Effect Of Different Strain Paths On Mechanical Behavior Of Dual Phase Sheet Steel

Dual-phase steels exhibit good mechanical properties due to a microstructure of strong martensitic inclusions embedded in a ductile ferritic matrix. This work presents a two-scale model for the underlying work-hardening effects; such as the distinctly different hardening rates observed for high-strength dual-phase steels. The model is based on geometrically necessary dislocations and comprises the average microstructural morphology as well as a direct interaction between the constituents.

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 collection provides researchers and industry professionals with complete guidance on the synthesis, analysis, design, monitoring, and control of metals, materials, and metallurgical processes and phenomena. Along with the fundamentals, it covers modeling of diverse phenomena in processes involving iron, steel, non-ferrous metals, and composites. It also goes on to examine second phase particles in metals, novel sensors for hostile-environment materials processes, online sampling and analysis techniques, and models for real-time process control and quality monitoring systems.

This book is a printed edition of the Special Issue "Mechanical Behavior of High-Strength Low-Alloy Steels" that was published in Metals

This proceedings brings together one hundred and ten selected papers presented at the 2nd International Conference on Advanced High Strength Steel and Press Hardening (ICHSU2015), which was held in Changsha, China, during October 15-18, 2015.To satisfy the increasingly urgent requirement of reducing the weight of vehicle structures and increasing passenger safety, ICHSU2015 provided an excellent international platform for researchers to share their knowledge and results in theory, methodology and applications of advanced high strength steel and press hardening technology.This conference aroused great interests and attentions from domestic and foreign researchers in hot stamping field. Experts in this field from Australia, China, Germany and Sweden, contributed to the collection of research results and developments. The papers cover almost all the current topics of advanced high strength steel and press hardening technology.

New Dual-Phase (DP) steel sheet with desirable mechanical properties are developed using trialand-error methods that are time-consuming and expensive. Using only micro-structural information, methods to predict stress-strain under tension, reverse yield under compression following tensile loading, and a lower-bound formability limit diagram (FLD) are developed. Mean-field models were used to obtain the flow behavior of the composite under uni-axial loading and reverse yielding, and also serve as descriptors of stress-strain behavior of the ferrite and martensite phases in the finite element models. Representative Volume Elements (RVEs) of the steel were used for the creation of a morphologically realistic Finite Element Model, which in turn allows prediction of flow behavior under uni-axial and plane strain loading. The latter allows estimation of the FLD using the Marciniak-Kuczynski (M-K) and Modified Maximum Force Criterion (MMFC) approaches. Computations with the RVE models afford insights into the relationship between the microstructure and mechanical properties.

Dynamic Behavior of Materials, Volume 1 of the Proceedings of the 2017 SEM Annual Conference& Exposition on Experimental and Applied Mechanics, the first volume of nine from the Conference, brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Experimental Mechanics, including papers on: Quantitative Visualization Fracture & Fragmentation Dynamic Behavior of Low Impedance Materials Shock & Blast Dynamic Behavior of Composites Novel Testing Techniques Hybrid Experimental & Computational Methods Dynamic Behavior of Geo-materials General Material Behavior

The investigation of thermo-mechanical and thermal treatments on the microstructure and mechanical behavior of DP590 and TRIP680 steels revealed several critical aspects of the materials' responses to different testing. Various thermo-mechanical treatments were carried out to identify the responses to the said treatments. Following these preconditioning protocols, quasi-static, and high strain-rate tests showed how the materials reacted under tensile testing to fracture. Ensuing heat treatments on the as-received materials were performed to bring about phase fraction changes to each of the steels. These heat-treated DP and TRIP steels were examined to discover microstructural characteristics and mechanical responses through quasi-static and high strain-rate testing. The responses of the steels were analyzed and compared to the as-received testing results to observe the significant changes of mechanical behavior that occurred.