The existence of multi-axial states of stress cannot be avoided in elevated temperature components. It is essential to understand the associated ailure mechanisms and to predict the lifetime in practice. Although metal creep has been studied for about 100 years, many problems are still nsolved, in particular for those involving multi-axial stresses. In this work, a state-of-the-art review of cr...

The nucleation of microvoids from second phase particles in an AlMgSi alloy has been investigated. The work has comprised detailed stress analyses of elastic particles situated in an elastic-plastic matrix as well as damage mechanics analyses of the ductile fracture behaviour of smooth and notched axisymmetric tensile specimens. Based on the micromechanical analyses of isolated particles, gener...

Residual stresses are common in metal structures, essentially influencing their mechanical behaviour. We consider a combined experimental/theoretical approach to residual stresses. The theoretical basis of analysis is provided by the recently developed F0-approach, operating with explicit relation between load-free and stress-free configurations. titanium alloy Ti-6Al-4V modelled multiplicative...

The shear-transformation-zone (STZ) theory of plastic deformation in glass-forming materials is reformulated in light of recent progress in understanding the roles played by the effective disorder temperature and entropy flow in nonequilibrium situations. A distinction between fast and slow internal-state variables reduces the theory to just two coupled equations of motion, one describing the p...

Crack initiation and propagation is a common concern for molecular composites such as plastic bonded explosives (PBXs) and pharmaceutical tablets. Under compressive stresses, cracks form at contacts between crystals and propagate along crystal-binder interfaces, causing composite failure. To investigate this process, crystal-binder interfaces have been characterised and their mechanical propert...

Notch deformation behaviour under monotonic and cyclic loading conditions was investigated using circumferentially notched round bar and double-notched flat plate geometries, each with two different notch concentration factors. Notch strains for the double-notched plate geometry were measured with the use of miniature strain gauges bonded to specimens made of a vanadium-based microalloyed steel...

Silicon can host a large amount of lithium, making it a promising electrode for high-capacity lithium-ion batteries. Recent experiments indicate that silicon experiences large plastic deformation upon Li absorption, which can significantly decrease the stresses induced by lithiation and thus mitigate fracture failure of electrodes. These issues become especially relevant in nanostructured elect...

The theory of plasticity is the branch of mechanics that deals with the calculation of stresses and strains in a body, made of ductile material, permanently deformed by a set of applied forces. The theory is based on certain experimental observations on the macroscopic behavior of metals in uniform states of combined stresses. The observed results are then idealized into a mathematical formulat...

On microscopic and mesoscopic scales, plastic flow of crystals is characterized by large intrinsic fluctuations. Deformation by crystallographic slip occurs in a sequence of intermittent bursts (’slip avalanches’) with power-law size distribution. In the spatial domain, these avalanches produce characteristic deformation patterns in the form of slip lines and slip bands which exhibit longrange ...

In this paper, FEM modeling and simulation of orthogonal cutting of AISI 1045 steel is studied by using dynamics explicit Arbirary Lagrangian Eulerian method. The simulation model utilizes the advantages offered by ALE method in simulating plastic flow around the round edge of the cutting tool and eliminates the need for chip separation criteria. JohnsonCook work material model is used for elas...