Metal Manufacturing

Since the tensile strength of metals is inversely proportional to grain or crystal size, controlling and checking that the correct size is achieved during the manufacturing process is crucial in the manufacture of components such as bearings and crankshafts. Imperfections within the crystalline structure will determine how it performs under load, so being able to detect them is a key aspect of both research and development and on-going QC.

Episcopic microscopy, and in particular polarizing techniques, play a key role in allowing staff to measure grain size and spot imperfections at the interface between adjacent grains. Manual metrology provides an accurate means to assess prototypes, check the performance of CNC drilling systems and perform lower volume quality control checks. Non-contact, z-height measurement can also be a useful asset on manual measuring microscopes used for lower volume QC work.

Automated, non-contact video-based measuring not only allows multiple edge-to-edge measurements to be reliably made on large numbers of simple pressed metals components, being stamped out in their millions, but also the position, diameter, depth and profile of apertures on lower volume, complex work pieces produced as a result of a number of drilling and machining processes. With the correct microscope illumination and automated edge detection, video measuring systems can also compensate for burrs left as a result of the manufacturing process. Non-contact video measuring systems can also be used to compare CAD vs actual data, perform real-time SPC and evaluate gears.

Key techniques for checking quality control in the manufacture of metal include:stereomicroscopy; non-contact z-height measurement; non-contact video measuring systems; twin-ring LED illumination; through-the-lens laser autofocusing (TTL AF); laser scanning; automated edge detection.