1. |
Max‐Planck‐Institut für Eisenforschung GmbH Department of Physical Metallurgy |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 95-99
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ISSN:0003-8962
DOI:10.1002/srin.198600733
出版商:Wiley
年代:2016
数据来源: WILEY
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2. |
Some remarks on the recent development of the foundations of the theory of plasticity |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 101-107
Theodor Lehmann,
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摘要:
In this paper some aspects of the recent development of the phenomenological theory of plasticity are reviewed. Deformation processes running with finite rate represent coupled thermo‐mechanical processes. Therefore the theory of plasticity has to be embedded into a consistent thermodynamical frame. How this can be done is sketched for a simple material model. The bounds of this thermodynamical frame result from the assumption that the thermodynamical state of each material element is describable by a set of external and internal state variables at any time. Concerning the rate dependence of deformation processes two different kinds of phenomena can be distinguished:Phenomena representing internal damping (viscous) effects which are responsible for short‐time creep processes among others; they are characterized by the existence of constraint thermodynamical equilibrium states.Phenomena due to thermal activation essentially; they are prevailing at higher homologous temperature leading to long‐time creep processes among others.In inelastic deformations different yield mechanisms are involved. Regarding these facts more complex material models are required exhibiting some generalizations of the classical theory of plasticity. Particularly certain deviations from the so‐called normality rule have to be taken into account.Another kind of coupling between thermal and mechanical processes arises from occuring heat conduction as soon as the temperature field becomes inhomogeneous. This kind of coupling particularly affects the localization of deformations as, for instance, in the necking problem in tension tests. Furthermore local damage and fracture have to be considered as coupled thermo‐mechanical problems.
ISSN:0003-8962
DOI:10.1002/srin.198600734
出版商:Wiley
年代:2016
数据来源: WILEY
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3. |
ECSC announcements |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 107-108
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PDF (249KB)
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ISSN:0003-8962
DOI:10.1002/srin.198600735
出版商:Wiley
年代:2016
数据来源: WILEY
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4. |
On finite element methods in metal working |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 109-116
Oskar Mahrenholtz,
Nguyen Luong Dung,
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摘要:
In metal forming industries, many products are to be formed in large number and with highly accurate dimensions. To save energy and material it is necessary to understand the behaviour of material and to know the intermediate shapes of the formed parts and the mutual effects between tool and formed part during the forming process. The design of the tool and the manufacturing procedures are increasingly carried out by computer aided design and manufacturing (CAD/CAM). These procedures are normally based on numerical methods which take into account all physical conditions of the deformed material during the process. For this purpose, finite element methods (FEM) have been developed in the past in different ways. This paper highlights some of these methods which are particularly effective in simulating the forming processes.
ISSN:0003-8962
DOI:10.1002/srin.198600736
出版商:Wiley
年代:2016
数据来源: WILEY
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5. |
Status of research on the plastomechanical fundamentals of rolling and drawing processes |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 117-123
Oskar Pawelski,
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摘要:
Among the processes for plastic deformation of steel, rolling of strip, plate, and sections, and drawing of wire, bars, and tubes are of great importance. A survey is given showing to what extent the plastomechanical fundamentals of these forming methods have been developed. Theory is mainly directed towards the calculation of the deformation force and the flow of material. The governing influences are of geometrical, kinematical, thermal, tribological, and material‐scientific kind. Starting from the basic equations of continuum mechanics, the mathematical methods of similitude, visioplasticity, energy bounds, elementary plasticity, slip line fields, and finite elements are briefly characterized.
ISSN:0003-8962
DOI:10.1002/srin.198600737
出版商:Wiley
年代:2016
数据来源: WILEY
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6. |
ECSC announcements |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 123-124
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PDF (230KB)
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ISSN:0003-8962
DOI:10.1002/srin.198600738
出版商:Wiley
年代:2016
数据来源: WILEY
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7. |
The theory of open‐die forging in the course of historical change |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 125-129
Reiner Kopp,
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摘要:
The forging process – originating empirically – can nowadays be understood with the aid of a series of theoretical approaches within the field of metalforming technology. The classic methods (chiefly slip lines) have contributed to fundamental knowledge of the process. Parameters like force and energy requirement, performance and deformation resistance can be determined with sufficient accuracy by these means. Quantitative analyses of localised processes are, however, possible only with the aid of FE methods, though satisfactory solutions have not yet been found to the problems of applying 3 D FEM and taking into account the real boundary conditions.
ISSN:0003-8962
DOI:10.1002/srin.198600739
出版商:Wiley
年代:2016
数据来源: WILEY
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8. |
ECSC announcements |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 130-130
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PDF (115KB)
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ISSN:0003-8962
DOI:10.1002/srin.198600740
出版商:Wiley
年代:2016
数据来源: WILEY
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9. |
Application of fracture mechanics concepts to the failure of steel constructions |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 131-134
Winfried Dahl,
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摘要:
The failure behaviour of wide plates with different defect geometry was investigated experimentally and quantitatively described by FE‐calculations based on material properties, which were determined with small‐scale specimens. It is shown, that in the temperature range where brittle, elastic‐plastic and fully plastic failure of the wide plates occurs, the fracture behaviour can be predicted sufficiently precisely based on fracture mechanics parameters in terms of theJ‐Integral. These predictions require an exact evaluation of the material properties, such as stress‐strain‐curve and critical fracture mechanics values and, on the other side, of the loading conditions calculated in terms ofJl.
ISSN:0003-8962
DOI:10.1002/srin.198600741
出版商:Wiley
年代:2016
数据来源: WILEY
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10. |
ECSC announcements |
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Archiv für das Eisenhüttenwesen,
Volume 57,
Issue 3,
2016,
Page 134-134
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PDF (91KB)
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ISSN:0003-8962
DOI:10.1002/srin.198600742
出版商:Wiley
年代:2016
数据来源: WILEY
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