Author: Andrew Francis SzewczykPublisher:
ISBN:
Category : Steel
Languages : en
Pages : 122
Book Description
An Investigation of the Tensile Deformation and Fracture of a Dual-phase Steel
Author: Andrew Francis SzewczykPublisher:
ISBN:
Category : Steel
Languages : en
Pages : 122
Book Description
Uniaxial Tensile Deformation and Fracture of Dual-phase Steels
Author: Yean-Liang SuScientific and Technical Aerospace Reports
Author: Energy Research Abstracts
Author: The Causes of "shear Fracture" of Dual-phase Steels
Author: Ji-Hyun SungPublisher:
ISBN:
Category :
Languages : en
Pages : 207
Book Description
Abstract: Dual Phase (DP) steels are a class of advanced high strength steel (AHSS) in increasing use for sheet formed automotive parts. In spite of attractive combinations of high strength, high ductility, and low cost, the widespread adoption of DP steels has been limited because practical die tryouts exhibit forming failures far earlier than predicted by standard industrial methods. These failures, often referred to as "shear fractures," occur in regions of high curvature and with little apparent necking, in contrast to "normal" or tensile fractures. Conventional wisdom attributes shear fractures to a postulated damage mechanism related to the special microstructure of DP steels. In order to reproduce, characterize, and analyze such fractures in a laboratory setting and to understand their origin of the inability to predict them, a novel draw-bend formability (DBF) test was devised based on displacement control. DP steels from several suppliers with tensile strengths ranging from 590 to 980 MPa were tested over a range of rates and bend ratios (R/t, inner bend radius / sheet thickness). The new DBF test reliably reproduced three kinds of fractures identified as Type I, II, and III, corresponding to tensile fracture, transitional fracture, and shear fracture, respectively. These tests revealed a surprising result: the occurrence of shear fractures increased at higher deformation rates. This degradation of formability was shown to be principally a result of deformation-induced heating, which is greatly accentuated for AHSS because of their high plastic energy absorption and commensurate high temperature increases, up to 100 degrees C. In order to understand and quantify the role of deformation-induced heating on plastic localization, temperatures were measured and simulated using a novel new empirical plasticity constitutive form describing the flow stress as a function of strain, strain-rate, and temperature. Designated the "H/V model", the new constitutive model consists of three multiplicative functions describing (a) strain hardening and its temperature sensitivity, (b) strain-rate sensitivity, and (c) temperature sensitivity. This form allows a natural transition from unbounded strain hardening at low temperatures toward saturation behavior at higher temperatures, consistent with many observations. Thermo-mechanical finite-element simulations using the H/V model confirmed its accuracy and the magnitude of the role on shear fracture. Failure types were predicted, as well as quantitative. For most of the DP steels tested, heating induced by deformation was identified as the dominant effect in producing unpredicted fractures. This is a result of standard industrial techniques that do not take non-isothermal effect into account, in particular constructing forming limit diagrams from low-speed / isothermal testing, and use of isothermal finite element modeling to analyze industrial sheet forming operations. Microstructural damage can also contribute to shear fracture, but it was a secondary factor for all but one of the alloys tested, in one test direction.
ERDA Energy Research Abstracts
Author: Mechanical Behavior of High-Strength Low-Alloy Steels
Author: Ricardo BrancoPublisher: MDPI
ISBN: 3038972045
Category : Technology & Engineering
Languages : en
Pages : 220
Book Description
This book is a printed edition of the Special Issue "Mechanical Behavior of High-Strength Low-Alloy Steels" that was published in Metals
Masters Theses in the Pure and Applied Sciences Accepted by Colleges and Universities of the United States and Canada
Author: Wade H. ShaferPublisher: Springer
ISBN: 9780306416613
Category : Science
Languages : en
Pages : 354
Book Description
This series lists applicable thesis titles published in the United States and Canada. Volume 40 covers thesis year 1995. All back volumes are still available.
TMS 2018 147th Annual Meeting & Exhibition Supplemental Proceedings
Author: The Minerals, Metals & Materials SocietyPublisher: Springer
ISBN: 3319725262
Category : Technology & Engineering
Languages : en
Pages : 898
Book Description
This collection features papers presented at the 147th Annual Meeting & Exhibition of The Minerals, Metals & Materials Society.
Dynamic Behavior of Materials, Volume 1
Author: Jamie KimberleyPublisher: Springer
ISBN: 3319629565
Category : Science
Languages : en
Pages : 234
Book Description
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