Die im thermischen Vorspannprozess induzierten Eigenspannungen verursachen unter polarisiertem Licht Anisotropie-Effekte Glas. Derzeit beschränkt sich die Kontrolle dieser Anisotropien, welche als optische Gangunterschiede quantifiziert werden, auf Einzelgläser. In Studie werden erstmals spannungsoptische Untersuchungen an Verbundgläsern durchgeführt. Im Zugversuch wird Konstante von PVB und SG...

Abstract The surfaces of many planetary bodies, including asteroids and small moons, are covered with dust to pebble-sized regolith held weakly the surface by gravity contact forces. Understanding reaction an external perturbation will allow for instruments, sensors anchoring mechanisms use on such surfaces, implement optimized design principles. We analyze behavior a flexible probe inserted in...

The objective of this research was to evaluate the passivity by measuring the passive fit and strain development of frameworks screwed on abutments, made by CAD/CAM technology, and to compare these parts with samples manufactured by conventional casting. Using CAD/CAM technology, four samples were made from zirconia (Zircad) and four samples were manufactured from cobalt-chrome (CoCrcad). The c...

Silorane-based composite, an epoxy material, was marketed as promising less polymerization contraction than conventional restorative materials. The aim of this study was to evaluate, by means of photoelasticity, the polymerization stress generated by a silorane-based composite. Thirty photoelastic rings with orifices measuring 5 mm (d) × 3 mm (h) were prepared and divided into 6 groups (n = 5) ...

Large scale simulations using cohesive zone interfacial elements were used to understand features such as penetration and deflection of crack during the process of interaction of mode-I crack with inclined interfaces. To perform these simulations, two set of inputs are necessary. The first one is to provide valid loading boundary conditions and the second one is to incorporate accurate cohesive...

Acoustic lenses are employed in a variety of applications, from biomedical imaging and surgery to defense systems and damage detection in materials. Focused acoustic signals, for example, enable ultrasonic transducers to image the interior of the human body. Currently however the performance of acoustic devices is limited by their linear operational envelope, which implies relatively inaccurate...

A systematic experimental investigation of the generation and subsequent evolution of impact damage in heterogeneous two-layer materials is presented. Model layered specimens involving a compliant polymer layer bonded with a metal layer were designed and subjected to impact loading to simulate failure mechanisms in real time. High-speed photography and dynamic photoelasticity were utilized to v...

In this paper, a novel tactile photoelastic transducer for normal forces is presented. When a normal input force profile is applied to the transduction medium, stress is generated in the photoelastic layer making it birefringent. Consequently, circularly-polarized input light becomes elliptically polarized at the output due to the introduction of a phase-lead distribution. If a circular-reflect...

Fluid-solid coupling typically plays a negligible role in confined converging shocks in gases because of the rigidity of the surroundingmaterial and large acoustic impedance mismatch of wave propagation between it and the gas. However, this is not true for converging shocks in a liquid. In the latter case, the coupling can not be ignored and properties of the surrounding material have a direct ...

Lack of passivity has been associated with biomechanical problems in implant-supported prosthesis. The aim of this study was to evaluate the passivity of three techniques to fabricate an implant framework from a Co-Cr alloy by photoelasticity. The model was obtained from a steel die simulating an edentulous mandible with 4 external hexagon analog implants with a standard platform. On this model...