Author: Xiaosheng GaoPublisher:
ISBN:
Category :
Languages : en
Pages : 428
Book Description
Numerical Modeling of Crack Growth in Ductile-brittle Transition Regime
Author: Xiaosheng GaoDuctile Crack Growth Analysis Within the Ductile-Brittle Transition Regime
Author: I. MilnePublisher:
ISBN:
Category : Ductile crack extension
Languages : en
Pages : 13
Book Description
The ductile-brittle transition in ferritic steels is reviewed using data from pressure vessel steels A533B, A508, BS1501-271, and their associated weld metals and heat-affected zones in a variety of conditions. A schematic model is presented which provides a rational basis for understanding the phenomenon and making predictions. This model, which is consistent with the predictions obtained from physical models of cleavage fracture, contains the following important features. 1. If in the transition regime, KIc is defined as the fracture toughness at the onset of the brittle mode of fracture and KIJ is defined as the fracture toughness at the onset of ductile crack growth, then KIc > KIJ. 2. The ductile crack extension obtained between the initiation of ductile crack growth and the onset of brittle fracture is defined by the elastic-plastic crack growth resistance curve. 3. KIc cannot be reached without generating the appropriate amount of ductile crack extension.
Numerical Modeling of Ductile Tearing Effects on Cleavage Fracture Toughness
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 33
Book Description
Experimental studies demonstrate a significant effect of specimen size, a/W ratio and prior ductile tearing on cleavage fracture toughness values (J{sub c}) measured in the ductile-to-brittle transition region of ferritic materials. In the lower-transition region, cleavage fracture often occurs under conditions of large-scale yielding but without prior ductile crack extension. The increased toughness develops when plastic zones formed at the crack tip interact with nearby specimen surfaces which relaxes crack-tip constraint (stress triaxiality). In the mid-to-upper transition region, small amounts of ductile crack extension (often
Numerical Modeling of Ductile Tearing Effects on Cleavage Fracture Toughness
Author: Robert H. DoddsPublisher:
ISBN:
Category : Fracture mechanics
Languages : en
Pages : 32
Book Description
From Charpy to Present Impact Testing
Author: D. FrancoisPublisher: Elsevier
ISBN: 008052897X
Category : Technology & Engineering
Languages : en
Pages : 497
Book Description
From Charpy to Present Impact Testing contains 52 peer-reviewed papers selected from those presented at the Charpy Centenary Conference held in Poitiers, France, 2-5 October 2001. The name of Charpy remains associated with impact testing on notched specimens. At a time when many steam engines exploded, engineers were preoccupied with studying the resistance of steels to impact loading. The Charpy test has provided invaluable indications on the impact properties of materials. It revealed the brittle ductile transition of ferritic steels. The Charpy test is able to provide more quantitative results by instrumenting the striker, which allows the evolution of the applied load during the impact to be determined. The Charpy test is of great importance to evaluate the embrittlement of steels by irradiation in nuclear reactors. Progress in computer programming has allowed for a computer model of the test to be developed; a difficult task in view of its dynamic, three dimensional, adiabatic nature. Together with precise observations of the processes of fracture, this opens the possibility of transferring quantitatively the results of Charpy tests to real components. This test has also been extended to materials other than steels, and is also frequently used to test polymeric materials. Thus the Charpy test is a tool of great importance and is still at the root of a number of investigations; this is the reason why it was felt that the centenary of the Charpy test had to be celebrated. The Société Française de Métallurgie et de Matériaux decided to organise an international conference which was put under the auspices of the European Society for the Integrity of Structures (ESIS). This Charpy Centenary Conference (CCC 2001) was held in Poitiers, at Futuroscope in October 2001. More than 150 participants from 17 countries took part in the discussions and about one hundred presentations were given. An exhibition of equipment showed, not only present day testing machines, but also one of the first Charpy pendulums, brought all the way from Imperial College in London. From Charpy to Present Impact Testing puts together a number of significant contributions. They are classified into 6 headings: •Keynote lectures,•Micromechanisms,•Polymers,•Testing procedures,•Applications,•Modelling.
Multi-scale Simulation of Crack Propagation in the Ductile-brittle Transition Region
Author: Geralf HütterNumerical Models of Ductile Crack Growth
Author: Annika TrädegårdComprehensive Structural Integrity
Author: Ian MilnePublisher: Elsevier
ISBN: 0080490735
Category : Business & Economics
Languages : en
Pages : 4647
Book Description
The aim of this major reference work is to provide a first point of entry to the literature for the researchers in any field relating to structural integrity in the form of a definitive research/reference tool which links the various sub-disciplines that comprise the whole of structural integrity. Special emphasis will be given to the interaction between mechanics and materials and structural integrity applications. Because of the interdisciplinary and applied nature of the work, it will be of interest to mechanical engineers and materials scientists from both academic and industrial backgrounds including bioengineering, interface engineering and nanotechnology. The scope of this work encompasses, but is not restricted to: fracture mechanics, fatigue, creep, materials, dynamics, environmental degradation, numerical methods, failure mechanisms and damage mechanics, interfacial fracture and nano-technology, structural analysis, surface behaviour and heart valves. The structures under consideration include: pressure vessels and piping, off-shore structures, gas installations and pipelines, chemical plants, aircraft, railways, bridges, plates and shells, electronic circuits, interfaces, nanotechnology, artificial organs, biomaterial prostheses, cast structures, mining... and more. Case studies will form an integral part of the work.
Numerical Simulations of Ductile Crack Growth in Thin Specimens Based on a Cohesive Zone Model
Author: Alfred CornecModeling of Defects and Fracture Mechanics
Author: G. HerrmannPublisher: Springer
ISBN: 3709127165
Category : Science
Languages : en
Pages : 211
Book Description
All materials contain numerous defects, such as microcracks, microvoids, inhomogeneities, dislocations, etc., which precede possible fracture. Thus mathematical modeling becomes necessary. This volume contains some introductory material, aspects of fracture mechanics, the theory of crystal defects, computational micromechanics, and the heterogenization methodology.