a material with optimized attributes.

The goal of this thesis is to investigate the relationship between microstructure properties and mechanical properties of dual phase (DP) steels to design advanced materials for automotive applications. In this research, a new effective analytical methodology that studies the influences and interactions of microstructure properties on the mechanical behavior of DP steels under different strain rates was developed. In this work, the plastic deformation of multiphase material with different microstructures including volume fraction and grain size of phases, and carbon content in DP steels etc., under different strain rates was investigated.

This volume highlights the latest advances, innovations, and applications in the field of metal forming, as presented by leading international researchers and engineers at the 14th International Conference on Technology of Plasticity (ICTP), held in Mandelieu-La Napoule, France on September 24-29, 2023. It covers a diverse range of topics such as manufacturing processes & equipment, materials behavior and characterization, microstructure design by forming, surfaces & interfaces, control & optimization, green / sustainable metal forming technologies, digitalization & AI in metal forming, multi-material processing, agile / flexible metal forming processes, forming of non-metallic materials, micro-forming and luxury applications. The contributions, which were selected by means of a rigorous international peer-review process, present a wealth of exciting ideas that will open novel research directions and foster multidisciplinary collaboration among different specialists.

"Advanced Steels: The Recent Scenario in Steel Science and Technology" contains more than 50 articles selected from the proceedings of the International Conference on Advanced Steels (ICAS) held during 9-11, Nov, 2010 in Guilin, China. This book covers almost all important aspects of steels from physical metallurgy, steel grades, processing and fabrication, simulation, to properties and applications. The book is intended for researchers and postgraduate students in the field of steels, metallurgy and materials science. Prof. Yuqing Weng is an academician of Chinese Academy of Engineering and the president of The Chinese Society for Metals. Prof. Han Dong is the vice president of Central Iron & Steel Research Institute and the director of National Engineering Research Center of Advanced Steel Technology, China. Prof. Yong Gan is an academician of Chinese Academy of Engineering, the vice president of Chinese Academy of Engineering and the president of Central Iron & Steel Research Institute, China.

This book represents a collection of papers presented at the 2nd World Congress on Integrated Computational Materials Engineering (ICME), a specialty conference organized by The Minerals, Metals & Materials Society (TMS).

Quantitative relationships among processing parameters, microstructure, and material properties are of considerable interest in the context of development of robust processing routes that optimize the required material properties. As a result, the scientific literature contains a large number of experimental and theoretical studies on microstructure-properties relationships. Fracture sensitive mechanical properties such as ductility, ultimate tensile strength, fatigue life, and fracture toughness depend on the average microstructural parameters as well as the distributions of microstructural parameters and their extrema. Development of quantitative relationships between such material properties and microstructural distributions and extrema has received considerably less attention, particularly in the wrought metals and alloys. Accordingly, an important objective of this research is to perform a systematic investigation in this direction. The dependence of the fracture-sensitive mechanical properties on the microstructural distributions and extrema often leads to substantial variability in these properties: a set of specimens having the same average chemistry, the same average processing history, and the same average microstructural parameters such as volume fractions of different constituents can exhibit substantially different material properties. The present research (i) is concerned with high strength (~ 1000 MPa) high martensite (>50%) dual phase steel where the martensite is a topologically continuous phase (matrix) containing a dispersion of islands of ferrite, and (ii) focuses on understanding the microstructural origins of the variability in fracture sensitive mechanical properties, in particular variability in the room temperature uniaxial tensile ductility. The research involves quantitative microstructure characterization using stereology and digital image processing and quantitative fractography using scanning electron microscopy (SEM) and fracture profilometry. The analysis of the quantitative fractographic and microstructural data obtained in this research leads to useful guidelines for reducing the variability in the tensile ductility of the dual phase steel under investigation.

This book presents current spatial and temporal multiscaling approaches of materials modeling. Recent results demonstrate the deduction of macroscopic properties at the device and component level by simulating structures and materials sequentially on atomic, micro- and mesostructural scales. The book covers precipitation strengthening and fracture processes in metallic alloys, materials that exhibit ferroelectric and magnetoelectric properties as well as biological, metal-ceramic and polymer composites. The progress which has been achieved documents the current state of art in multiscale materials modelling (MMM) on the route to full multi-scaling. Contents: Part I: Multi-time-scale and multi-length-scale simulations of precipitation and strengthening effects Linking nanoscale and macroscale Multiscale simulations on the coarsening of Cu-rich precipitates in α-Fe using kinetic Monte Carlo, Molecular Dynamics, and Phase-Field simulations Multiscale modeling predictions of age hardening curves in Al-Cu alloys Kinetic Monte Carlo modeling of shear-coupled motion of grain boundaries Product Properties of a two-phase magneto-electric composite Part II: Multiscale simulations of plastic deformation and fracture Niobium/alumina bicrystal interface fracture Atomistically informed crystal plasticity model for body-centred cubic iron FE2AT ・ finite element informed atomistic simulations Multiscale fatigue crack growth modeling for welded stiffened panels Molecular dynamics study on low temperature brittleness in tungsten single crystals Multi scale cellular automata and finite element based model for cold deformation and annealing of a ferritic-pearlitic microstructure Multiscale simulation of the mechanical behavior of nanoparticle-modified polyamide composites Part III: Multiscale simulations of biological and bio-inspired materials, bio-sensors and composites Multiscale Modeling of Nano-Biosensors Finite strain compressive behaviour of CNT/epoxy nanocomposites Peptide・zinc oxide interaction

Presenting the results of an ambitious project, this book summarizes the efforts towards an open, web-based modular and extendable simulation platform for materials engineering that allows simulations bridging several length scales. In so doing, it covers processes along the entire value chain and even describes such different classes of materials as metallic alloys and polymers. It comprehensively describes all structural ideas, the underlying concepts, standard specifications, the verification results obtained for different test cases and additionally how to utilize the platform as a user and how to join it as a provider. A resource for researchers, users and simulation software providers alike, the monograph provides an overview of the current status, serves as a generic manual for prospective users, and offers insights into the inner modular structure of the simulation platform.