SCANNING PROBE MICROSCOPY OF CARBON-FIBER SURFACES

In order to gain a better understanding of the role that the carbon fiber surface plays in adhesion, it is necessary to be able to observe it at atomic dimensions. Two scanning probe microscopes have been found to be particularly useful for this task. Both the scanning tunneling microscope (STM) and the atomic force microscope (AFM) use probes that are precisely rastered across the surface with piezoelectric tubes. These microscopes are able to image atomic topology and have been used by several investigators to characterize various carbon fiber surfaces. The effects of various carbon fiber surface treatments have also been documented by the STM. In the normal force mode, the AFM has been shown to be useful in documenting the growth of silica deposits on the fiber surface, while in the force modulation mode the AFM is able to display an image that contains information on the modulus of the surface, in addition to topographical information. Various other scanning probe microscopes are discussed.