research
Improved oxidation resistance of high emissivity coatings for reusable space systems
Here novel disilicides were explored for use in heat shields.
WSi2 and MoSi2 were applied as coatings on an insulating zirconia substrate.
The high emissivity of these compounds and their mixtures, makes them very attractive for use in spacecraft.
Compressive performance of MAX phase composites
Compressive performance and crack propagation in MAX phase composites
Here micro CT was used to reveal the structure performance relationships in metal/ceramic composites based on Ti2AlC / Al alloy combinations.
The results show the promise of infiltrated max phase materials in the production of high performance composites.
Theoretical insights into the hydrophobicity of low index CeO2 surfaces
Theoretical study into the hydrophobicity exhibited by a representative rare earth oxide, CeO2.
https://www.sciencedirect.com/science/article/pii/S0169433219302399
General correlations between local electronic structures and solute-defect interactions in bcc refractory metals
The interactions between solute atoms and crystalline defects such as vacancies, dislocations, and grain boundaries are essential in determining alloy properties. Here (Nature Communications, (2019) 10:4484) we present a general linear correlation between two descriptors of local electronic structures and the solute-defect interaction energies in binary alloys of body-centered-cubic (bcc) refractory metals (such as W and Ta) with transition-metal substitutional solutes.
Riemannian and Euclidean Material Structures in Anelasticty
In this paper we discuss the mechanics of anelastic bodies with respect to a Riemannian and a Euclidean geometric structure on the material manifold. These two structures provide two equivalent sets of governing equations that correspond to the geometrical and classical approaches to nonlinear anelasticity. This paper provides a parallelism between the two approaches and explains how to go from one to the other. We work in the setting of the multiplicative decomposition of deformation gradient seen as a non-holonomic change of frame in the material manifold.
The false myth of the rise in Italian self-citations, and the impressively positive effect of bibliometric evaluations on the increase of the impact of Italian research
Title: The false myth of the rise in self-citations, and the impressively positive effect of bibliometric evaluations on the increase of the impact of Italian research
Authors: Pietro D'Antuono and Michele Ciavarella
Categories: physics.soc-ph math.ST stat.TH Comments: 20 pages, 8 figures, 10 tables, in English and inItalian License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Journal Club for October 2019: A Metamaterial Approach to Soft Robotics
Metamaterials are rapidly emerging at the frontier of science and engineering. Mechanical metamaterials, in particular, have been designed to show superior mechanical properties, such as ultrahigh stiffness and strength-to-weight ratio, or unusual properties, such as a negative Poisson’s ratio and a negative coefficient of thermal expansion.
Wrinkling and smoothing of a soft shell
Transverse wrinkles usually occur in a uniaxially tensile elastic membrane and will be smoothed upon excess stretching. This instability-restabilization response (isola-center bifurcation) can originate from the nonlinear competition between stretching energy and bending energy. Here, we find a crucial factor, the curvature, which can control effectively and precisely the wrinkling and smoothing regimes. When the sheet is bent, the regime of wrinkling amplitude versus membrane elongation is narrowed, with local wrinkling instability coupled with global bending.