Correlation of metrological surface parameters to the strength of advanced ceramics.

摘要

Surface topography greatly influences not only the mechanical and physical properties of contacting parts, but also the optical and coating properties of contacting components. The characteristics of surface topography in amplitude, spatial distribution and pattern of surface features dominate the functional applications in the field of wear, friction, lubrication, fatigue, sealing, joining, reflecting, painting, etc. Although surface roughness data from a stylus profilometer continues to be of basic importance, it does suffer from some limitations which cannot be overlooked. Some of the major limitations of using a stylus profilometer are finite tip radius, inability to record detailed information, bouncing of stylus tip and losing contact with surface, the stylus might create scratches as it passes over the surface, and long time when acquiring data.;Alternatively, optical interferometry has, for a number of decades, been used to measure surface topography successfully. As a result there are many commercial interferometric instruments based on two or multi-beam interferometerss instruments available today.;The goal of this thesis is to continue to work on the development of a novel method that can obtain the topography of surfaces utilizing advanced digital moire. In the version under development a grating printed on a glass plate will be utilized to generate fringes. The HoloStrain software is utilized to process the fringe pattern information.;The main objective of the thesis is to apply this methodology to measuring the surface roughness of ceramics that have been modified via laser-assisted machining. This research will enable further development of the laser-assisted machining process by making it feasible to optimize the surface profile of the ceramic through changing processing parameters.