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)
• Disciplina: 620.1123
• Soggetto topico: Rheology; Deformations (Mechanics)
• 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.
• Sommario/riassunto: This book, 'Rheology, Physical and Mechanical Behavior of Materials 1: Physical Mechanisms of Deformation and Dynamic Behavior' by Maurice Leroy, provides an in-depth analysis of the physical mechanisms underlying the deformation and dynamic behavior of materials. It explores the principles of dynamic plasticity, including dislocations, strain speeds, and microstructural mechanisms. The book also examines the challenges posed by obstacles in material deformation, such as hardening mechanisms and the influence of grain size and vacancies. Aimed at researchers and students in material science and engineering, this work seeks to enhance understanding of material behavior under various conditions.
• Titolo autorizzato: Rheology, Physical and Mechanical Behavior of Materials 1
• ISBN: 9781394255627; 1394255624; 9781394255603; 1394255608
• Formato: Materiale a stampa
• Livello bibliografico: Monografia
• Lingua di pubblicazione: Inglese
• Record Nr.: 9910876738603321
• Lo trovi qui: Univ. Federico II