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Analysis of the Impact of Biomateriał and the Technology of Prosthetic Crowns Manufacturing on The Connection with Veneering Ceramics

Ryniewicz Anna M., Ryniewicz Andrzej, Bojko Łukasz, Ryniewicz Wojciech

Tribologia

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2020

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nr 5

17--25

EN

The aim of the study is to identify the endurance parameters of prosthetic crowns veneered with dedicated ceramics on metal, glass-ceramic, and ceramic frameworks. Metal frameworks were made using CAD/CAM milling technology and SLM technology, while the glass-ceramic and ceramic frameworks were produced using only the CAD/CAM milling technology. The research materials are samples replicating the layered structures of prosthetic crowns. The veneering procedure must ensure the adhesion of the ceramics to the loadbearing framework. The tests modelling the conditions of concentrated loads during chewing were carried out using the Instron 3345 testing machine. Determination of microhardness in cross-sections through layered structures of crowns was performed using the HMV Micro Hardness Tester. The comparison of force loading the indenter as a function of penetration depth indicates that the value of the maximum depth depends on the configuration of microhardness of the framework and dentine. The zirconium ceramics ZrO2 (3Y-TZP) – veneered with Elephant Sakura silica ceramics – should be indicated as the most advantageous material composition.

PL

Celem pracy jest identyfikacja parametrów wytrzymałościowych koron protetycznych licowanych dedykowanymi ceramikami na podbudowach metalowych, szklanoceramicznych i ceramicznych. Podbudowy metalowe zostały wytworzone w technologii frezowania CAD/CAM i w technologii SLM, a podbudowy szklanoceramiczne i ceramiczne w technologii frezowania CAD/CAM. Materiałem badań są próbki replikujące warstwowe struktury koron protetycznych. W wyniku procedury licowania musi być zapewniona adhezjaceramiki do podbudowy nośnej. Badania modelujące warunki skoncentrowanych obciążeń podczas żucia wykonano na maszynie wytrzymałościowej Instron 3345. Wyznaczenie mikrotwardości w przekrojach przez warstwowe struktury koron zrealizowano na maszynie HMV Micro Hardness Tester. Zestawienie siły obciążającej wgłębnik w funkcji głębokości penetracji wskazuje, że wartość maksymalnego zagłębienia, zależy od konfiguracji mikrotwardości podbudowy i mikrotwardości dentyny. Jako najkorzystniejszą kompozycję materiałową należałoby wskazać ceramikę cyrkonową ZrO2 (3Y – TZP) – licowaną ceramiką krzemionkową Elephant Sakura.

2

Fatigue failure analysis of three-layer Zr–Ti/Zr–Steel composite plates: an insight into the evolution of cracks initiated at the interfaces

Karolczuk Aleksander, Carpinteri Andrea, Robak Grzegorz, Derda Szymon, Prażmowski Mariusz

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 4

604--616

EN

Initiation and evolution of fatigue cracks at the interfaces in three-layer Zr–Ti/Zr–Steel composites is herein examined by in situ optical microscopy for the first time. Specimens cut out from three composite plates comprising Zr 700, Ti Gr. 1, and P265GH steel layers have been subjected to uniaxial fatigue cyclic loading. It is found that mechanical property mismatch between layers and defects at the interfaces can reduce the fatigue life of composite plates. An insight into the evolution of cracks initiated at the interfaces reveals that (1) most of the cracks grow into adjacent layers along two distinct planes, and (2) these cracks could lead to the fatigue failure of composites. One of these planes coincides with the adiabatic shear band orientation found in Ti Gr. 1 and Zr 700 layers. The interfaces in multilayer metallic composite could have excellent fatigue strength depending on their structural properties.

3

Composite sandwich footbridge – numerical ESL FEM calculations vs. In situ measurements

Miśkiewicz M., Chróścielewski J., Sobczyk B., Pyrzowski Ł.

Engineering Transactions

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2017

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Vol. 65, iss. 1

77--82

EN

Selected results of the static analysis of composite sandwich footbridge with the corresponding in situ measured values are compared in the paper. The analysed bridge is a research object, which was built in 2015 and is currently located at the Gdańsk University of Technology campus. Since it is a novel structure, a proper definition of the bridge numerical model, allowing its safe design, is very important. Therefore, instead of some preliminary research, carried out on sandwich beams or the bridge segment, also the calculated structural properties of the full scale object should match the experimentally predicted response. This verification was required to obtain permission for the bridge exploitation, according to the government regulations.

4

Renovation and strengthening of wooden beams with CFRP bands including the rheological effects

Kula K., Socha T.

Civil and Environmental Engineering Reports

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2016

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No. 22(3)

93--102

EN

The paper presents a work analysis of wooden beams reinforced with glued composite bands from the top and resin inclusions, taking into account the rheology of materials. The paper presents numerical model of the multimaterial beam work including rheological phenomena described by linear equations of viscoelasticity. For the construction of this model one used MES SIMULIA ABAQUS environment in which were prepared its own procedures containing rheological models. The calculation results were compared with the literature data. One has done an analysis of the advisability of the use of CFRP reinforcements bands in terms of rheological phenomena.

PL

W referacie zaprezentowano analizę pracy drewnianych belek wzmocnionych wklejonymi od góry taśmami kompozytowymi i inkluzjami żywicznymi z uwzględnieniem reologii materiałów. Przedstawiono model numeryczny pracy belki wielomateriałowej obejmujący zjawiska reologiczne opisane równaniami liniowej lepkosprężystości. Zaproponowano pięcioparametrowy model reologiczny opisujacy zachowanie drewna i kleju. Do budowy modelu numerycznego wykorzystano środowisko MES SIMULIA ABAQUS, w którym przygotowano własne procedury zawierające model reologiczny, napisane w języku FORTRAN. Wyniki obliczeń porównano z danymi literaturowymi. Dokonano analizy celowości stosowania wzmocnień taśmami CFRP w aspekcie zjawisk reologicznych. Stwierdzono bardzo korzystny wpływ tego typu wzmocnienia na wartości reologicznych przyrostów ugięć, które są o wiele mniejsze w przypadku belek wzmocnionych w porównaniu do belek litych.

5

Application and evaluation of layered silicate–chitosan composites for site specific delivery of diclofenac

Kevadiya B. D., Rajkumar S., Bajaj H. C.

Biocybernetics and Biomedical Engineering

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2015

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Vol. 35, no. 2

120--127

EN

The present study focuses on the in situ intercalation of anionic drug (diclofenac sodium, DS) and cationic polymer, Chitosan (CS) in montmorillonite (MMT) for drug release applications. The prepared DS/CS-MMT composites were further compounded with alginate (AL) to form beads to modify release response in gastric juice. The DS/CS-MMT composites were characterized by UV spectroscopy, XRD, FT-IR, TGA and DSC. Antibacterial assay of drug loaded composites was investigated and in vitro cell viability assay results point out the drug encapsulated in clay plates are less toxic to the cell than pristine drug. The in vitro release experiments revealed that the DS was released from DS/CS-MMT/AL in a controlled and pH dependent manner.

6

Stress distribution in two-layered half-space with periodical structure caused by Hertz pressure

Kołodziejczyk W., Kulchytsky-Zhyhailo R.

Journal of Theoretical and Applied Mechanics

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2013

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Vol. 51 nr 3

741--750

EN

The paper presents analytical solutions for displacements and stresses in an elastic layered half-space with periodic structure in the case of an axi-symmetrical contact problem. The solutions are arrived at employing the Hankel transform. Finally, a comparison is made between the results obtained using the classical theory of elasticity and those obtained within the framework of the homogenized model with microlocal parameters.

7

Sensitwity analysis in a fatigue delamination problem of an elastic two-layer composite

Figiel Ł., Lauke B., Kamiński M.

Engineering Transactions

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2008

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Vol. 56, iss. 1

65-87

EN

Several parameters can affect the fatigue delamination growth in laminates - these in-clude e.g. constituent material properties and/or composite shape. Knowledge about effects of these parameters can lead to a better understanding of the fatigue delamination behaviour and can also pinpoint directions for optimum composite design. These effects can be elucidated by carrying out an appropriate sensithdty analysis. A FEM-based computational approach to sensitivity analysis is proposed in this work to study composite parameter effects in a fatigue delamination problem of an elastic two-layer composite. It is used to calculate and analyse sen-sitivity gradients of the fracture parameter and fatigue cycle number with respect to composite design parameters such as layer elastic constants. It is observed that sensitivities computed from this approach are generally numerically stable. Obtained sensitivities pinpoint ąuantita-tively the most and least important composite parameters that govern a fatigue delamination process. Sensitivity results are verified by another computational approach and a very good agreement is found.

8

On the matrix techniques for modeling of thermoelastic waves in layered structures

Verma K. L.

International Journal of Applied Mechanics and Engineering

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2006

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Vol. 11, no 3

655-669

EN

The development of a general purpose model for thermoelastic wave propagation in Cartesian system for heat conducting isotropic layered plates is illustrated, the model can account for elastic and visco-elastic isotropic materials, single or multi-layered structures, and free or leaky systems. Theoretical treatment is presented for calculating the displacements, temperature, thermal stresses and temperature gradient within a multilayered plate in generalized theories of thermoelasticity, using the matrix transfer technique. Rigidly bonded and smooth interface condition is also considered as a special case to stimulate de-bonding of two materials layers. The model developed will be of value in material characterization and others quantitative information on thermo-mechanical, strength related properties of advanced materials. Relevant results of previous investigations and coupled thermoelasticity are deduced as special cases.

9

Optymalizacja kodu Monte Carlo do symulacji czasu przelotu fotonów w strukturach tkankowych

Żółek N. S., Liebert A., Maniewski R.

Bio-Algorithms and Med-Systems

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2005

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Vol. 1, no. 1/2

277--280

PL

Symulacje Monte Carlo są często wykorzystywane w modelowaniu transportu światła w strukturach optycznie mętnych. Pozwalają uzyskać dokładny opis rozchodzenia się światła, ale wymagają dużej mocy obliczeniowej. Najbardziej czasochłonnymi operacjami podczas symulacji są: obliczanie wartości funkcji logarytmicznej i trygonometrycznej oraz generowanie liczb pseudolosowych. W tym artykule została przedstawiona weryfikacja i porównanie metody Monte Carlo wykorzystującej aproksymację funkcji logarytmicznej i trygonometrycznej z metodą klasyczną (z dokładnym obliczaniem logarytmu i funkcji cosinus) i z rozwiązaniami równania dyfuzji dla struktur jednorodnych.

EN

Monte Carlo simulations are frequently used in modeling of light transport in turbid media. They allow precise description of light transport, but require long computation time. Logarithmic and trigonometric functions evaluation, and generation of pseudorandom numbers are main-time consuming procedures in Monte Carlo calculations of light transport. In this paper, parallel Monte Carlo method with approximated logarithmic and trigonometric functions is analyzed, verified, and compared to the original one (with exact computation of logarithm and cosine functions) and with solution of diffusion equation for homogeneous media.

10

Bi-continuum modelling of layered structures and crystalline interfaces

Sztyren M.

Journal of Technical Physics

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2002

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Vol. 43, no 3

265-276

EN

The bi-continuum model composed of two interpenetrating and dynamically coupled material continua is analysed as a simplified but relatively accurate way to describe some physical phenomena in crystalline solids. The essential novelty of our approach consists in treating a crystalline medium as a bi-continuum, even if the crystalline lattice is structurally single-component. Particular attention is paid to the oscillatory behaviour of solutions on the atomic level. Starting from a discrete atomic chain, the basic formulation of the bi-continuum model is derived. The essential features of the model, including accuracy of the results as functions of physical parameters, are discussed.

11

Application of hybrid stress FEM model in analysis of layered structures

Gołaś J.

Studia Geotechnica et Mechanica

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2001

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Vol. 23, nr 1-2

43--57

PL

Przedstawiono zastosowania programu numerycznego opracowanego przez GOŁASIA [9] do analiz statycznych grubych konstrukcji warstwowych pracujących w płaskim stanie odkształcenia. W algorytmach rozwiązań wykorzystano hybrydowy model naprężeniowy MES oparty na zmodyfikowanym funkcjonale wariacyjnym Reissnera [2], [3]. Analizowano stany przemieszczeń i naprężeń we wzmocnionym warstwowo podłożu pod fundamentem bezpośrednim oraz w tarczy zawierającej inkluzje.

EN

Applications of numerical program, developed by GOLAS [9] for the analysis of thick, layered structures in the state of pianę strain arę presented. In solution algorithms, advantage is taken of the hybrid stress FEM model based on the modified Reissner [2], [3] variational functional. Stress and displacement states arę analysed in subsoil under a slab foundation, layer-wise reinforced, and in a plate containing inclusions.

12

Reflection from layered dielectric structures with combined regular and random inhomogeneities

Guzev M.A., Popov G.V.

Journal of Telecommunications and Information Technology

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2000

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nr 1-2

80-82

EN

Optical wave reflection from a layered half-space with regular and random inhomogeneities where the regular perturbations correspond to a linear waveguide near the half-space boundary. Random inhomogeneities are simulated in the frame of the white noise model. The problem is solved analytically in a framework of the embedding method which reduces a boundary problem to the problem with initial values considering the field as a function of the half-space boundary coordinate and obtaining then its solution as a steady-state probability density of the reflection coefficient phase. Numerical calculations revealed some features of the field behaviour under the combined influence of regular and random inhomogeneities such as the reflection coefficient phase increasing inhomogeneity from uniform distribution for small regular inhomogeneities toward a strong peak at the phase equal to pi/2 for increasing ones, and some fine effects which are still greater then the calculation accuracy.