research

Dear friends: I am a PhD candidate studying fracture problems in tubes. I am doing J integral calculations in Abaqus, for tubes with through-wall circumferential cracks subjected to tensile and bending loads. I am using quadratic 20 nodes isoparametric elements with reduced integration (C3D20R), ranging from two to five elements through the wall thickness mesh.

Hello Everybody, this is my first post here.

Can anyone guide me in clearing this doubt? I would like to get the values of normalized flow stresses Vs Strain rate for 304 L stainless steel and Ti-6Al-4V. This values will be used as an input for simulating fan blade-out event. This values will be used since this process involves higher velocities, higher deformations and it occurs in less time.

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

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, ...