The Experts below are selected from a list of 172518 Experts worldwide ranked by ideXlab platform
Yijun Shi - One of the best experts on this subject based on the ideXlab platform.
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the effect of thermal conductivity and friction coefficient on the Contact Temperature of polyimide composites experimental and finite element simulation
Tribology International, 2012Co-Authors: Yijun Shi, Xin Feng, Jiahua ZhuAbstract:Abstract In this work, the Finite Element Method is used to simulate and visualize the maximum Contact Temperature of polymer composites under ring-on-block tribolgical test. The simulated Temperatures are in good agreement with the experimental results under all testing conditions. The error values between the experimental and simulated Temperature are less than 10%. The Contact Temperature is decreased to nearly 72 °C just by reduction of the friction coefficient by 40%, which is about 18 times higher than the 40% increase of thermal conductivity. The results indicate that the friction coefficient plays a more important role in the Contact Temperature than the thermal conductivity.
Jiahua Zhu - One of the best experts on this subject based on the ideXlab platform.
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the effect of thermal conductivity and friction coefficient on the Contact Temperature of polyimide composites experimental and finite element simulation
Tribology International, 2012Co-Authors: Yijun Shi, Xin Feng, Jiahua ZhuAbstract:Abstract In this work, the Finite Element Method is used to simulate and visualize the maximum Contact Temperature of polymer composites under ring-on-block tribolgical test. The simulated Temperatures are in good agreement with the experimental results under all testing conditions. The error values between the experimental and simulated Temperature are less than 10%. The Contact Temperature is decreased to nearly 72 °C just by reduction of the friction coefficient by 40%, which is about 18 times higher than the 40% increase of thermal conductivity. The results indicate that the friction coefficient plays a more important role in the Contact Temperature than the thermal conductivity.
Mitjan Kalin - One of the best experts on this subject based on the ideXlab platform.
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influence of flash Temperatures on the tribological behaviour in low speed sliding a review
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2004Co-Authors: Mitjan KalinAbstract:Abstract Tribochemical reactions always occur in dynamic and complex Contact situations where the mechanical and thermal effects are acting simultaneously, and both are influencing the result. This is why different—and sometimes contradictory—assessments of the importance of thermal and mechanical effects on tribochemical reactions are reported in the literature. An indicative and interesting example is that of sliding at very low sliding speeds. Namely, at low sliding speeds the Contact Temperatures should be low. Therefore, the tribochemical reactions should be a consequence of the broadly prevailing mechanical factors. On the other hand, our results show that very high Temperatures could occur at the asperity spot-to-spot Contacts and that it could be these very high Temperatures that are mainly responsible for the tribochemical reactions and various phase transformations, even under very low-speed conditions. However, the possibilities for determining the Contact Temperature and obtaining the reliable evidence are rather limited and their accuracy is suspect. In this paper, we discuss various possibilities for determining the Contact Temperatures and point out the difficulties and uncertainties related to these techniques, particularly when it comes to defining the Temperature at the asperity Contacts. Accordingly, we suggest that several independent techniques for determination of the maximum Contact Temperature should be used to increase the reliability of the interpretation of the results.
Stefano Gialanella - One of the best experts on this subject based on the ideXlab platform.
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Pin-on-Disc Testing of Low-Metallic Friction Material Sliding Against HVOF Coated Cast Iron: Modelling of the Contact Temperature Evolution
Tribology Letters, 2017Co-Authors: Matteo Federici, Giovanni Straffelini, Stefano GialanellaAbstract:Pin-on-disc (PoD) testing is widely used to investigate the sliding behaviour of materials and relevant wear mechanisms under different tribological conditions. The approach has been also profitably applied to the characterization of materials for brake systems to obtain specific information on the wear mechanisms. In the present study, the transient thermal analysis of a pin made with a friction material dry sliding against HVOF coated and uncoated pearlitic cast iron disc in a PoD apparatus was investigated by means of a finite element analysis together with experimental measurements. The aim of the investigation was to model the surface Contact Temperature in this sliding system to highlight the role of the different surface conditions, i.e., coated and uncoated, on the evolution of the pin and disc Temperatures during sliding. In addition, we propose a simplified analytical equation for estimating the average Temperature rise in the Contact region during sliding, by extending the Kennedy approach in order to be able to provide a quick evaluation of the Contact Temperature for this kind of couplings, what is very helpful when characterizing a large number of systems in different Contact conditions.
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Wear and Contact Temperature Evolution in Pin-on-Disc Tribotesting of Low-Metallic Friction Material Sliding Against Pearlitic Cast Iron
Tribology Letters, 2016Co-Authors: Giovanni Straffelini, Piyush Chandra Verma, Sergey Verlinski, Giorgio Valota, Stefano GialanellaAbstract:Pin-on-disc tribotesting is widely used to investigate the sliding behaviour of materials, including friction materials used in braking systems. The evaluation of the average Contact Temperature is paramount to understand the acting friction and wear mechanisms, and to determine the role of the materials. In the present work, the tribological behaviour of a commercial low-metallic friction material during dry sliding against a pearlitic cast iron has been investigated and the evolution of pin and disc Temperature was recorded. The Temperature distributions in the pin and the disc were modelled using a finite element analysis with three different approaches, i.e. considering a perfect Contact, the separated bodies concept, and the presence of a third body between the sliding surfaces. The results were then discussed by considering the damaging phenomena occurring at the sliding Contact. Wear was found to be nearly mild in nature in agreement with the Contact Temperatures that were determined to be lower than 100 °C. During sliding, a limited third body was formed, made of a partially covering friction layer on the pin surface, and a thin and irregular oxide layer on the cast iron wear track. The approach based on the perfect Contact with thermal continuity at the interface was found to better fit the experimental Temperature records and to be in substantial agreement with the observed wear phenomena occurring at the pin–disc interface.
T H C Childs - One of the best experts on this subject based on the ideXlab platform.
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metal cutting experiments and modelling for improved determination of chip tool Contact Temperature by infrared thermography
Cirp Annals-manufacturing Technology, 2015Co-Authors: Pedroj Arrazola, P Aristimuno, D Soler, T H C ChildsAbstract:Abstract Temperature measurement in metal cutting at the chip and work Contact is of central importance due to Temperature dependence of tool wear and surface integrity. Infrared thermography is commonly employed to determine the tool side face Temperature in orthogonal cutting but Temperature needs to be estimated at the tool chip Contact area. This experimental and modelling study of AISI 4140 steel and Ti6Al4V titanium alloy cut respectively by P and K grade cemented carbide tools at practical cutting speeds and feeds shows the relationship between side face and in-Contact Temperature, for the more certain use of the infra-red thermography method.