Alliages M Moire De Forme

Les alliages à mémoire de forme sont des matériaux uniques qui ont la propriété de se souvenir des traitements thermomécaniques subis (traction, torsion, flexion, etc.). Ils sont très utilisés dans l'industrie biomédicale, l'aéronautique ou le nucléaire. Cet ouvrage traite de leur compréhension physique et mécanique, et de leur utilisation, en se concentrant principalement sur la nature de la transformation martensitique, expliquée à travers les théorèmes de Ball et James. Les modèles macroscopiques à variables internes donnent les clés pour le calcul des structures en alliage à mémoire de forme, particulièrement utile pour l’utilisation industrielle de ces matériaux. Professeur à l’Ecole nationale supérieure de mécanique et des microtechniques de Besançon, Christian Lexcellent mène des recherches depuis plus de 20 ans sur les alliages à mémoire de forme. Ses enseignements portent sur le comportement linéaire et non-linéaire des matériaux.

L'auteur, spécialiste du comportement des matériaux solides et en particulier des alliages à mémoire de forme a cherché à trouver un lien avec la mémoire humaine. A cet effet, dans une approche interdisciplinaire, il fait ici un historique de la mémoire depuis les Grecs. Il a rencontré les sciences cognitives et en particulier les neurosciences qui ont réponse "à tout" concernant le fonctionnement du cerveau et donc de la mémoire. Heureusement, la lecture de La mémoire, l'histoire, l'oubli du philosophe Paul Ricoeur a permis d'équilibrer le propos. Cet ouvrage constitue un "voyage dans la mémoire" où l'on se rend compte que l'appréhension de la mémoire des métaux est plus simple que celle de la mémoire humaine.

This book investigates collisions occurring in the motion of solids, in the motion of fluids but also in the motion of pedestrians in crowds. The duration of these presented collisions is short compared to the whole duration of the motion: they are assumed instantaneous. The innovative concept demonstrated in this book is that a system made of two solids, is deformable because their relative position changes. The definition of the velocities of deformation of the system introduced in the classical developments of mechanics, the principle of the virtual work and the laws of thermodynamics, allows a large range of applications such as crowd motions, debris flow motions, and shape memory alloys motions. The set of the applications is even larger: social sciences and mechanics are unified to predict the motion of crowds with application to transport management and to evacuation of theaters management.

The book is mainly devoted to the thermomechanical behavior of materials during solid-solid phase transformations. The physical mechanisms including diffusion, martensitic transformation and plasticity are described from material science point of view. The global behaviour is deduced from methods of classical as well as irreversible thermodynamics and continuum and micro mechanics. Mainly metals, both non ferrous and ferrous alloys but also geological problems are dealt with. Special attention is given to transformation induced plasticity and shape memory alloys. Three chapters are concerned with practical applications (heat treatment, smart structures, residual stresses).

This book consists of two chapters. The first chapter deals with the thermomechanical macroscopic theory describing the transformation and deformation behavior of shape memory alloys. The second chapter deals with the extensive and fundamental review of the experimental works which include crystallography, transformations and mechanical characteristics in Ti-Ni, Cu-base and ferrous shape memory alloys.

This book offers an essential introduction to the linear and non-linear behavior of solid materials, and to the concepts of deformation, displacement and stress, within the context of continuum mechanics and thermodynamics. To illustrate the fundamental principles, the book starts with an overview of solid mechanics, experimental methods, classes of material behaviors, and the thermodynamic modeling framework. It then explores linear elastic behavior, thermoelasticity, plasticity, viscoplasticity, fracture mechanics and damage behavior. The last part of the book is devoted to conventional and magnetic shape memory alloys, which may be used as actuators or sensors in adaptive structures. Given its range of coverage, the book will be especially valuable for students of engineering courses in Mechanics. Further, it includes a wealth of examples and exercises, making it accessible to the widest possible audience.