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Fundamental Aspects of Dislocation Interactions: Low-Energy Dislocation Structures III

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Table of Contents

Preface

Organizing Committee

Chapter 1. Work softening and Hall-Petch hardening in extruded mechanically alloyed alloys

1. Introduction

2. Stress-strain behavior in relation to composition, structure and annealing

3. Microstructures in A3 after deformation

4. Comparison of stress-strain curves with work softening theory

5. Interpretation of the micrographie observations

Acknowledgments

References

Chapter 2. On the dynamic origin of dislocation structures in deformed solids

1. Introduction

2. Sweeping and trapping mechanism

3. Model of dipolar wall structure formation

4. Coupling to the stress field

5. Summary

References

Chapter 3. Modelling the spatiotemporal aspects of the Portevin-Le Châtelier effect

1. Introduction

2. Propagation mechanisms

3. Formulation

4. Conclusions

References

Chapter 4. Plastic instabilities and their relation to fracture

1. Introduction

2. Heterogeneous deformation in monotonie loading: influence on toughness

3. Heterogeneous deformation in fatigue and the Coffin-Manson law

4. A second example of damage percolation: ductility of a brittle poIycrystal

Conclusion

Acknowledgments

References

Chapter 5. Dislocation and kink dynamics in f.c.c. metals studied by mechanical spectroscopy

1. Introduction

2. Anelasticity and dislocation damping

3. Experimental techniques

4. Kink dynamics

5. Discussion

6. Conclusions

References

Chapter 6. Screened disclinations in solids

1. Introduction

2. Some simple geometrical properties of disclinations

3. Disclinations and structure levels of plastic flow

4. Different approaches to the calculation of energetic properties of disclinations

5. Screened straight disclinations in an infinite continuum

6. Disclination loops in an infinite continuum

7. External screening for disclination defects

8. Screened disclinations in rotational structures in crystalline solids

9. Disclination mechanisms of plastic deformation and hardening

10. Disclinations in non-crystalline materials

11. Conclusions

Acknowledgments

References

Chapter 7. Mechanisms of yield stress anomalies in beryllium and Ni3 Al

1. Introduction

2. Peierls mechanism and the locking-unlocking mechanism

3. The yield stress anomaly in beryllium

4. The yield stress anomaly in Ni3Al-type ordered alloys

5. Conclusions

References

Chapter 8. Collective behavior and superdislocation motion in Ll2 alloys

1. Introduction

2. The model

3. Results

4. Non-equilibrium phase transition and primary creep

5. Simplified superdislocation model

6. Discussion and conclusions

Acknowledgment

References

Chapter 9. Structure and characterization of the dislocations in tilt grain boundaries between ∑ = 1 and ∑ = 3: a high resolution electron microscopy study

1. Introduction

2. Structure of favoured and intermediate GBs

3. Characterization of the SU/GBD

4. SU Burgers vector evolution

5. Conclusion

References

Chapter 10. Misfit dislocation generation mechanisms in heterostructures

1. Introduction

2. Theoretical and experimental background

3. Constrained-equilibrium model

4. Application of the model

5. Discussion

6. Concluding remarks

Acknowledgments

References

Chapter 11. Evolution of dislocation structure on the interfaces associated with diffusionless phase transitions

1. Introduction

2. Transformation dislocations

3. Equation of equilibrium of an elastic domain

4. Dislocation representation of a wall of elastic domains

Acknowledgments

References

Chapter 12. Dislocation loops at crack tips: nucleation and growth— an experimental study in silicon

1. Introduction

2. Experimental details

3. Summary of observations [9–12]

4. The nature and shape of loops emitted at crack tips

5. Dislocation nucleation and possible source configurations

References

Chapter 13. Dislocation dynamics and brittle-to-ductile transitions

1. Background

2. Static and dynamic models

3. Application of dynamic models

4. Stable crack growth

5. Summary

Acknowledgments

References

Chapter 14. Internal stresses and scaling laws

1. Introduction

2. The internal stress due to dislocations

3. Conclusion

References

Chapter 15. Deformation, structure and properties of ceramics and crystals of high-Tc superconductors

1. Introduction

2. Problems of deformation of HTSCs and experimental details

3. Deformation of HTSC ceramics and single crystals

4. Microhardness of HTSCs

5. Change of the structure under indentation

6. Mechanical properties of fullerite C60

7. Conclusion

Acknowledgments

References

Chapter 16. Structure and mobility of polygonized dislocation walls in high purity aluminium

1. Introduction

2. Experimental conditions

3. Experimental results

4. Discussion

5. Conclusions

Acknowledgment

References

Chapter 17. Deformation mechanisms of a ferritic-martensitic steel between 290 and 870 K

1. Introduction

2. Experimental procedure

3. Results

4. Discussion of results

5. Conclusion

Acknowledgment

References

Chapter 18. On the effect of nitrogen on the dislocation structure of austenitic stainless steel

1. Introduction

2. Experimental details

3. Results

4. Discussion

5. Summary

References

Chapter 19. Dislocation cell structures in copper in torsion and tension

1. Introduction

2. Experimental methods

3. Experimental results

4. Discussion

5. Conclusions

References

Chapter 20. Dislocation distributions as seen by X-ray line profiles

1. Introduction

2. X-ray diffraction technique

3. Tensile deformed [001]-orientated copper single crystals cf.refs. 1,6

4. Fatigued copper polycrystals

5. Wire-drawn copper single crystals

6. The behaviour of residual long-range internal stresses as a function of strain

7. Conclusions

Acknowledgments

References

Chapter 21. The influence of dislocations on electrical resistivity anomalies in palladium alloys

1. Introduction

2. Experimental details

3. Results

4. Discussion

5. Summary and concluding remarks

Acknowledgments

References

Chapter 22. Dislocation structure in Ll2 long-range-ordered Ni3(Al,Ti) deformed in the temperature regime between –196 °C and 800 °C

1. Introduction

2. Experimental procedure

3. Results and discussion

Acknowledgments

References

Chapter 23. Dynamic recovery of the microstructure of screw dislocations in high purity b.c.c. metals

1. Introduction

2. Experimental procedure

3. Results

4. Discussion

5. Conclusion

Acknowledgments

References

Chapter 24. Heterogeneous dislocation loop nucleation and free surface effects on plastic deformation: an in situ transmission electron microscopy study

1. Introduction

2. Experimental procedure

3. Results and discussion

4. Conclusions

Acknowledgment

References

Chapter 25. Effect of precipitation on the development of dislocation substructure in low carbon steels during cold deformation

1. Introduction

2. Experimental details

3. Results

4. Discussion

5. Conclusions

References

Chapter 26. Transformation of dislocation patterns in fatigued copper single crystals

1. Introduction

2. Experimental procedure

3. Results and discussion

Acknowledgments

References

Chapter 27. Dislocation activity and differences between tensile and compressive creep of yttria doped alumina

1. Introduction

2. Macroscopic behavior

3. Microscopic analyses

4. Discussion

5. Conclusion

References

Chapter 28. High temperature deformation behavior of an Al-Fe-V-Si alloy

1. Introduction

2. Experimental procedure

3. Results

4. Discussion

5. Conclusions

Acknowledgments

References

Chapter 29. Dislocation-associated elastic energy storage in mechanical deformations

1. Introduction

2. Hysteresis behaviour in a quantitative manner

3. Case study on Cu single crystals

4. Fatigue-related implications

5. Conclusions

References

Chapter 30. Dislocation structure and corduroy contrast in a 316L alloy fatigued at (0.3–0.5) Tm

1. Introduction

2. Experimental procedure

3. Results

4. Discussion and conclusions

References

Chapter 31. On sequences of stable and unstable regions of flow along stress–strain curves of solid solutions—experiments on Cu–Mn polycrystals

1. Introduction

2. Experimental details

3. Results

4. Discussion

Acknowledgments

References

Chapter 32. Plastic deformation of single glide oriented Cu-2 to 15at.%Al crystals at elevated temperatures

1. Introduction

2. Results and discussion

3. Conclusions

Acknowledgments

References

Chapter 33. Onset mechanisms of discontinuous flow at low temperatures in one and two-phase Cu-Be alloys

1. Introduction

2. Theory

3. Experimental details

4. Results

Acknowledgments

References

Chapter 34. Hardening and softening in Zr-Sn polycrystals

1. Introduction

2. Experimental procedure

3. Experimental results and discussion

4. Conclusions

References

Chapter 35. Low-temperature abrupt deformation processes in metals: kinetic and statistical properties observed by means of electronic response

1. Introduction

2. Electronic response on plastic deformation

3. Kinetics and statistics of deformation processes

References

Chapter 36. Rheological behaviour of mild steel under monotonie loading conditions and cross-loading

1. Introduction

2. Experiments

3. Results

4. Discussion

5. Conclusions

References

Chapter 37. The Portevin-Le Châtelier effect in Al–2.92%Mg–.38%Mn alloy and linear location of acoustic emission

1. Introduction

2. Experimental procedure

3. Experimental results

4. Discussion

5. Conclusions

Acknowledgments

References

Chapter 38. Stress corrosion microcleavage in a ductile f.c.c. alloy

1. Introduction

2. Corrosion, crack tip and dislocation pile-ups

3. Results

4. Conclusion

References

Chapter 39. Dislocation-controlled stable crack growth in Mo and MgO

1. Introduction

2. Stable crack growth in iron-silicon

3. Experimental work

4. Dislocation modelling

5. Conclusions

References

Chapter 40. Low-energy dislocations and ductility of ferritic steels

1. Introduction

2. Experimental procedure

3. Results and discussion

Acknowledgment

References

Chapter 41. The peak of flow stress in the L12 structure and the elimination of Kear-Wilsdorf locks

1. Introduction

2. The properties of Kear–Wilsdorf barriers

3. Determination of saturation stresses

4. Comparison with experiments and conclusion

Acknowledgments

References

Chapter 42. Calculation of cross-slip parameters in f.c.c. crystals

1. Introduction

2. Our method of calculation

3. Results

4. Discussion

Acknowledgment

References

Chapter 43. Modelling high temperature creep of academic and industrial materials using the composite model

1. Introduction

2. Modelling the steady state and transient creep behaviour of pure aluminium

3. Modelling subgrain hardening in NiCr22Co12Mo

4. Modelling strain softening in X 20 CrMoV 12 1

5. Conclusions

Acknowledgments

References

Chapter 44. Dynamical model of the wall structure in persistent slip bands of fatigued metals I. Dynamical model of edge dislocation walls

1. Introduction

2. The dislocation model

3. Interacting edge dislocation currents in PSBs

4. The stationary solution

5. Distribution of the dipole heights

6. Moving dislocation walls

7. Concluding remarks

Acknowledgment

References

Chapter 45. Investigation of the formation of dislocation cell structures and the strain hardening of metals by computer simulation

1. Introduction

2. Development of cell structure and its characterization

3. Strain hardening and dislocation structure

4. Conclusions

References

Chapter 46. Role of the secondary slip system in a computer simulation model of the plastic behaviour of single crystals

1. Introduction

2. Basic assumptions of the model

3. Results

4. Conclusions

Acknowledgments

References

Chapter 47. Low-temperature dislocation internal friction in crystals

1. Introduction

2. Theory

3. Experimental results and discussion

4. Conclusions

References

Chapter 48. Ultrasonic study of the interaction potential between a dislocation and asingle solute atom

1. Introduction

2. Principle of the measurement

3. Experiment

4. Analysis

5. Applications

References

Chapter 49. Effects of magnetic fields on the dislocation unlocking fromparamagnetic centers in non-magnetic crystals

1. Introduction

2. Experimental details

3. Experimental results

4. Discussion

References

Chapter 50. A dislocation model for internal damping due to the thermal expansion mismatch between matrix and particles in microheterogeneous materials

1. Introduction

2. Experimental procedure

3. Experimental results

4. Modelling and discussion

5. Conclusion

Acknowledgments

References

Chapter 51. Interaction between dislocations and precipitates in an Al-Li alloy

1. Introduction

2. Experimental details

3. General observations

4. Evaluation of parameters of interaction between dislocations and precipitates

5. Conclusions for the model of the interaction between dislocations and precipitates

6. Dislocation multiplication and the planarity of slip

7. Discussion

8. Conclusions

Acknowledgments

References

Chapter 52. Comparison between simulation calculations and measurements concerning athermal yielding of precipitation hardening of Cu-Co single crystals

1. Introduction

2. Experimental results

3. Simulation calculation of critical shear stresses

4. Dissociation of dislocations

Acknowledgment

References

Chapter 53. Dislocation-point defects interaction in semiconductors and kink mobility

1. Introduction

2. Experimental details

3. Results and discussion

References

Chapter 54. Softening of á-iron by solute nitrogen atoms investigated between 30 and 300 K by use of stress-relaxation measurements

1. Introduction

2. Experimental details

3. Evaluation of measurements

4. Experimental results

5. Analysis and discussion

References

Chapter 55. Mechanisms of dislocation motion and multiplication in ionic and semiconductor crystals

1. Introduction

2. Experimental details

3. Results

4. Discussion

5. Summary

Acknowledgments

References

Chapter 56. Dislocation substructures in plastically deformed A1N

1. Introduction

2. Experimental details

3. Results

4. Discussion

References

Chapter 57. The influence of Peierls relief on low-temperature plasticity of CdTe single crystals

1. Introduction

2. Experimental details

3. Experimental results, analysis and discussion

References

Chapter 58. A new internal friction peak and the problem of the Peierls potential in f.c.c. metals

1. Introduction

2. Features of a new internal friction peak inaluminum

3. The picture obtained from the new peak

References

Chapter 59. A method for simulating electron microscope dislocation images

1. Introduction

2. Theory

3. Simulations

4. Results and discussion

5. Conclusion

Acknowledgments

References

Chapter 60. On the relationship between unusual mechanical properties and deformation substructures in ordered Ni3Al

1. Introduction

2. Experimental details

3. Results

4. Discussion

5. Conclusions

Acknowledgments

References

Chapter 61. A weak beam study of the dislocation structure in directionally solidified Ni3Al during deformation

1. Introduction

2. Experimental procedures

3. Results

4. Discussion

5. Conclusions

Acknowledgment

References

Chapter 62. Dislocation core structures in the ordered intermetallic alloy TiAl

1. Introduction

2. Experimental procedures

3. Results and discussion

4. Summary and conclusions

Acknowledgments

References

Chapter 63. Observations of dislocations relevant to the anomalous yield stress in Ll2 alloys

1. Introduction

2. Superkink statistics

3. Superkink structure

4. Anti-phase boundary tubes

5. Conclusions

Acknowledgments

References

Chapter 64. Transmission electron microscope in situ deformation of MC2 superalloy at room temperature

1. Introduction

2. Experimental details

3. Results

4. Discussion

5. Conclusion

References

Chapter 65. Substructure of dislocations in the ( 111 ) plane in Ni3Ga single crystals

1. Introduction

2. Experimental details

3. Results

4. Discussion

References

Chapter 66. The stress fields of edge dislocations near wedge-shaped boundaries and bonded wedges

1. Introduction

2. Method of calculation

3. Numerical results and discussion

4. Summary

Acknowledgments

References

Chapter 67. Interactions between lattice dislocations and grain boundaries in Ll2 ordered compounds investigated by in situ transmission electron microscopy and computer modelling experiments

1. Introduction

2. Experiments

3. Results

4. Discussion and conclusions

References

Chapter 68. Arrangement of misfit dislocations at Ti3Al/TiAl phase boundaries

1. Introduction

2. Mechanical properties

3. Microstructure

4. Model for the misfit dislocations

5. Discussion

6. Conclusions

References

Chapter 69. Image forces on dislocations: the elastic modulus effect

1. Introduction

2. The physical situation

3. Results

4. Conclusion

Acknowledgments

References

Chapter 70. Misfit dislocations and other defects in thin films

1. Introduction

2. The method of virtual defects (MVD)

3. Defects in one-phase films

4. Thin films on semi-infinite substrates

5. Dislocations in two-phase films

6. Conclusions

References

Chapter 71. Twin propagation in TiAl

1. Introduction

2. Experimental procedure

3. Experimental results

4. Discussion

5. Conclusions

Acknowledgments

References

Chapter 72. Changes in stacking fault sequences during the martensitic phase transformation in Cu-Zn-Al shape memory alloys

1. Introduction

2. Experimental details

3. Results

4. Discussion

5. Conclusions

References

Chapter 73. Twins and properties of classical and high- Tc superconductors

1. Introduction

2. Experimental details

3. Results

4. Conclusion

Acknowledgments

References

Author Index of Volume 164

Subject Index of Volume 164