Impact Testing of Spheres against Thin Film Substrates

Due to their ability to maintain low friction at demanding loading conditions, rolling element bearings (REB) have come to represent the main form of velocity accommodation in industrial, aerospace, energy, and automotive applications. As REB designs become optimized, efforts to increase bearing performance require stepping into innovative realms of tribology such as solid lubricant coatings. While coatings have been well-studied, very little has been elucidated as to the science behind their success. For instance, while initially acting to prevent the deterioration of bearing surfaces, their own breakdown is still not well understood. This work aims to study solid lubricant coating damage due to sphere impact, and its effects on the coating properties related to enhanced bearing performance such as abrasion resistance and friction reduction. The slow motion video shows a silver metal ball dropping against a thin film substrate.
impact testing
PFTL Research Assistant(s):   Martin C. Marinack Jr.; Patrick S. M. Dougherty; Deepak C. Patil
Method(s) Employed:   High Speed Video, Image Processing, Optical Interferometry, Explicit Finite Element Modeling (FEM), High/low speed and load tribometry, in situ data acquisition
Rig(s) and/or Software(s) Employed:   Drop Test Rig, Photron FASTCAM SA4 High Speed Camera, Vision Research Phantom v7.1 High-Speed Camera, Zygo New-View 7300 Optical Interferometer, Bruker UMT-3 Tribometer, Hysitron Nanoindenter, LS-DYNA, Mathematica
Sponsor(s):   Timken, NSF Graduate Research Fellowship

Sample Results:



Select PFTL References:

Dougherty, P.S.M., Marinack Jr., M.C., Higgs III, C.F., 2013, "INSERT TITLE HERE" STLE Annual Meeting and Exhibition 2013, Detroit, MI.