1. Pure Ni Raman spectroscopy wear map CNT-Ni Raman spectroscopy wear map
In situ Chemical Diagnostic Tribology of Dry and Lubricated Thin Film-Based Technologies
Thomas W. Scharf, Department of Materials Science and Engineering, The University of North Texas
Auger electron spectroscopy map of unworn carbon nanotube (CNT) - Ni composite
Pure Ni Raman spectroscopy wear map
CNT-Ni Raman spectroscopy wear map
Green=Ni and Red=C.
50 mm
50 mm
1200
1400
1600
1800 D' G
Raman Shift (cm -1 )
Intensity (arb. units)
1604 D
1582
worn
Ni-CNT
400
600
800
1000
NiO
Intensity (arb. units)
Raman Shift (cm -1 )
553
unworn
Ni-CNT
CNT
powder
Raman determined wear-induced:
Formation of an in situ, low interfacial shear strength graphitic film.
Increased graphitization indicated by shift in G-peak, increased ID/IG and peak FWHM.
500 nm
Mechanisms of solid and self-lubrication have been determined for Ni-CNT composites by in situ Raman spectroscopy spatial mapping worn surfaces to determine the formation of tribochemical products. The composites exhibit a self-lubricating behavior, forming an in situ, low interfacial shear strength tribochemcial graphitic film during sliding, resulting in a decrease in coefficient of friction (COF) compared to pure Ni.