Confocal microscope observation of graphite morphology

New microscopical techniques allow to observe different tomographic section s of flake, compact and spheroidal graphite, and confirms some of the theor ies of growth mechanisms and rejects some others. Confocal microscopy (CSLM ), as a non destructive and high resolution technique, is used for obtainin g optical z-sections, In our case, the first step is to dissolve completely the metallic matrix in order to let the graphite free of interacting eleme nts or interference parts. Graphite are then observed under a laser beam. W e found out that graphites are transparent to the beam. Thus, it was possib le to cut them optically using the reflection mode at each focal section. F urther, 3-D reconstructed images are produced, We present these images obta ined by the confocal microscope which have permitted us to observe the inte rnal graphite morphology and help to understand the graphite growth mechani sm. Also, using EDS, TEM and Auger spectroscopical analysis, we have studie d in commercial irons with different melt treatments their nuclei and deter mined the real germs which are related to the heterogeneous nucleation theo ry.