Dynamic contact strain measurement by time-resolved stroboscopic energy dispersive synchrotron X-ray diffraction

Research output: Contribution to journalArticlepeer-review

Authors

  • M. Mostafavi
  • M. J. Peel
  • C. Reinhard
  • S. M. Barhli
  • R. Mills
  • M. B. Marshall
  • R. S. Dwyer-Joyce
  • T. Connolley

Colleges, School and Institutes

External organisations

  • University of Bristol
  • Oxford University
  • Diamond Light Source
  • Sheffield University

Abstract

Recent developments of synchrotron X-ray sources and dedicated high-energy beamlines are now enabling strain measurements from large volumes of industrially relevant metallic materials. Such capability is allowing the validation of novel and alternative nondestructive experimental methods of strain measurement or computational models of complex deformation processes. This study describes the first dynamic contact strain measurement of a ball bearing using stroboscopic energy dispersive X-ray diffraction. The experiment probed the dynamic contact strain in the outer raceway of a test bearing. The inner raceway of the bearing was attached to a shaft rotating at 150 revolutions per minute, and the outer raceway, where the measurements were made, was fixed in a stationary bearing housing. A triggering system was used to synchronise the data acquisition of the energy dispersive X-ray diffraction detector with the bearing rotation. Specifically, diffraction data were acquired, stroboscopically, from the material volume within the raceway, in a known location, when the ball was positioned directly below it. A total of 20 s of accumulated diffraction signal was recorded, acquiring 2 ms of data per revolution, providing diffraction patterns of sufficient quality for the dynamic contact strain to be measured. Macromechanical stress field was calculated from the micromechanical strains measured from five lattice planes. This allowed a comparison of the experimentally measured stress field and that of finite element simulations. Good agreement was observed between the finite element results and experimental measurements indicating the applicability of this novel dynamic strain measurement technique for tribological systems.

Details

Original languageEnglish
Article numbere12221
JournalStrain
Volume53
Issue number2
Early online date23 Jan 2017
Publication statusPublished - 1 Apr 2017

Keywords

  • contact stress, energy dispersive X-ray diffraction, finite element analysis, stroboscopic measurement, tribology