accelerated fretting wear experimenting recommend precaution to use it in low amplitude fretting, where fretting corrosion and fretting fatigue. improved by increasing the frequency of vibration conditions, frequency influences both interfacial strain rate and temperatur Finally, only one study was found in literature fatigue tests[14]. These authors concluded that the developed ultrasonic fretting machine worked well, reproducing the phenomenon rightly. paper was to evaluate the same machine 2. Materials and Methods In order to evaluate the testing device first presented by Sun run in ultrasonic frequency, i.e., around 20kHz, until specimens 109 cycles. Fretting was induced by a cylindrical pad in right angle with the specimen (crossed cylinder configuration) with a normal load of 30N bulk load was imposed by a piezoelectric transducer in ultrasonic frequency at one of the fundamental frequencies of the specimen. material in analysis is available from earlier experiments. All tests were made at the Energétique Mécanique Electromagnétisme Ville d’Avray, France, directly linked to The device in analysis can be split in two subsystems: the ultrasonic core, responsible to axially stress the specimen, and the fretting full reverse axial stress cycles to specimens by vibrating in a frequency frequencies of the entire assembly. To achieve one these modes imposed by a piezoelectric transducer connected to a high piloted by a control unit. In general, dis small, so it was necessary to attach at one of its ends a horn (sonotrode), or mechanical amplifier, to reach desired displacements and consequently higher stress levels through specimens. core’s main units can be seen in Fig. Figure 2 – Schema of the main units composing the ultrasonic core of the testing device Once that specimen’s fundamental modes and frequency and amplitude of imposed displace at the specimen’s bottom were known, through the piece and generate the iso allowed the determination of the assure both desired fretting amplitude and bulk stress. 13th International Conference on Fracture June 16 accelerated fretting wear experimenting. However, Söderberg et al.[11] and Bryggman recommend precaution to use it in low amplitude fretting, where fretting wear is less n and fretting fatigue. Moreover, it appears that the two latter by increasing the frequency of vibration. Although there is no apparent change in contact conditions, frequency influences both interfacial strain rate and temperature. Finally, only one study was found in literature using ultrasonic frequency to accelerate fretting authors concluded that the developed ultrasonic fretting machine worked well, reproducing the phenomenon rightly. Thus, the objective of the presented same machine used by Sun et al.[14], presented in details in n order to evaluate the testing device first presented by Sun et al.[14], fretting run in ultrasonic frequency, i.e., around 20kHz, until specimens either fail or Fretting was induced by a cylindrical pad in right angle with the specimen (crossed cylinder configuration) with a normal load of 30N and constant fretting amplitude at 10µm fundamental frequencies of the specimen. Plain ultrasonic fatigue results in VHCF region for the ailable from earlier experiments. All tests were made at the ’s facilities, at Institut Universitaire de Technologie de Université Paris Ouest. can be split in two subsystems: the ultrasonic core, responsible to axially specimen, and the fretting-apparatus, in charge of rubbing it. The ultrasonic core impose cycles to specimens by vibrating in a frequency near to one of fundamental frequencies of the entire assembly. To achieve one these modes, a sinusoidal displacement wa imposed by a piezoelectric transducer connected to a high frequency power source, which wa piloted by a control unit. In general, displacements generated in a piezoelectric t s necessary to attach at one of its ends a horn (sonotrode), or mechanical amplifier, to in Fig. 2. Schema of the main units composing the ultrasonic core of the testing device that specimen’s fundamental modes and frequency and amplitude of imposed displace re known, it was easy to calculate displacement and stress fields and generate the iso-amplitude of displacement abacus. Usi the position where fretting pads were going to be placed in order to desired fretting amplitude and bulk stress. An example of this kind of June 16-21, 2013, Beijing, China 3 and Bryggman et al.[13] fretting wear is less important than the two latter phenomena rates . Although there is no apparent change in contact using ultrasonic frequency to accelerate frettingauthors concluded that the developed ultrasonic fretting-fatigue testing objective of the presented presented in details in [15]. retting-fatigue tests were or run out at the life of Fretting was induced by a cylindrical pad in right angle with the specimen (crossedconstant fretting amplitude at 10µm. Axial ultrasonic fatigue results in VHCF region for the Laboratoire The ultrasonic core imposed near to one of fundamental , a sinusoidal displacement was frequency power source, which was placements generated in a piezoelectric transducer are too reach desired displacements and consequently higher stress levels through specimens. A schema of that specimen’s fundamental modes and frequency and amplitude of imposed displacements to calculate displacement and stress fields Using this powerful tool re going to be placed in order to this kind of abacus is shown
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