Experimental and numerical calculation data of contact stiffness/Surface roughness/HPT
Fukagai, Shinya (2022), Experimental and numerical calculation data of contact stiffness/Surface roughness/HPT, Dryad, Dataset, https://doi.org/10.5061/dryad.12jm63z01
Understanding the dynamic condition of the interface between a railway wheel and rail is important to reduce the risks and consider the effectiveness of countermeasures for tribological problems. Traditionally the difficulty in obtaining accurate non-destructive interfacial measurements has hindered systematic experimental investigations. Recently an ultrasound reflectometry technique has been developed as a direct observation method of a rolling-sliding interface, however the topography dependence under the high contact pressures in a wheel-rail contact has not been clarified. For this reason, a novel in-situ measurement of the contact stiffness using ultrasound reflectometry was carried out for three different levels of roughness. A contact pressure equivalent to that in a wheel-rail interface was achieved by using a high-pressure torsion test approach. The dynamic change of contact stiffness with slip was measured using ultrasound and the influence of roughness was investigated. The measured changes were validated using a newly developed numerical simulation, and mechanisms to explain the observed behaviour were proposed in terms of fracture and plastic deformation of the asperity bonds. These findings could help in understanding the traction characteristics for different roughness conditions and also assist in understanding damage mechanisms better, such as wear and rolling contact fatigue.
Contact stiffness: measured by ultrasound reflectometry and calculated based on a Boundary Element Method (BEM)
Roughness: measured using a contact roughness meter (Mitutoyo Surftest SJ-210) with a cut-off of 0.8 mm and a length of 2.4 mm
Loads etc: high-pressure torsion (HPT) test
The test numbers te12, 18, and 19 represent medium roughness, high roughness, and low roughness, respectively.
- ‘Ultrasound and HPT_final’ folder:
This folder contains the experimental and numerical data plotted in Figures 10~13, 16~19, 20 and 22.
- 'Roughness_final' folder:
This folder contains the data of roughness curve of top and bottom specimens before and after the tests. They were measured using a contact roughness meter (Mitutoyo Surftest SJ-210) with a cut-off of 0.8 mm and a length of 2.4 mm
- 'Numerical calculation_final' folder:
The raw data of numerical calculation code will be provided with the surface topography data.