Surface Analysis

Optimizing surface character can improve product performance in virtually every industry, but desired behaviour can vary greatly with intended application. In many industries, for example, a high degree of roughness is undesirable as it causes friction, wear and fatigue, which can ultimately lead to the premature breakdown of components. In other industries, a certain amount of roughness can be beneficial as it enables surfaces to trap lubricants more easily. Surface metrology is also used to support research in a variety of fields from the analysis of minerals in geology, to the development of novel medical devices, where the latest generation of implants are using new finishes to reduce the adhesion of bacteria and the development of detrimental biofilms.

In order to assess variances in surface texture, metrologists rely on a variety of microscopic techniques from simple brightfield analysis to differential interference contrast microscopy (DIC), interferometry and polarization analysis. Depending on the intended application of the material or object, the scale of interest can vary from the micron to the nanometer, but in every case the quality of the objectives is paramount. Accurate analysis of texture can reveal the crucial topographical characteristics that determine functional capabilities, limitations and the overall performance of products and devices.

3D laser scanning provides users a metrology tool to obtain a highly accurate representation of the objects' surface for comparison to CAD.

Key terms techniques: Brightfield microscopy, polarization, DIC, interference, metrology