Rheology, Physical and Mechanical Behavior of Materials 1 : Physical Mechanisms of Deformation and Dynamic Behavior

• Autore: Leroy Maurice
• Pubblicazione: Newark : , : John Wiley & Sons, Incorporated, , 2024; ©2023
• Edizione: 1st ed.
• Descrizione fisica: 1 online resource (345 pages)
• Nota di contenuto: Cover -- Title Page -- Copyright Page -- Contents -- Preface -- Chapter 1. Dynamic Plasticity: Dislocations -- 1.1. Introduction: how to describe plasticity? -- 1.1.1. Equivalence between forming processes and mechanical tests -- 1.1.2. Early stages of strain -- 1.1.3. Multiplication of dislocations -- 1.1.4. Fine-level observations (load.unload cycles) of the beginning of plasticization -- 1.2. Strain speed: ( for shearing) -- 1.2.1. A few definitions and orders of magnitude -- 1.2.2. Influence of the strain speed -- 1.2.3. The influence of the ghistoryh of strain -- 1.2.4. Dynamic.dynamic speed jump -- 1.3. The microstructural mechanisms of plasticity -- 1.3.1. Description of a dislocation and its line -- 1.3.2. Dislocation types -- 1.3.3. Crystallographic slips -- 1.3.4. Twinning -- 1.3.5. Force on the dislocation -- Chapter 2. Obstacles and Mechanisms of Crossings -- 2.1. Obstacles -- 2.2. Nature and resistance of obstacles -- 2.3. Example of measuring dislocation speeds -- 2.4. Microstructural mechanisms of the deformation rate -- 2.5. Mechanisms due to obstacles: hardening mechanisms -- 2.5.1. Obstacles to movement due to the dislocations themselves -- 2.5.2. Interactions with the forest -- 2.5.3. (Simplified) analysis of the consolidation due to the forest dislocation -- 2.5.4. Blockages of dislocations by pileups -- 2.5.5. Piling-up of dislocations -- 2.5.6. Influence of grain size -- 2.5.7. The case of nanomaterials (very small grain size): mechanical strength and hardness (T less than 0.3 Tf) -- 2.5.8. Influence of vacancies -- 2.5.9. Vacancies and dislocations -- 2.5.10. Stacking and twinning faults -- 2.5.11. Lomer.Cottrell barriers -- 2.5.12. Influence of obstacles associated with alloy elements and impurities -- 2.5.13. Anchoring dislocations -- 2.5.14. Formation of loops around particles. ; 2.5.15. Substitution and insertion of atoms -- 2.5.16. Evolution of the stress due to the added elements -- 2.5.17. Hardening by precipitates -- 2.6. Athermal mechanism of the movement of a dislocation -- 2.6.1. Density of dislocations and athermal stress -- 2.7. Thermally activated mechanism of the movement of a dislocation -- 2.7.1. Model of the behavior law -- 2.8. The viscous friction mechanism -- 2.8.1. Influence of viscosity of the medium on the viscous damping coefficient B -- Chapter 3. Dynamic Flows for Monocrystals and Polycrystals -- 3.1. Type of monocristal and polycrystal dynamic shear test samples (anisotropy and isotropy at high speeds) -- 3.2. The tensor of the shock stresses -- 3.3. Study of strain on a polycrystal -- 3.4. Dynamic flows by electromagnetic shocks, polycrystalline aluminum A5 -- 3.5. The case of six polycrystals -- 3.6. The case of monocrystals -- 3.6.1. Flow of a crystal -- 3.7. Models for CFCs -- 3.7.1. Viscoplastic dynamic flows of crystals: the case of aluminum ( ≃ 104 s-1) -- 3.8. Dynamics of flows shown using an ultra-fast camera -- 3.8.1. Dynamics of shear shocks -- 3.9. Viscoplasticity -- 3.9.1. Influence of phonic and electronic viscous friction: the case of lead -- 3.9.2. Viscoplasticity of metal crystals: influence of viscous friction -- 3.10. References for viscoplasticity -- Chapter 4. Limits to Static and Dynamic Formability -- 4.1. Plastic instability -- 4.1.1. Necking -- 4.1.2. Work hardening coefficient n -- 4.1.3. Instabilities studies (including speed effect ...) -- 4.1.4. Role of the strain speed -- 4.1.5. Summary -- 4.1.6. Generalized strain speed -- 4.2. Forming by pressing -- 4.2.1. Study of plastic instability -- influence of work hardening and anisotropy (characteristics of pressing thin sheets). ; 4.2.2. Parameters influencing instability: influences of the work hardening n and the anisotropy r -- 4.2.3. Pressing and formability in bending of sheets, shaping of elliptical bulbs -- 4.3. Damage: area between necking and fracture, the case between Forming Limit Curves (FLCs) and Fracture Forming Limit Curves (FFLCs) -- 4.3.1. Definition -- 4.3.2. Damage measurement D -- 4.3.3. Large strains and damage -- 4.3.4. Stress curve, strain of a 30 CD4 steel that has undergone a perlite globularization annealing (as given by Gathouffi (1984)) -- 4.4. Limit of the formability during necking (FLCs) and during fracture (FFLCs): influence of the strain rate -- 4.4.1. Types of strain -- 4.4.2. Comparison of FLC by : shock by electronic action in the case of aluminum alloys -- 4.4.3. Influence of strain rates on FLCs: static and dynamic formability -- 4.4.4. Metals studied -- 4.4.5. Strain trajectories: change of ε1 under ε2 -- comparison of low and high speeds -- 4.4.6. Comparison of the values for necking Z and fracture R -- 4.4.7. Change in necking -- 4.4.8. Change in fracture -- 4.4.9. Change between necking and fracture -- 4.4.10. Examples in magnetoforming and electro-hydroforming -- Chapter 5. Dynamic Resistance to Mechanical Shocks -- 5.1. Shock stresses -- 5.1.1. Energy aspects: momentum, kinetic energy, impulse -- 5.1.2. Comparison between stress levels in static and dynamic loads -- 5.2. Resilience test -- 5.2.1. Impact by a simple pendulum -- 5.2.2. Stress from polar shock impacts -- 5.2.3. Shock with rebound, coefficient of restitution, energy losses -- 5.2.4. Effect of resistance to movement, speed and stress upon impact -- 5.2.5. Resistant force proportional to the square of the instantaneous speed v2 -- 5.2.6. Elastoplastic resistance to impact and deformation of a solid -- 5.3. Typical loads, stress waves. ; 5.3.1. Longitudinal compression waves, mechanical impedance, stress -- 5.3.2. Wave step diagram -- 5.4. Dynamic tests, Hopkinson technique, laws of behavior -- 5.4.1. Principle of dynamic tests with Hopkinson bars -- 5.4.2. Measurement of strain by extensometry gauges -- 5.4.3. Data acquisition -- 5.4.4. Data processing: analysis of dynamic behavior tests of materials -- 5.4.5. Dynamic tension and torsion -- 5.4.6. Dynamic shear of monocrystals and polycrystals -- Appendix A. Primary Times of Mechanisms -- References -- Index -- EULA.
• Titolo autorizzato: Rheology, Physical and Mechanical Behavior of Materials 1
• ISBN: 1-394-25562-4; 1-394-25560-8
• Formato: Materiale a stampa
• Livello bibliografico: Monografia
• Lingua di pubblicazione: Inglese
• Record Nr.: 9910830288603321
• Lo trovi qui: Univ. Federico II