the aim of present study is to investigate the kinematics of tool-workpiece’s relative movement in conventional and ultrasonic-vibration assisted turning (uat). the kinematic analysis of uat shows that the movement of cutting tool edge relative to the workpiece resulted from the cutting speed, feed speed and tool’s vibration affects the lateral machined surface of workepiece and leaves a repeat...

The Yoshida nonlinear isotropic/kinematic hardening material model is often selected in forming simulations where an accurate springback prediction is required. Many successful application cases in the industrial scale automotive components using advanced high strength steels (AHSS) have been reported to give better springback predictions. Several issues have been raised recently in the use of ...

Miniaturization of electronics to the nanoscale brings new challenges. Because of their small size and immense information and power processing capacity, large temperature gradients exist across nanoelectronics and power electronics solder joints. In this paper, a fully coupled thermomechanical-diffusion model is introduced to study the thermomigration induced strength degradation. A nonlinear ...

Abstract. The mechanical and damage behavior of a X100 steel after prestrain is studied in this work. Experimental results show both a plastic and rupture anisotropy: the T direction exhibits a higher ultimate stress but the lowest ductility and toughness. Prestrain reduces ductility and crack growth resistance. A model able to represent the plastic and damage behaviour of the material before a...

A constitutive theory for orthotropic materials is briefly summarized. The constitutive theory allows for anisotropy of the elastic response and anisotropy resulting from both the yield function and the kinematic hardening. The formulation also includes a constitutive theory, thermodynamically consistent, for the plastic spin and the re-orientation of the anisotropy properties towards a more fa...

The quasi-static evolution of an elastoplastic body with a multi-surface constitutive law of linear kinematic hardening type allows the modeling of curved stress-strain relations. It generalises classical small-strain elastoplasticity from one to various plastic phases. Firstly, we briefly recall a mathematical model represented by an initial-boundary value problem in the form a variational ine...

This note deals with two-mechanism models (= 2M models). 2M models (or, generally, multimechanism models) are a useful tool for modelling of complex material behavior. They have been studied and applied for the last twenty years. This note is focused on the modelling of 2M models in continuum-mechanical framework mainly in the case of plastic behaviour. In particular, some classes of 2M models ...

The quasi-static viscoplastic resp. elastoplastic evolution problem with isotropic or kinematic hardening is considered with emphasis on optimal convergence and adapted mesh-refining in the spatial discretization. Within one time-step of an implicit time-discretization, the finite element method leads to a minimisation problem for non-smooth convex functions on discrete subspaces. For piecewise...