Sea ice contains flaws including frictional contacts. We aim to describe quantitatively the mechanics of those contacts, providing local physics for geophysical models. With a focus on the internal friction of ice, we review standard micro-mechanical models of friction. The solid’s deformation under normal load may be ductile or elastic. The shear failure of the contact may be by ductile flow, ...

The failure process ahead of a mode I crack advancing in a ductile thin metal plate or sheet produces plastic dissipation through a sequence of deformation steps that include necking well ahead of the crack tip and shear localization followed by a slant fracture in the necked region somewhat closer to the tip. The objective of this paper is to analyze this sequential process to characterize the...

As our title implies, we consider materials failure at the fundamental level of atomic bond breaking and motion. Using computational molecular dynamics, scalable parallel computers and visualization, we are studying the failure of notched solids under tension using in excess of 108 atoms. In rapid brittle fracture, two of the most intriguing features are the roughening of a crack’s surface with...

The gravitational deformation of volcanoes is largely controlled by ductile layers of substrata. Using numerical finite-element modelling we investigate the role of ductile layer thickness and viscosity on such deformation. To characterise Ž . Ž the deformation we introduce two dimensionless ratios; P volcano radiusrductile layer thickness and P viscosity of a b . ductile substratumrfailure str...

In assessments of the seismic adequacy of existing steel bridges, the steel-to-concrete anchorage connections typically found at the base of steel truss piers can be potentially vulnerable, having little to no ductility and inadequate strength to resist seismic demands. Many other non-ductile failure locations may also exist along the seismic load path. Failure would result in unacceptable perf...

Mechanical properties of alloys have a strong relation with microstructure and determination of their behavior can lead to multiple advantages. To obtain this goal, finite element method )FEM( is one of the best ways. In this study a series of experiments were carried out on the produced Ti-6Al-4V to obtain its mechanical characteristics and to prepare it for photographing in micro dimensions. ...

This paper reports ductile or partial ductile mode machining of silicon, glass and some advanced ceramics. Results are presented using scanning electron micrographs of the machined surfaces. Grinding and lapping operations using inexpensive machine tools could produce ductile streaks on surfaces of these brittle materials under good conditions. Manufacture of spherical glass lenses by the fract...

The deformation and failure behavior of an AM60 magnesium alloy was investigated using tensile test on circumferentially notched specimens with different notch radii. The strain and stress triaxiality corresponding to the failure point were evaluated using both analytical and finite element analyses. Combining with systematical observations of the fracture surfaces, it is concluded that deforma...