research

Load separation curves between self-affine rough surfaces have been studied by means of extensive numerical simulations. The results of the comparison with the two main contact mechanics theories have been reported. https://www.nature.com/articles/s41598-017-07234-4

Rong Long

Department of Mechanical Engineering, University of Colorado Boulder

Dear Colleagues,

  I thought some of you may be interested in our recent paper which has been accepted to Soft Matter.  The article is available online, here:

  http://pubs.rsc.org/en/content/articlepdf/2014/SM/C7SM01245D?page=search

   It contains a new model for the fracture of particulate rafts, and some new experimental results as well.  Questions are welcome. 

http://www.sciencedirect.com/science/article/pii/S0266353817310552

Effects of Cu, Mn, Al, Ti, Mo on generalized stacking fault energies, Rice-criterion ductilities, and twinabilities of CoCrFeNi-based face-centered cubic high entropy alloys were investigated using density functional theory calculations. The calculated barrier energies and twinnabilities revealed that the addition of Ti or Mo increased the tendency of dislocation glide and deformation twinning, while addition of Mn, Cu and relatively high amount of Al facilitated dislocation gliding and martensitic transformation. Low amount of Al resulted in only dislocation gliding.

Michele Ciavarella  Yang Xu Robert L. Jackson

Some Closed-Form Results for Adhesive Rough Contacts Near Complete Contact on Loading and Unloading in the Johnson, Kendall, and Roberts Regime

Journal of Tribology Copyright VC 2018 by ASME JANUARY 2018, Vol. 140 / 011402-1

Recently, generalizing the solution of the adhesiveless random rough contact proposed

by Xu, Jackson, and Marghitu (XJM model), the first author has obtained a model for

Phase-field models for crack propagation enable the simulation of complex crack patterns without complex and expensive tracking and remeshing as cracks grow. In the setting without inertia, the crack evolution is obtained from a variational energetic starting point, and leads to an equation for the order parameter coupled to elastostatics. Careful mathematical analysis has shown that this is consistent with the Griffith model for fracture. Recent efforts to include inertia in this formulation have replaced elastostatics by elastodynamics.

Dear colleagues,

Attached please find our new paper "Fatigue fracture of tough hydrogels" published on Extreme Mechanics Letters.

Fatigue fracture of tough hydrogels

Ruobing Bai, Quansan Yang, Jingda Tang, Xavier P. Morelle, Joost Vlassak, Zhigang Suo