What is ledeburite and perlite insulation

Is the structural name for a crystal mixture of ferrite and cementite crystals arranged side by side in plate-like form. According to the iron-carbon diagram, pearlite is formed in hypoeutectoid steels through the disintegration of austenite when it cools below 723 ° C. After cooling, hyperutectoid steels have a structure of pearlite with additional secondary cementite on the grain boundaries. The mechanical properties of unalloyed steels are not only determined by the ratio of ferrite to pearlite and the grain size; the distance between the cementite lamellae in the pearlite also plays an important role: the smaller the lamellae distance, the higher the strength. Therefore, the resulting perlite is characterized as coarse, fine or very fine lamellar. The former terms sorbitol (fine lamellar perlite) and troostite (finest lamellar perlite) are no longer included in a standard and are hardly used any more.

see austenite
see iron-carbon diagram
see ferrite
see cementite