Subsequent to moving into new facilities in autumn last year, our new materials laboratory has been pepared and equipped during the last weeks in order to start operation now. For the purpose of metallography, a cutting machine with 300 mm disc diameter, a mounting press and an automic grinding and polishing machine are now available. With these devices metallographic specimens can be taken from e. g. bearings and gears.
Metallographic specimens will be investiged by optical microscopy in order determine degree of cleanliness, kind and size of inclusions and to identify material defects such as cracks, cavities etc. For investigation of microstructure, specimens have to be etched while the etching medium needs to be chosen according to material properties. For typical bearing steels, for example, nital etching (alcoholic resolution of nitric acid) is very common.
Apart from an optical microscope which allows amplification by up to 1000 times, a stereo loupe is available which is very helpful for investigation of fracture faces and worn surfaces.