Abstract. This letter addresses the dependence of homogeneous dislocation nucleation on the crystallographic orientation of pure copper under uniaxial tension and compression.  Molecular dynamics simulation results with an embedded-atom method potential show that the stress required for homogeneous dislocation nucleation is highly dependent on the crystallographic orientation and the uniaxial loading conditions; certain orientations require a higher stress in compression (e.g., <110> and <111>) and other orientations require a higher stress in tension (<100>).  Furthermore, the resolved shear stress in the slip direction is unable to completely capture the dependence of homogeneous dislocation nucleation on crystal orientation and uniaxial loading conditions.

Might also be useful for simulating dislocation motion in a finite body.

Several sets of boundary integral equations for two dimensional elasticity are derived from Cauchy integral theorem.These equations reveal the relations between displacements and resultant forces, between displacements and tractions, and between the tangential derivatives of displacements and tractions on solid boundary.Special attention is given to the formulation that is based on tractions and the tangential derivatives of displacements on boundary, because its integral kernels have the weakest singularities.The formulation is further extended to include singular points, such as dislocations and line forces, in a finite body, so that the singular stress field can be directly obtained from solving the integral equations on the external boundary without involving the linear superposition technique often used in the literature. Body forces and thermal effect are subsequently included. The general framework of setting up a boundary value problem is discussed and continuity conditions at a non-singular corner are derived.  The general procedure in obtaining the elastic field around a circular hole is described, and the stress fields with first and second order singularities are obtained. Some other analytical solutions are also derived by using the formulation. 

Myfeeling is that what we're trying to find are elastic constants of a continuum structure whose response in several (ideally all) deformations is the same as that of the carbon nanotube subjected to the same boundary conditions as the continuum structure.  We (A. Sears and R. C. Batra, Macroscopic Properties of Carbon Nanotubes from Molecular-Mechanics Simulations, Physical Reviews B, 69, 235406, 2004) have simulated simple tension and torsional deformations of a SWNT and its equivalent continuum structure defined as the one whose strain energy density is the same as that of the SWNT.  For an isotropic structure, the thickness of the equivalent structure was found to be~0.21 and it depends upon the MM potential used.  This has been validated by performing bending, buckling and combined loading tests on the SWNT and the equivalent continuum structure.

Here is a link to a 1996 book by C.H. Wang on Fracture Mechanics from the DSTO Aeronautical and Maritime Research Laboratory in Melbourne.

http://www.dsto.defence.gov.au/publications/1880/DSTO-GD-0103.pdf

In this chapter of "Hankbook of Theoretical and Computational Nanotechnology", I will provide an overview of the progress made in the last decade on theoretical modeling and computer simulation of strain-mediated formation of nanostructures on surface, focusing on strain-induced self-assembly and self-organization of two-dimensional (2D) patterns and structures. As part of a handbook, the main objective of the chapter is not to provide an extensive literature review on the topic. Instead, I will try to provide a general introduction and overview of the basic concepts and physical models along with some relatively detailed discussion of mathematical derivations and technical treatments so that readers (especially graduate students) who are interested in this topic can use this chapter as a guide and reference to start their own modeling and simulation.

In the brief presentation attached, I am summarizing my lab's recent work in the field of adhesion and work-of-adhesion measurements, and hoping to see who else is working in the field.  Here is some intro to the topic (by no means, it is complete - maybe we can add some recent work to this list as discussions develop)

By Martijn Feron, Zhen Zhang and Zhigang Suo

The mobility of charge carriers in silicon can be significantly increased when silicon is subject to a field of strain.In a microelectronic device, however, the strain field may be intensified at a sharp feature, such as an edge or a corner, injecting dislocations into silicon and ultimately failing the device. The strain field at an edge is singular, and is often a linear superposition of two modes of different exponents. We characterize the relative contribution of the two modes by a mode angle, and determine the critical slip systems as the amplitude of the load increases. We calculate the critical residual stress in a thin-film stripe bonded on a silicon substrate.

J.R.BARBER: INTERMEDIATE MECHANICS OF MATERIALS

Many of you may know my book on Elasticity, but may not be aware that I also wrote an undergraduate book on Intermediate Mechanics of Materials (Published by McGraw-Hill - ISBN 0-07-232519-4). This picks up from the typical elementary Mechanics of Materials course and deals with the next range of topics such as energy methods, elastic-plastic bending, bending of axisymmetric cylindrical shells and axisymmetric thick-walled cylinders. A full Table of Contents and the Preface are given below.

If you are interested in nano-calorimetry or combinatorial analysis, you might also find the following paper interesting. It was published as part of the MRS spring ‘06 meeting proceedings (http://www.mrs.org/s_mrs/sec_subscribe.asp?CID=6447&DID=175796&action=d…). This paper describes the parallel nano-differential scanning calorimeter (PnDSC), a new device for measuring the thermal properties of nano-scale material systems using a combinatorial approach.