Surface Roughness Inspection and Quality Control

The functionality and aesthetics of surfaces represent an essential quality characteristic of a product. Visible surface defects (e.g.. cracks, bubbles, scratches, inclusions) can restrict the function of a product or even be considered as a criterion for exclusion even if they do not necessarily lead to failure, but rather often are the cause of complaints. Surface defects can have a span of a few millimeters to a few micrometers. As part of quality control, surface roughness inspection of microscopic defects is important. Stereo and zoom microscopes are frequently used in such cases of industrial inspection. As surfaces with errors often do not have a smooth surface, dark field or ring light illumination of stereo and zoom microscopes often have advantages for good imaging of the surface. 

During machining (e.g. drilling) of different materials, the tools (drills) are exposed to constant wear. When new materials are to be drilled, a sound knowledge of the wear behavior of different drill-types is necessary. Microscopic analysis of the wear tracks is essential for this type of development. Using Zoom microscopes, a first overview of the wear and tear on the cutting edges can be achieved. For very small wear marks, a scanning electron microscope view is necessary to detect even the smallest signs of wear. 

Sealing rings in use are exposed to considerable force which can also lead to deformations of the sealing surface. When developing new sealing rings or in the quality control of existing components, a microscopic observation and an associated profile measurement is therefore appropriate. The example shows two measured seals after deployment and the profile measurements obtained.