Tires in service - especially in rough terrain - show a behavior which is well known as the cut and chip (CC) effect. This work describes unique analytical methods to characterize the fracture in rubber occurring during lab-simulated operation of the tire tread in rough terrain. The new test device controls and records multiple applied loads and displacements during cyclic impact to the surface of a solid rubber wheel to mimic and quantify the cut and chip damage experienced by tire tread compounds on off-road and poor road conditions. Characterization results are examined for carbon black filled compounds containing single polymers and binary blends of natural rubber, butadiene rubber, and styrene-butadiene rubber suitable for tire tread applications. The instrument provides a reliable method for evaluating the resistance of rubber against CC damage, and it can also be used in full contact mode for measurement of friction and wear.
Crack tip fields during cutting and tensile loading have been computed via finite element analysis, and measured using Digital Image Correlation during experiments executed on the Coesfeld Intrinsic Strength Analyser. The results show that cutting with a sharp blade while the specimen is under a small amount of tension produces a much-reduced dissipative process zone in front of the crack tip, in comparison with the process zone produced by tensile loading alone at nominally similar conditions. Because the energy released by a growing crack supplies both the process of breaking polymer chains to form crack faces, and the dissipative process at the crack tip, minimizing crack tip dissipation causes the observed remaining energy release rate during a cutting experiment to approach the limit reflecting the breakage of polymer chains. Conveniently, this implies that a relatively brief cutting experiment may be used as an indicator of long-term fatigue behavior.
Stoček, R., Mars, W. V., Kratina, O. , Machů, A., Drobilík, M., Kotula, O., Cmarová, A.:Characterization of ageing effect on the intrinsic strength of NR, BR and NR/BR blends.Constitutive Models for Rubber X - Proceedings of the 10th European Conference on Constitutive Models for Rubbers, ECCMR 2017, 2017, Pages 371-374.
Kratina, O., Stoček, R., Musil, B., Johlitz, M., Lion, A.:The study of fatigue behaviour of thermally aged rubber based on natural rubber and butadiene rubber.Constitutive Models for Rubber X - Proceedings of the 10th European Conference on Constitutive Models for Rubbers, ECCMR 2017, 2017, Pages 365-370, ISBN: 978-1-138-03001-5.
This work is focused on investigation of the influence of thermal aging on fatigue behavior of carbon black filled rubber compounds which have been based on Natural rubber (NR), Butadiene rubber (BR) and their blend with ratio 50/50. The thermal aging was performed in thermal chamber at varied temperatures 30, 70 and 110 °C for 720 hours. Firstly, the influence of thermal aging on mechanical behavior under quasi-static tensile test followed by dynamic mechanical analysis (DMA) has been investigated. The fatigue behavior un-der sinusoidal waveform loading conditions has quantitatively been analyzed by using of dynamic testing equipment Tear and Fatigue Analyzer. The aim of this work was to investigate the influence of thermal aging on the fatigue behavior of rubber based on varied rubber types to understand the relationship between the thermal degradative processes occurred in rubber matrix under thermal aging and fatigue life. From the exper-imental work it was concluded based on all used testing methods, that the presence of BR rubber enhance the resistance against thermal aging and thus could be used as an efficient component reducing the aging degrada-tion in rubber blend systems.
Stoček, R., Kipscholl, R.:Influence of test specimen thickness on the fatigue crack growth of rubber.Constitutive Models for Rubber X - Proceedings of the 10th European Conference on Constitutive Models for Rubbers, ECCMR 2017, 2017, Pages 347-350, ISBN: 978-1-138-03001-5.
The present paper aims its focus to perform a complex study of the influence of test specimen thickness on the fatigue crack growth of natural and synthetic rubber to enhance the circumstantiality of the measuring meth-odology. In this work the mini-pure shear test specimens (geometry ratio 1/10 “length/width”) of the varied thickness 0.5 and 1.5 mm by using of the Tear and Fatigue Analyzer have been studied. Two varied types of rubber compounds based on NR and SBR, filled with 50 phr of carbon black and current curatives have been investigated. Three double notched test specimens of each material and thickness have simultaneously been tested under the Gauss pulse loading condition at varied strains. As result, the higher slopes represented by the material parameters, m have been determined for the thinner samples independent on material type. As next the significantly lower deviations of FCG values for thinner samples independent on material have been observed. Thus it was concluded that the lower thickness of the sample represents a more critical loading case, whereas the experimental data can be determined more precisely.
Datta, S., Antoš, J., Stoček, R.:A novel algorithm: Tool to quantifying rubber blends from infrared spectrum.Constitutive Models for Rubber X - Proceedings of the 10th European Conference on Constitutive Models for Rubbers, ECCMR 2017, 2017, Pages 213-217, ISBN: 978-1-138-03001-5.
Infrared (IR) spectroscopy can be used to detect the polymers present in a blend, provided the unique charac-teristic peaks of the polymers are known. However, quantification of such a blend is not possible without modifying the spectrum because of vertical baseline shifting, attributed to various reasons. The present work deals with the explanation of a uniquely created algorithm for baseline creation on and subsequent subtraction from the originally obtained spectrum. Using the algorithm, a scientific baseline fit was achieved which carved the way to find the exact relative peak heights of the polymers constituting a blend. The logicallogistic ap-proach to frame the algorithm is the subject matter of the work. An introduction to using the algorithm for ex-perimental quantification of a binary rubber blend is also provided. Of course, it is a general approach and can be used with equal effectiveness for any other binary compositions.
Harea, E., Stoček, R., Machovský, M.:Study of friction and wear of thermoplastic vulcanizates: the correlation with abraded surfaces topologyProceedings at 6th International Conference on Fracture Fatigue and Wear, IOP Conf. Series: Journal of Physics: Conf. Series 843 (2017) 012070, doi :10.1088/1742-6596/843/1/012070http://iopscience.iop.org/article/10.1088/1742-6596/843/1/012070
The work was focused on the study of friction and wear properties of thermoplastic vulcanizates (TPV) based on polypropylene (PP), natural rubber (NR) and styrene butadiene rubber (SBR) compounds containing all common additives and curatives using ball-on-flat method. Pure materials and binary TPV blends of PP/NR, as well those of PP/SBR with the compositions 95/5, 75/25 and 50/50 (in weight %) were compounded and analysed. It is very well known that the coefficient of friction (COF), as well as wear values of pure thermoplastic matrix are significantly lower than those for pure rubber. Thus, it was found that the friction coefficient and wear of TPVs significantly increased in accordance with increased content of rubber material. Surprisingly, NR compared with SBR of similar concentrations in PP matrix, considerably affected wear of samples and the friction coefficient remained almost unaffected. Finally the topology of abraded surfaces were examined by using scanning electron microscopy (SEM) in order to understand the relationship between the COF, wear process and the composition of TPVs.
Stoček, R., Kipscholl, R.:Accelerated predicative testing of tire behaviourBook of proceedings, International Conference on polymeric Materials in automotive & 23rd Slovak Rubber Conference 2017, May 29th – 31th, 2017, Bratislava, Slovakia, pp. 111-112, ISBN 978-80-89841-04-2
In practice, tires are exposed to complex dynamic loading conditions caused due to car’s kinematic energy, profile of road surface as well as influence of ozone concentration, solar radiation, different temperature etc. These complex processes constitute the initiation of micro-cracks in tire, which is the fundamental fracture element of rubber-matrix responsible for tire tread wear, proceeding of fracture processes as well as of total tire failure. The tests and determination of tire failure respective fatigue lifetime of rubber matrix used for tire applications in the field are time and money consuming and thus the effective testing methods in laboratory condition is highly appreciated. The aim of this work is to introduce a methodology leading to accelerated prediction of rubber matrix fatigue lifetime.The complex methodology is fundamentally based on determination of a minimum energy requirement for the rupture of chains in a crack of rubber matrix, which is known as intrinsic cutting strength and energy necessary for crack growth under increasing dynamic loading conditions. Finally the correlation of the methodology used with the fatigue lifetime has been discussed.
Stoček, R., W.V. Mars, Kratina, O., Machů, A., Drobilík, M., Kotula, O., Cmarová, A.:The effect of carbon black loading on the intrinsic strength of rubber based on EPDMBook of proceedings, International Conference on polymeric Materials in automotive & 23rd Slovak Rubber Conference 2017, May 29th – 31th, 2017, Bratislava, Slovakia, pp. 68-71, ISBN 978-80-89841-04-2
Stoček, R., Kipscholl, R.:SMART PREDICATIVE METHODOLOGY FOR TESTING OF TIRE BEHAVIOUR IN LAB SCALEProceeding in conference Rubbercon 2017, MAY 23–25, 2017, Prague, pp. 83-91, ISBN 978-80-906662-0-7
In practice, tires are exposed to complex dynamic loading conditions caused due to car’s kinematic energy, profile of road surface as well as influence of ozone concentration, solar radiation, different temperature etc. These complex processes constitute the initiation of micro-cracks in tire, which is the fundamental fracture element of rubber-matrix responsible for tire tread wear, proceeding of fracture processes as well as of total tire failure. The tests and determination of tire failure respective fatigue lifetime of rubber matrix used for tire applications in the field are time and money consuming and thus the effective testing methods in laboratory condition is highly appreciated. The aim of this work is to introduce a methodology leading to accelerated prediction of rubber matrix fatigue lifetime. The complex methodology is fundamentally based on determination of a minimum energy requirement for the rupture of chains in a crack of rubber matrix, which is know as intrinsic cutting strength and energy necessary for crack growth under increasing dynamic loading conditions. Finally the correlation of the methodology used with the fatigue lifetime has been discussed.
Stoček,R., Meier, J., Kratina, O., Kipscholl, R.:Numerical parameter describing the resistance against chip&cut behaviour of rubberPresented at the conference Innovation in rubber products London, December 2016.
The work has its focus on analytical methods to characterize and quantify the failure mechanisms in rubber by simulating the tire tread behavior in hard terrain. Tires in service - especially in hard terrain - show a behavior which is well known as chip&cut (CC) effect. The methodology is based on the experimental determination of the fracture data with respect to real tire loading conditions by using a new lab testing equipment which is fully instrumented and works dynamically. Here pure rubber based natural rubber (NR) and butadiene rubber (BR) as well as binary rubber blends suitable for tire tread applications are examined. The exact mechanisms which are effecting the tire tread while in service as dynamic impacts, frictional sliding and abrasion caused by hard asperities are discussed. Further, the measured data is related with the surface and internal structures of the tested specimen by using computer tomography (CT). Concluding we introduce the numerically quantified properties of rubber blends describing their resistance against CC behavior.
Fatigue performance has many aspects and dependencies that may be measured, but the most basic question is whether or not a crack can grow. Crack growth can occur if enough energy is provided to cleave polymer chains that cross the crack plane, and it cannot occur otherwise, irrespective of how many cycles might be applied. We have developed an instrument -the Intrinsic Strength Tester - to measure this minimum energy requirement for crack growth. The instrument uses a highly sharpened blade to cut material under controlled conditions, while simultaneously measuring and recording all of the information needed to account fully for the energy balance on the crack.
Stoček, R.; Kratina, O.; Kipscholl, R.::FRACTURE BEHAVIOR OF TIRE TREAD (APLIKACE OF RECYCLED RUBBER)Proceedings of the Gumference 2015 in Zlín
Euchler, E.; Stoček, R.; Gehde, M.; Bunzel J.-M.; Saal, W.; Kipscholl, R.:FRACTURE BEHAVIOR OF RUBBER POWDER MODIFIED RUBBER BLENDS APPLIED FOR CONVEYING BELT TOP COVERS11th Fall Rubber Colloquium, Hannover, Germany, November 26-28th 2014
Abstract: The aim of this study is concentrated on the experimental investigation of wear resistance of rubber powder modified rubber blends. The modification of Styrene-Butadiene-Rubber (SBR) blends applied for conveying belt top covers has been modified by ground rubber (rubber powder) based on SBR. To simulate real wear behavior of conveying belt top cover rubbers charged with real loading conditions, we theoretically describe the rubber wear mechanism occurring in the field. An own developed testing equipment based on gravimetric determination of mass loss of rubber test specimen was used investigating dynamic wear with respect to fracture properties of conveyor belt top cover materials. Furthermore we investigated fatigue crack growth (FCG) data over a broad range of tearing energy characterized by Tear Analyzer. Thus, we demonstrate the influence of rubber powder on resistance against occurrence of fracture and dynamic wear as a function of the rubber powder content in rubber blends applied for conveying belt top covers.
Stoček, R.; Euchler, E.; Kipscholl, R.; Ghosh, P.:Influence of thermal aging process on the crack propagation of rubber used for tire treadProceeding in: Polymertec 2014, 25.-27.6.2014, Merseburg, Germany
Tire tread, transferring the car forces on the road, is fundamentally based on highly filled, cross-linked and topologically entangled rubber blends, which show an excellent damping behavior. Thus the tire tread commonly is exposed to high dynamic loading conditions, fur-thermore the tire tread is naturally influenced with physical processes caused due high tem-perature fluctuation, ozone concentration, solar radiation, influence of fluid medium, etc. These extreme requirements have a significant effect on the fatigue and failure tire tread behaviors, whereas these processes particularly lead to the degradation of the mechanical behavior of rubber matrix. The initiation of local instability in tire tread due to failure is par-ticularly caused by micro-crack initiation. Its propagation could have fatal consequences be-cause of the resulting global tire’s instability and thus high potential danger caused due to car accident. Hence the understanding of the crack initiations and its propagation in rubber regarding to the applied physical processes as well as loading conditions is a subject of high scientific interest. Its description will improve the safety, higher durability and life service of the tire as well. It is well known, that the mechanical and specially fracture behaviors depend on the struc-ture of rubber matrix. Particularly the characteristic behavior are based on the filler network build with the nanoparticles, size of filler cluster, interaction of filler-filler- and polymer-filler-bonds and the specific surface of filler under the identical compounding conditions [1, 2]. The effect of rubber reinforcement caused due to rubber modification with various fillers on crack or fatigue resistance has been studied in a lot of publications [1, 3, 4] and are well described. The naturally applied physical processes, which the tire tread is exposed, cause the aging of rubber matrix. The main importance has oxidative attack with simultaneously actuating thermal processes. The oxidative degradation of a sulphur cured rubber proceeds via at least one chain reaction sequence which introduces C-C and C-O-O-C crosslinks between polymer chains and another sets of chain reactions between oxygen and the sulphur atoms. If the thermal processes take an influence, it is necessary to balance the rate of reaction of oxygen with the elastomer and the rate of diffusion of the oxygen into the bulk material. If the tem-perature is relatively low, it has been evaluated that for cured rubber diffusion predomi-nates and therefore there is slow oxidation throughout the product. Contrariwise as the thermal activity rises, the rate of oxidation increases significantly than the rate of diffusion. Thus a substantial oxidation occurs on the surface at higher temperature and a brittle oxi-dized surface is formed. The critical stress of polymer chains in an oxidized rubber surface occurs in a lower strain compared to the not oxidized material, thus the mechanical proper-ties of rubber degrade. Generally the aging is interconnected to loss of mechanical properties over the whole life-time of the tire tread . The most efforts in this field of research were only investigated to the observation of crack propagation respectively rupture of rubber test specimens under quasi-static loading conditions with no relationship to the fatigue behavior of rubber matrix. Huang et al.  studied the phenomenon of cyclic ageing on Natural Rubber (NR). They found, that for NR, aging at lower temperatures leads to a decrease in modulus, while at higher temperatures it leads to an increase in modulus. Bauer et al.  studied the mechani-cal properties of skim tire based on Butadien Rubber (BR) under the oxidative aging with fill gases 50/50 blend of N2/O2 at various temperatures in the range from 50 to 70°C. They demonstrated the decreasing of elongation-to-break and increasing of modulus versus time of aging in the whole range of temperatures. This decreasing in mechanical behavior leads to high inclination of rubber material to the failure and proves the initiation of micro-cracks. The micro-cracks in tire tread caused due to natural physical aging are initiated at tire steady state because while rolling the stress states in tire under dynamic loading condition have a predominant influence on micro-crack initiation. The aim of this study is to determine the influence of thermal aging processes at common atmosphere in dependence on exposing time as well as the varied temperature directly in-fluencing the loaded rubber test specimen on fatigue crack growth (FCG) behavior under dynamic loading condition. In the present study, FCG behavior of Natural Rubber (NR) and Styrene-Butadiene Rubber (SBR) blends suitable for tire tread application has been investi-gated.
Kratina, O.; Euchler, E.; Stoček, R.; Čermák, R.:Relation between steady state and dynamic powdery wear: An application of powdery rubber wear theory of rubber modified with waste rubber powderProceeding at European Symphosium on Friction, Wear and Waer Protection, 2014, Karlsruhe, Germany
Steady state as well as dynamic rubber wear is characterized with separation of rubber particles from the rubber surface and this involves the crack propagation. The crack growth rate of rubber depends on the roughness of contact element, whereas the low rate is involved on not too sharp surfaces as in the case of an interaction between common road and tyres. On the other hand the high crack growth rate occurs in the case of surfaces with large asperities, e.g. hard terrain. In this study we apply a theory of powdery rubber wear to the experimental analysis of wear at steady state simulated the common road surface as well as dynamic chip and chunk conditions simulating the hard terrain for evaluation of particle size distribution released from rubber modified with different content of separated size of rubber powder particles made from waste truck tyres. Finally we show that the wear rate and particle size distribution strongly depends on type of loading condition. We consider the influence of rubber powder on rubber wear resistance and we demonstrate the relation between rubber wear rate and crack growth rate which correspond with the powdery rubber theory.
Euchler, E.; Kratina, O.; Stoček, R.; Gehde, M.:A study of correlation between crack initiation during dynamic weAr process and fatigue crack growth of reinforced rubber materialsProceeding at European Symphosium on Friction, Wear and Waer Protection, 2014, Karlsruhe, Germany
The aim of this study is concentrated on the experimental investigation of crack initiation during the dynamic wear of rubber-like materials, whereas the process is correlated with the Fatigue Crack Growth (FCG) behavior. Rubber blends based on Natural Rubber (NR) and Polybutadiene Rubber (BR) suitable for tyre tread application have been investigated. The dynamic wear behavior has been studied using an own developed testing equipment based on gravimetric determination of mass loss of test specimen and energy-input during the testing period. The fatigue crack growth analyses were performed under pulse loading condition using Tear Analyzer (TA) in accordance to loading behavior of rolled tyre. As specific results we show the crack initiation process during the dynamic wear with respect to different impact energy and correlate the liability to crack initiation with crack growth rate data at given tearing energy as a function of the rubber blend compositions. We demonstrate the higher crack initiation resistance of rubber blends with increased content of BR, while predominant influence of NR improves the resistance against crack propagation. We show the process of crack initiation during the dynamic wear significantly dependent on impact energy.
Stoček, R.; Musil, J.; Kolarik, R.;Kuřitka, I.:FUNDAMENTAL STUDY OF DEFORMATION BEHAVIOR OF FLUID FILLED ELASTIC CELLSPLASTKO 2014, 8. ─ 9. 4. 2014, ISBN 978-80-7454-335-7
The aim of this study is focused on experimental investigations of deformation behavior of fluid filled elastic cells, with respect to the different viscosities of fluids. The deformation behavior of cells of fundamental spherical geometries with respect to the defined quasi-static compression loading conditions has been demonstrated. The evaluated mechanical properties in the relation to the geometry of deformed cells obtained from the optical analysis performed simultaneously over the complete measurement have been studied.
Kratina, O.; Stoček, R.; Euchler, E.; Čermák, R.:Vliv přídavku gumového prachu na kvazistatické a dynamické lomové vlastnosti gumárenských směsíPLASTKO 2014, 8. ─ 9. 4. 2014, ISBN 978-80-7454-335-7
Pryž je díky svým jedinečným vlastnostem průmyslově hojně využívaný materiál. S její rostoucí spotřebou, rostou také objemy pryžového odpadu. Jedním z možných způsobů využití tohoto odpadu je jeho rozemletí na gumový prach a takto připravený prach opětovně použít jako plnivo do nově vznikajících gumárenských směsí. Cílem tohoto výzkumu bylo porovnat změny v kvazistatickém a dynamickém lomovém chování v závislosti na množství přídavku gumového prachu.
Stoček, R.; Kratina, O.; Kipscholl, R.:ADVANCED INDUSTRIAL METHODS FOR CHARACTERIZATION OF TIRE FAILUREPLASTKO 2014, 8. ─ 9. 4. 2014, ISBN 978-80-7454-335-7
In practice, tires are exposed to complex dynamic loading conditions caused due to car’s kinematic energy, profile of road surface as well as influence of ozone concentration, solar radiation, different temperature etc. These complex processes constitute the initiation of micro-cracks in tire, which is the fundamental fracture element of rubber-matrix responsible for tire tread wear, proceeding of fracture processes as well as of total tire failure. The tests and determination of tire failure in the real usage are time and money consuming and thus the effective testing method in laboratory condition is highly appreciated. This work focuses on the advanced industrial methods for experimental characterization and prediction of tire failure in the laboratory. Finally we introduce new trends in the characterization of tire failure in the laboratory based on the biaxial-dynamic loading conditions.
Stoček, R.; Kipscholl, R; Heinrich, G.:Predictive Lab Testing of Chip & Cut Failure of TiresTire Tech Expo 2014, Cologne, Germany
Euchler, E.; Stoček, Voldánová, J.; Michael, H.; Gehde, M.:Komplexe dynamische Prüfungen von Gummiqualitäten für Off-Road-ReifenTechnomer 2014, 2014, Chemnitz, Germany, ISBN 978-3-939382-11-9
Off-Road-Reifen, wie z.B. für Agrar-, Militär- oder zivile Geländefahrzeuge, kommen, verglichen mit herkömmlichen Pkw- und Lkw-Reifen, unter extremen Belastungsbedingungen zum Einsatz. Obwohl bei diesen Anwendungen die Reifen zumeist sehr langsam rotieren, werden diese aufgrund der komplexen Fahrbahnoberflächenstruktur (scharfkantige Steine, Geröll usw.) hohen Deformations- und Spannungszuständen ausgesetzt. Diese Belastungen erfordern, Off-Road-Reifen zum einen hinsichtlich der Konstruktion und des Aufbaus (z.B. verstärkte Seitenwände, größere Gummischichtdicken der Lauffläche) anzupassen und zum anderen die zu verwendenden speziellen Gummiqualitäten, insbesondere die der Lauffläche, bzgl. des Abrieb- und des Ermüdungswiderstands zu prüfen und zu klassifizieren. In dieser Arbeit soll die Eignung verschiedener Kautschukbasen für deren Anwendung in Gummiqualitäten für Off-Road-Reifenlaufflächen untersucht werden. Um realitätsnah prüfen zu können, muss neben traditioneller Prüftechnik zur Ermittlung von Ermüdungs- und Risswiderstand mittels bruchmechanischer Analyse am Tear Fatigue Analyzer auch eine spezielle Prüfung des Abriebwiderstands unter komplexen dynamischen (schlag-, stoßartigen) Bedingungen durchgeführt werden. Hierfür wurde eine an der TU Chemnitz konstruierte Prüfvorrichtung genutzt, die zur Untersuchung des Abriebwiderstands von Gummiqualitäten unter stoß- und schlagartiger Belastung dient.
Stoček, R.; Kipscholl, R.; Gehde, M.; Euchler, E.:A STUDY OF CORRELATION BETWEEN FATIGUE CRACK GROWTH AND CHIP & CUT BEHAVIORS OF REINFORCED RUBBER MATERIALSTechnomer 2014, 2014, Chemnitz, Germany, ISBN 978-3-939382-11-9
The aim of this work is concentrated on the experimental investigation of rubber fracture behavior due to Fatigue Crack Growth (FCG) as well as on the dynamic Chip&Cut (CC) analysis in laboratory. As specific results we how show the dependence of crack growth rate at given tearing energy and the dynamic rubber wear depend on the corresponding blend compositions. A comprehensive description of a newly developed advanced CC measuring system is also presented.
Stoček, R.; Ghosh, P.; Mukhopadhyay, R.; Kipscholl, R.; Heinrich, G.:Fracture behavior of rubber-like materials under classical fatigue crack growth vs. Chip & cut analysisProceedings of the 8th European Conference on Constitutive Models for Rubbers, ECCMR 2013, 25. - 28. 6. 2013, San Sebastian, Spain
The understanding of fracture behavior of rubber-like materials is of great practical importance for the prediction of rubber-like product’s life time. The aim of this work is concentrated to mechanism of tyre tread failure working in hard terrain based on the experimental determination of the fracture data with respect to real loading conditions. The relationship between Fatigue Crack Growth (FCG) and Chip & Cut (CC) behaviors of blends based on Natural Rubber (NR) and Polybutadiene Rubber (BR) suitable for tyre tread ap-plication has been investigated. The fracture mechanical analyses under real pulse as well as commercially used sinusoidal cyclic loading conditions were performed using Tear Analyzer (TA). The Chip & Cut behavior has been studied using a own developed dynamic wear testing equipment based on gravimetric determination of mass loss of test specimen and energy-input during the testing period. We demonstrate the specific re-lationship between crack growth rate at given tearing energy as well as crack growth exponent and dynamic rubber wear in dependence of blend composition.
Stoček, R.; Kipscholl, R.; Čermák, R.; Heinrich, G.:Future Trends in Tyre Characterization5th International Conference on polymeric Materials in Automotive PMA 2013 & 21th Slovak Rubber Conference SRC 2013, 23-25.04.2013, Bratislava, Slovakia
The understanding of dynamic behavior as well as fracture behavior of rubber-like materials is of great practical importance for the prediction of rubber-like product’s life time. The aim of this work is concentrated (i) to the description of mechanisms leading to rubber failure with respect to real loading conditions of the products and (ii) to a proposal resp. discussion of future trends in practical rubber characterization. We firstly demonstrate a relationship between Fatigue Crack Growth (FCG) behaviors under different loading conditions. Concluding we introduce a closed characterization method of dynamic rubber behavior with respect to tyre tread wear including the specific role of the FCG behavior of the rubber materials.
Kratina, O.; Polášková, M.; Stoček, R.; Čermák, R.:Simple method for characterization of rubber fracture in practice5th International Conference on polymeric Materials in Automotive PMA 2013 & 21th Slovak Rubber Conference SRC 2013, 23-25.04.2013, Bratislava, Slovakia
Stocek, R.; Kipscholl, R.:Polymerforschung im Herz der tschechischen GummiindustrieJahrestagung der Bezirksgruppe Ost der Deutschen Kautschuk-Gesellschaft e.V., 29.11. 2012, Dresden, Germany
Jurk, R.; Das, A.; Stöckelhuber, K.W.; Boldt, R.; Stocek, R.; Heinrich, G.; Möwes, M. M.; Karl, C.W.; Klüppel, M.:ELAGRA-Elastomerkomposite auf Basis von GraphenenInno.CNT Jahreskongress 2012, Bayreuth, 30.1.-01.02. 2012
Kipscholl, R.:Dynamischer Prüfstand zur Ermittlung der Materialeigenschaften von Elastomeren unter mehrachsigen BelastungszuständenTechnomer 2011, 10.-12.11. 2011, Chemnitz, Germany
Stoček, R.; Heinrich, G.; Gehde, M.:Neuartiges Konzept zur experimentellen Bestimmung der dynamischen Rissausbreitung in ElastomerenTechnomer 2011, 10.-12.11. 2011, Chemnitz, Germany
Stoček; R.; Reincke, K.; Heinrich, G.; Grellmann, W.; Gehde, M.:Einfluss der Kerbeinbringung auf die Rissausbreitung in elastomeren Werkstoffen13. Problemseminar "Deformation und Bruchverhalten von Kunststoffen“, 29.6.-1.7. 2011, Merseburg, Germany
Stocek, R.; Reincke, K.; Gehde, M.; Grellmann, W.; Heinrich, G.:Untersuchung zum einfluss der Kerbeinbringung auf die Rissausbreitung in Elastomeren Werkstoffen unter dynamischer BeanspruchungKHK2010, 03. - 05.11.2010, Hannover, Germany
Kipscholl, R.:Funktionstest zum Bruchverhalten von AirbagklappenTechnomer 2009, 12.-14.11. 2009, Chemnitz, Germany
Stocek, R.; Gehde, M.; Heinrich, G.:Verfahren zur Initiieren eines Anrisses im Gummiprobekörper als Grundlage für gesicherte Analyse der Rissausbreitung im GummiTechnomer 2009, 12.-14.11. 2009, Chemnitz, Germany
Stocek, R.; Gehde, M.; Heinrich, G.:Thema: Analysis of Dynamic Crack Propagation in Filled Rubbers by Simultaneous Tensile- and Pure-Shear-Mode TestingInternational Rubber Conference, 29. - 02.07. 2009, Nürnberg, Germany
Stocek, R.; Gehde, M.; Heinrich, G.:The Influence of the Test Properties on Dynamic Crack Propagation in Filled Rubbers by Simultaneous Tensile- and Pure-Shear-Mode TestingECCMR, 07.-10.09.2009, Dresden, Germany
Stocek, R.; Gehde, M.; Heinrich, G.:Analyse des dynamischen Risswachstums von Elastomerpartikel modifiziertem Gummi im simultanen Zug- und Pure-shear- Prüfmodus12. Tagung Problemseminar "Deformation und Bruchverhalten von Kunststoffen", 24. - 26.06. 2009, Merseburg, Germany
Kipscholl, R.:Produktnahes Prüfen mit Normverfahren2. Symposium Produktionstechnik innovativ und interdisziplinär im Fokus des Automobil- und Maschinenbaus, 01. - 02.04. 2009, Zwickau, Germany
KIpscholl, R.:Dynamischer Prüfstand zur Ermittlung der Materialeigenschaften von Elastomeren unter mehrachsigen Belastungszuständen13. Problemseminar,,Polymermischungen“, 25.-26.3. 2009, Merseburg, Germany
Stocek, R.; Michael, H.; Gehde, M.; Heinrich, G.:Mechanische Eigenschaften und Ermüdungsverhalten von Elastomerpartikel modifiziertem Gummi13. Problemseminar,,Polymermischungen“, 25.-26.3. 2009, Merseburg, Germany
Stocek, R.; Michael, H.; Gehde, M.; Heinrich, G.:Analysis of Dynamic Crack Propagation in Filled Rubbers by Simultaneous Tensile- and Pure Shear Mode Testing8th Rubber Fall Colloquium, 26.-28.11.2008, Hannover, Germany
Stocek, R.; Michael, H.; Gehde, M.; Heinrich, G.:Neuartige Prüfmethode zur Bestimmung der Rissausbreitung und Ermüdung von Gummi mittels TFA-GerätJahrestagung der Bezirksgruppe Ost der Deutschen Kautschuk-Gesellschaft e.V., 07.11.2008, Merseburg, Germany
Stocek, R.; Michael, H.; Gehde, M.; Heinrich, G.:Determination of tear fatigue behaviour of filled vulcanized rubber3.Kautschuk-Symposium der Donauländer, 1. Forum der Visegrad-Länder, 15.-16.10. 2008, Szeged, Ungaren
Stocek, R.; Michael, H.; Gehde, M.; Lorho, N.:Rissausbreitung und bruchmechanische Eigenschaften Gummimehl gefüllter Elastomer13. International Conference, Polymeric Materials, 24.-26.09. 2008, Halle/Saale, Germany
Stocek, R.; Michael, H.; Gehde, M.; Manas, S.:Determination of fatigue behaviour and Crack propagation of filled vulcanized rubber International doctoral seminarInternational doctoral seminar, 18.-20.05. 2008, Smolenice, Slovakia