In armchair graphene sheets, crack propagates perpendicular to the applied strain, whereas crack propagation in zigzag sheets occurs at an angle to the straining direction. This occurs due to different bond structure along armchair and zigzag directions as shown in Fig. 1. Videos 1 and 2 show the fracture of armchair and zigzag sheets, respectively.
Fig. 1: Armchair and zigzag directions of graohene
The Department of Civil and Environmental Engineering at the National University of Singapore (NUS) is recruiting 2 post-doctorate research fellows to pursue research on ice-structure interaction in the Keppel-NUS Corporate Laboratory. As part of the S$75 million collaboration between Keppel Corporation and NUS, the team comprising of Prof. Andrew Palmer, Dr. Bai Wei, and Dr. Pang Sze Dai, seeks to develop solutions for offshore rigs to meet the challenges of harsh arctic environments in oil and gas exploration and production.
I have updated my notes on the Griffith paper. I added more description on the experimental determination of surface tension of solids. Griiffith himself determined the surface tension of glass by an experimental setup. Udin et al (1949) described a setup based on the same principle. This setup is now known as the zero creep experiment.
The class started today. I'll be teaching fracture mechanics this semester. I'll be mostly using the class notes I wrote in 2010, but will post updated ones.
In today's class I covered "Trouble with linear elastic theory of strength." I have just posted updated notes of the lecture. The new notes begin with the follwoing paragraphs.
Good mourning, i am using Abaqus software to inverstigate a crack propagation problem using Abaqus, in this regards i have created a seam crack iner the geometrie which is a plate under a plane stress condition, my problem is how to mesh around the crack tip in order to have a regular mesh around the crack tip so i can evaluate J integral for multiple contours, the Abaqus documentation mention the swept meshing technique but i coudn't find something about a 2D problem since the sweapt meshing technique nead to mesh a section and swept it over the rest of the body, and in 2d problem we
Applications are invited for few open positions in the area of
multiscale simulation of fatigue and fracture of advanced alloys and
nano-material based composites. Primary focus of this research is investigation
of fatigue and fracture behavior of nanomaterials and to develope various
constitutive models for continuum, based on large scale atomistic simulations.
Research effort will include development of analysis and design methods toward
improving material/structural behaviour using computer simulation. Interested
candidates should have preferably MTech/ME degree in
mechanical/civil/aerospace/material engineering discipline with good knowledge
there is a phd position on investigation of fracture mechanism of spot welds in automotive steels,
the funding is available for UK/EU nationals
please go to
http://www.shef.ac.uk/mecheng/phd/projects/deformation-spot-welding
for further information.
