The Experts below are selected from a list of 34695 Experts worldwide ranked by ideXlab platform
Yves Berthier - One of the best experts on this subject based on the ideXlab platform.
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Friction and lifetime of a contact lubricated by a solid third body formed from an MoS1.6 coating at low temperature
Wear, 2015Co-Authors: Sylvie Descartes, Claude Godeau, Yves BerthierAbstract:A special test device has been designed to investigate the Friction and wear behaviour of materials under very low temperature conditions. This paper describes an analysis of Friction and wear in sliding contacts “lubricated” by a solid third body formed in situ from a non-stoichiometric MoS1.6 coating at 297K, 223K, 173K and 123K, under reciprocating kinematics in a gaseous atmosphere. It was found that under given test conditions, the Friction coefficient was somewhat higher at low temperature than at room temperature under oxidising atmosphere.The lifetime was ten times lower at 123K than at room temperature. Under no oxidising atmosphere the temperature does not effect on the Friction Value. The consequences of decreasing temperature on Friction and lifetime are interpreted on the basis of experimental evidence and from the view point of mechanics in order to evaluate third body flows and the rheology activated in the contact.
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tribological physicochemical and thermal study of the abrupt Friction transition during carbon carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Abstract Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (∼0.15) to a high Value (∼0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
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Tribological, physicochemical and thermal study of the abrupt Friction transition during carbon/carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (not, vert, similar0.15) to a high Value (not, vert, similar0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
Pascale Jacquemard - One of the best experts on this subject based on the ideXlab platform.
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tribological physicochemical and thermal study of the abrupt Friction transition during carbon carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Abstract Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (∼0.15) to a high Value (∼0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
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Tribological, physicochemical and thermal study of the abrupt Friction transition during carbon/carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (not, vert, similar0.15) to a high Value (not, vert, similar0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
Haytam Kasem - One of the best experts on this subject based on the ideXlab platform.
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tribological physicochemical and thermal study of the abrupt Friction transition during carbon carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Abstract Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (∼0.15) to a high Value (∼0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
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Tribological, physicochemical and thermal study of the abrupt Friction transition during carbon/carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (not, vert, similar0.15) to a high Value (not, vert, similar0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
Sylvie Bonnamy - One of the best experts on this subject based on the ideXlab platform.
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tribological physicochemical and thermal study of the abrupt Friction transition during carbon carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Abstract Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (∼0.15) to a high Value (∼0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
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Tribological, physicochemical and thermal study of the abrupt Friction transition during carbon/carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (not, vert, similar0.15) to a high Value (not, vert, similar0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
Philippe Dufrenoy - One of the best experts on this subject based on the ideXlab platform.
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tribological physicochemical and thermal study of the abrupt Friction transition during carbon carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Abstract Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (∼0.15) to a high Value (∼0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
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Tribological, physicochemical and thermal study of the abrupt Friction transition during carbon/carbon composite Friction
Wear, 2009Co-Authors: Haytam Kasem, Yves Berthier, Sylvie Bonnamy, Philippe Dufrenoy, Pascale JacquemardAbstract:Due to their thermo-mechanical performances maintained at high temperature, C/C composites demonstrate their advantages in high energy aeronautical braking. During Friction a typical tribological behavior was observed. At first, an abrupt transition of Friction coefficient takes place systematically from a weak Value (not, vert, similar0.15) to a high Value (not, vert, similar0.35). Before this transition, an extremely weak wear rate is associated to a weak Friction coefficient Value and no gas exchanges occur in the contact, this regime being called non-reactive. From the abrupt transition, a very high wear rate and strong gas exchanges associated to the high Friction Value occur (reactive regime). In this paper, for a better understanding of the mechanisms governing the abrupt transition during C/C composites tribological, mechanical, thermal and physico-chemical data are analyzed. Friction tests are performed on a 3D C/C composite consisting of PAN-based fibers and CVI pyrocarbon matrix in using a pin-on-disc tribometer equipped with a mass spectrometer allowing the in situ gas exchange analysis (CO2 production, O2 consumption) in the contact. To follow the disc surface temperature evolution before, during and after the transition, a thermal infrared camera is used. After Friction, worn surfaces and interfaces are characterized by optical microscopy and scanning electron microscopy. In a final analysis, a mechanism is proposed to explain the abrupt transition.
