Thermal Conductivity and Flash Temperature
Name
11249_2018_Article_1133.pdf
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2.62 MB
Format
Adobe PDF
Checksum (MD5)
37497e813aad216c1c425be1d5438782
Author(s)
Reddyhoff, Tom
Schmidt, Aaron J
Spikes, Hugh
Date Issued
January 2019
Journal
Tribology Letters
Publisher
Springer Science and Business Media LLC
Citation
Reddyhoff, Tom et al. "Thermal Conductivity and Flash Temperature." Tribology Letters 67, 1 (January 2019): doi.org/10.1007/s11249-018-1133-8 © 2019 The Author(s)
Version
Final published version
Abstract
The thermal conductivity is a key property in determining the friction-induced temperature rise on the surface of sliding components. In this study, a Frequency Domain Thermoreflectance (FDTR) method is used to measure the thermal conductivity of a range of tribological materials (AISI 52100 bearing steel, silicon nitride, sapphire, tungsten carbide and zirconia). The FDTR technique is validated by comparing measurements of pure germanium and silicon with well-known values, showing discrepancies of less than 3%. For most of the tribological materials studied, the thermal conductivity values measured are reasonably consistent with values found in the literature. However the measured thermal conductivity of AISI 52100 steel (21 W/mK) is less than half the value cited in the literature (46 W/mK). Further bulk thermal conductivity measurements show that this discrepancy arises from a reduction in thermal conductivity of AISI 52100 due to through-hardening. The thermal conductivity value generally cited and used in the literature represents that of soft, annealed alloy, but through-hardened AISI 52100, which is generally employed in rolling bearings and for lubricant testing, appears to have a much lower thermal conductivity. This difference has a large effect on estimates of flash temperature and example calculations show that it increases the resulting surface temperatures by 30 to 50%. The revised value of thermal conductivity of bearing steel also has implications concerning heat transfer in transmissions.
MIT Department
Massachusetts Institute of Technology. Department of Mechanical Engineering
Terms of Use
Creative Commons Attribution 4.0 International license
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1007/s11249-018-1133-8
