Atomic force microscopy of transfer film development

Shaffer, Kathryn1 ; McCumiskey, Edward2 ; Krick, Brandon3 ; Ewin, Jeffrey4 ; Taylor, Curtis2 ; Junk, Christopher5 ; Blackman, Gregory6 ; Sawyer, W. Gregory7 ; Pitenis, Angela 1

Published Jul 19, 2024 on Dryad. https://doi.org/10.5061/dryad.zpc866thd

Data files

Jul 19, 2024 version files 1.29 GB

2024_Shaffer_TribLettAFM_DataDryad.zip

1.29 GB
README.md

8.52 KB

Abstract

Atomic force microscopy (AFM) provides the opportunity to perform fundamental and mechanistic observations of complex, dynamic, and transient systems and ultimately link material microstructure and its evolution during tribological interactions. This investigation focuses on the evolution of a dynamic fluoropolymer tribofilm formed during sliding of polytetrafluoroethylene (PTFE) mixed with 5 wt% alpha-phase alumina particles against 304L stainless steel. Sliding was periodically interrupted for AFM topography scans. The average film roughness, the average friction coefficient, and polymer wear rate based on sample height recession were recorded as a function of increasing sliding cycles. Topographical maps suggest tribofilm nucleates in grooves of the steel counter sample, spreads and develops into a uniform film through sliding. Prominent nanoscale features were visible around 10,000 sliding cycles and thereafter. Scanning electron microscopy and energy-dispersive X-ray spectroscopy showed good correlations between these features and aluminum-rich domains, suggesting the presence of alumina particles on the surface.

https://doi.org/10.5061/dryad.zpc866thd

Corresponding Author: Angela A. Pitenis apitenis@ucsb.edu

File List

A) AFM_Region_1.zip

B) AFM_Region_2.zip

C) AFM_Region_3.zip

D) AFM_Region_4.zip

E) Countersurface.zip

F) Fig3_AverageRoughness.csv

G) Fig3_FrictionAndWear.csv

H) Fig5_Al.tif

I) Fig5_SI.tif

J) Fig6.csv

K) FigS1_0s.tif

L) FigS1_5s.tif

M) FigS1_10s.tif

N) FigS2_10k.tif

O) FigS2_20k.tif

P) FigS2_30k.tif

Q) FigS2_40k.tif

R) FigS2_50k.tif

S) FigS2_100k.tif

T) FigS2_all.jpg

U) FigS3.csv

V) FigS4_10k.ibw

W) FigS4_20k.ibw

X) FigS4_30k.ibw

Y) FigS4_40k.ibw

Z) FigS4_50k.ibw

AA) FigS4_100k.ibw

AB) FigS5.csv

Figures 1, 2, 4, SV1: AFM Data

A) AFM_Region_1.zip: zip folder containing IBW files for each AFM scan done in region 1 on the primary sample. These files are labeled Region1_Cycle_X, where X is the cycle number the AFM scan was taken. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

B) AFM_Region_2.zip: zip folder containing IBW files for each AFM scan done in region 2 on the primary sample. These files are labeled Region2_Cycle_X, where X is the cycle number the AFM scan was taken. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

C) AFM_Region_3.zip: zip folder containing IBW files for each AFM scan done in region 3 on the primary sample. These files are labeled Region3_Cycle_X, where X is the cycle number the AFM scan was taken. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

D) AFM_Region_4.zip: zip folder containing IBW files for each AFM scan done in region 4 on the primary sample. These files are labeled Region4_Cycle_X, where X is the cycle number the AFM scan was taken. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

Figures 1, 2, SV1: Countersurface Images

E) Countersurface.zip: zip folder containing JPG images of the countersurface of the primary sample. These files are labeled Countersurface_Cycle_X, where X is the cycle number the AFM scan was taken.

Figure 3, SV1: Roughness, Friction and Wear Data

F) Fig3_AverageRoughness.csv: average roughness values for countersurface of the primary sample.

Row 1: labels for column data with units
Column A: number of sliding cycles
Column B: average roughness, in nanometers
Column C: uncertainty in average roughness, in nanometers

G) Fig3_FrictionAndWear.csv: coefficient of friction and wear rate values for the primary sample.

Row 1: labels for column data with units
Column A: number of sliding cycles
Column B: average friction coefficient, unitless
Column C: uncertainty in average friction coefficient, unitless
Column D: wear rate, in millimeters cubed per Newton-meter

Figure 5: SEM micrograph

H) Fig5_Al.tif: EDX map of the countersurface of the stripe test sample after 50,000 sliding cycles displaying of location of aluminum, in purple. Brighter purple indicates a greater abundance of aluminum.

I) Fig5_SI.tif: secondary electron micrograph of the countersurface of the stripe test sample after 50,000 sliding cycles.

Figure 6: PSD data

J) Fig6.csv: power spectral density data for the primary sample countersurface taken from AFM maps for representative sliding cycles. Data was produced on the contact.engineering web platform and can be found at https://doi.org/10.57703/ce-p4z34.

Row 1: labels the number of sliding cycles for the two columns below the label
Row 2: Labels for column data with units
Column A: Wavevector for 0 sliding cycles, in inverse meters
Column B: Power spectral density for 0 sliding cycles, in meters cubed
Column D: Wavevector for 5,000 sliding cycles, in inverse meters
Column E: Power spectral density for 5,000 sliding cycles, in meters cubed
Column G: Wavevector for 10,000 sliding cycles, in inverse meters
Column H: Power spectral density for 10,000 sliding cycles, in meters cubed
Column J: Wavevector for 100,000 sliding cycles, in inverse meters
Column K: Power spectral density for 100,000 sliding cycles, in meters cubed

Figure S1: SEM micrographs

K) FigS1_0s.tif: secondary electron micrograph of the countersurface of the stripe test sample after 50,000 sliding cycles taken as blisters began forming.

L) FigS1_5s.tif: secondary electron micrograph of the countersurface of the stripe test sample after 50,000 sliding cycles taken 5s after blisters began forming.

M) FigS1_10s.tif: secondary electron micrograph of the countersurface of the stripe test sample after 50,000 sliding cycles taken 10s after blisters began forming.

Figure S2: Countersurface Images

N) FigS2_10k.tif: micrograph of the stripe test countersurface at 10,000 sliding cycles

O) FigS2_20k.tif: micrograph of the stripe test countersurface at 20,000 sliding cycles

P) FigS2_30k.tif: micrograph of the stripe test countersurface at 30,000 sliding cycles

Q) FigS2_40k.tif: micrograph of the stripe test countersurface at 40,000 sliding cycles

R) FigS2_50k.tif: micrograph of the stripe test countersurface at 50,000 sliding cycles

S) FigS2_100k.tif: micrograph of the stripe test countersurface at 100,000 sliding cycles

T) FigS2_all.jpg: image of the entire stripe test countersurface

Figure S3: Wear Rate

U) FigS3.csv: wear rate of the stripe test sample

Row 1: labels for column data with units
Column A: sliding distance, in meters
Column D: wear rate, in millimeters cubed per Newton-meter

Figure S4: AFM Images

V) FigS4_10k.ibw: representative AFM image of the stripe test sample in the region that was slid for 10,000 sliding cycles. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

W) FigS4_20k.ibw: representative AFM image of the stripe test sample in the region that was slid for 20,000 sliding cycles. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

X) FigS4_30k.ibw: representative AFM image of the stripe test sample in the region that was slid for 30,000 sliding cycles. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

Y) FigS4_40k.ibw: representative AFM image of the stripe test sample in the region that was slid for 40,000 sliding cycles. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

Z) FigS4_50k.ibw: representative AFM image of the stripe test sample in the region that was slid for 50,000 sliding cycles. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

AA) FigS4_100k.ibw: representative AFM image of the stripe test sample in the region that was slid for 100,000 sliding cycles. IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software.

Figure S5: PSD Data

AB) FigS5.csv: power spectral density data for the stripe test sample countersurface taken from AFM maps for representative sliding cycles. Data was produced on the contact.engineering web platform and can be found at https://doi.org/10.57703/ce-4sty6.

Row 1: labels the number of sliding cycles for the two columns below the label
Row 2: Labels for column data with units
Column A: Wavevector for 10,000 sliding cycles, in inverse meters
Column B: Power spectral density for 10,000 sliding cycles, in meters cubed
Column D: Wavevector for 20,000 sliding cycles, in inverse meters
Column E: Power spectral density for 20,000 sliding cycles, in meters cubed
Column G: Wavevector for 30,000 sliding cycles, in inverse meters
Column H: Power spectral density for 30,000 sliding cycles, in meters cubed
Column J: Wavevector for 40,000 sliding cycles, in inverse meters
Column K: Power spectral density for 40,000 sliding cycles, in meters cubed
Column M: Wavevector for 50,000 sliding cycles, in inverse meters
Column N: Power spectral density for 50,000 sliding cycles, in meters cubed
Column P: Wavevector for 100,000 sliding cycles, in inverse meters
Column Q: Power spectral density for 100,000 sliding cycles, in meters cubed

Code/Software

IBW files may be opened using Gwyddion, a free scanning probe microscopy data analysis software available at http://gwyddion.net/.