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Several methods have been proposed for numerical homogeniation of linear viscoelastic materials, mainly based on Laplace transform or on multilevel (FE^2) approaches. In this paper, we introduce a much simpler technique based on a discrete representation of the effective relaxation tensor related to the homogeneous medium, which can then be used to evaluate the constitutive law in the form of a convolution product. In practice, calculations on the RVE reduce to 3 transient simulations in 2D and 6  in 3D. More details in

The Department of Industrial Engineering at the University of Pittsburgh anticipates an opening for a postdoctoral associate starting January 2012. The position’s primary area of research will focus on mechanics of micro-scale deformation processes and characterizing the thermomechanics of deformation at micrometer length-scales. Applicants with a strong background in computational solid mechanics and crystal plasticity will be preferred. 

Interested Applicants are requested to Email their CV to:  ravishm [at] pitt [dot] edu 

Dear My friends:

‚Source truncation and exhaustion: Insights from quantitative in-situ
TEM tensile testing' by D. Kiener and A.M. Minor (http://dx.doi.org/10.1021/nl201890s).

We recently published two papers that present an optimization method to design multi-layer composites with damping properties. The method consists in adding elastomeric layers in the composite. In this way, a multi-criteria optimization tool has been developed to determine the best geometrical and material properties of the composite: position of the elastomeric layers, layers thickness, ...

Two new books:

M. Nosonovsky and P.K.Rohatgi Biomimetics in Materials Science:
Self-healing, self-lubricating, and self-cleaning materials (Springer
Series in Materials Science, Vol. 152, 2011, Hardcover, ISBN
978-1-4614-0925-0)

M. Nosonovsky and B. Bhushan (eds.), Green Tribology Biomimetics, Energy
Conservation, and Sustainability (Springer Series: Green Energy and
Technology, 2011, Hardcover, ISBN 978-3-642-23680-8 )

We develop a method of poroelastic relaxation indentation (PRI) to characterize thin layers of gels.  The solution to the time-dependent boundary-value problem is obtained in a remarkably simple form, so that the force-relaxation curve obtained by indenting a gel readily determines all the poroelastic constants of the gel—the shear modulus, Poisson’s ratio, and the effective diffusivity.  The method is demonstrated with a layer of polydimethylsiloxane immersed in heptane.