Spark pattern
The characteristics of a spark bush are referred to as a spark pattern , in particular its color, shape, luminosity of the spark and its length. The comparison with other spark images created in spark samples and listed in books of tables allows a rough conclusion to be drawn about the quantitative chemical composition and heat treatment of the tested material. However, this is only possible with steels , as these have a pronounced spark pattern.
Above all, high carbon contents generate a bright, flashing shower of sparks, but the high C content in high-alloy high- speed steels , for example, only results in a reddish, elongated, hardly branched spark pattern due to the hardening , as can be seen in the picture below on the right. Other alloy components can also be inferred, such as molybdenum , tungsten or manganese .
The abundance of steels available today makes interpretation much more difficult.
literature
- Gerhart Tschorn: Schleiffunkenatlas for steels, cast iron, pig iron, ferro alloys and metals. VEB German publishing house for basic industry, Leipzig 1961.
- Dieter Ollesky: Metallfachkunde 3. Construction mechanics and metal construction, BG Teubner Verlag, Stuttgart 1993, ISBN 978-3-519-06707-8 .
- Alfred Kopecky, Rudolf Schamschula: Mechanical Technology. Fourth revised edition, Springer Verlag, Vienna / New York 1977.
Web links
- Material testing by spark test (accessed January 10, 2020)
- Pforzheimer Werkstofftag 2018 (accessed on January 10, 2020)
- RWTH Aachen Newsletter (accessed January 10, 2020)
- Annual magazine for materials technology (accessed on January 10, 2020)
- Limestone, sandstone, tuff - the use of new stone materials in art classes (accessed January 10, 2020)