research

Abstract: A simple nonlocal field theory of peridynamic type is applied to model brittle fracture. The kinetic relation for the crack tip velocity given by Linear Elastic Fracture Mechanics (LEFM) is recovered directly from the nonlocal dynamics, this is seen both theoretically and in simulations. An explicit formula for the change of internal energy inside a neighborhood enclosing the crack tip is found for the nonlocal model and applied to LEFM.

Roughness-Induced Adhesion

Submitted by Antonio Papangelo on Fri, 09/04/2020 - 13:29

research

Adhesion and fracture; adhesion; contact mechanics; friction;

Usually, roughness destroys adhesion and this is one of the reasons why the "adhesion paradox", i.e. a "sticky Universe", is not real. However, at least with some special type of roughness, there is even the case of adhesion enhancement, as it was shown clearly by Guduru, who considered the contact between a sphere and a wavy axisymmetric single scale roughness, in the limit of short-range adhesion (JKR limit).

EML Webinar by Prof. Robert Ritchie on September 9, 2020: Damage-Tolerance in Engineering and Biological Materials

Submitted by Teng Li on Thu, 09/03/2020 - 23:40

research

EML

EML Webinar

EML Webinar on 9 September 2020 will be given by Prof. Rob Ritchie, University of California, Berkeley, Discussion leader: Nanshu Lu, University of Texas at Austin.

Title: Damage-Tolerance in Engineering and Biological Materials

Time: 7 am California, 10 am Boston, 3 pm London, 10 pm Beijing on 9 September 2020

The effect of local chemical ordering on Frank-Read source activation in a refractory multi-principal element alloy

Submitted by Shuozhi Xu on Thu, 09/03/2020 - 01:20

research

multi-principal element alloys

phase-field modeling

dislocation dynamics

https://doi.org/10.1016/j.ijplas.2020.102850

Abstract

Fracture in distortion gradient plasticity

Submitted by Emilio Martíne… on Tue, 09/01/2020 - 11:35

research

#Plasticity #fracture

Dear iMechanicians,

I hope that the following paper is of interest to you. We use for the first time Gurtin (2004) gradient plasticity theory to investigate crack tip mechanics, revealing the existence of an elastic core adjacent to the crack tip, resembling a dislocation-free zone. Also, we show that the combination of strain gradient hardening and dislocation blockage can rationalise brittle fracture in elastic-plastic material interfaces.