This work reports for the first time the effect of femtosecond laser shock peening (fLSP) without a sacrificial overlay under atmospheric conditions (no confinement) on the corrosion behaviour of AA2024-T3. After fLSP and additional exposure to air a superhydrophobic state (   ± 4°) is achieved. Moreover, fLSPed corrosion-resistant surface contributes to increased polarization resistance, reduced corrosion current and lower anodic dissolution, with long-term stability in aggressive chloride solution. Furthermore, SEM/EDS /2/ characterisation reveals reduction in pitting and complete eradication of intergranular corrosion (IGC) attack due to reduced metal/electrolyte contact area and homogeneous, refined microstructure which prevents chain-link IGC propagation.

Effects of test specimen geometry on creep behaviour of 12Cr steel in miniaturised disc bend tests B. Ule, R. S Ï turm and V. Leskovs Ï ekThe results of miniaturised disc bend creep tests carried out on at and on preformed sombrero shaped disc test specimens made of high alloy 12Cr steel have shown that the time to rupture is practically the same for both kinds of test specimen. It was therefore proven that the initial, large and rapid hot plastic deformation of at disc test specimens does not effect the regularity of the creep process in such tests. Miniaturised disc bend creep tests carried out on at disc test specimens of slightly different thickness con rmed the general validity of the modi ed Mukherjee -Bird -Dorn power law relation for time to rupture with thickness of the disc as the equation parameter. However, the thickness of the disc should be smaller or at most equal to the actual die clearance of the disc bend creep testing equipment.MST/5721

This paper proposes the study and implementation of a sensor with a metamaterial (MM) lens in electromagnetic nondestructive evaluation (eNDE). Thus, the use of a new type of MM, named Conical Swiss Rolls (CSR) has been proposed. These structures can serve as electromagnetic flux concentrators in the radiofrequency range. As a direct application, plates of composite materials with carbon fibers woven as reinforcement and polyphenylene sulphide as matrix with delaminations due to low energy impacts were examined. The evaluation method is based on the appearance of evanescent modes in the space between carbon fibers when the sample is excited with a transversal magnetic along z axis (TMz) polarized electromagnetic field. The MM lens allows the transmission and intensification of evanescent waves. The characteristics of carbon fibers woven structure became visible and delaminations are clearly emphasized. The flaws can be localized with spatial resolution better than λ/2000.

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Figure 1: Simulation results of a presbyopic eye (i.e., limited accommodation) using a progressive addition lens (B-spline/sphere): view through the far vision section (left) and near vision section (right). Defocus is computed approximately and rendertime is less than 32 ms per frame. The smaller images show effective astigmatism and refractive power of wavefronts at the virtual eye lens, respectively. AbstractWe present a novel approach that allows real-time simulation of human vision through eyeglasses. Our system supports glasses that are composed of a combination of spheric, toric and in particular of free-form surfaces. In order to obtain eye accommodation we perform wavefront tracing on the GPU. Defocus is achieved either by progressive distributed ray tracing of the eye lens (accurate) or by approximate blurring according to the obtained wavefront parameters. While the first variant is best suited guiding lens manufacturers during the design process of lenses, we consider the second approach ideal for giving customers a real-time impression of customized virtual spectacles in eye shops. Additionally, we visualize refractive power and effective astigmatism of incident wavefronts. That allows quality assessment of special purpose lenses such as reading or sport glasses in particular scene environments.

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