TEM STUDY ON STRUCTURE OF GRAPHITE IN RE-TREATED CAST IRON

The thin foil samples of rare earth treated cast iron. were analysed by means of TEM. The results confirmed that the <0001> direction of graphite crystal is perpendicular to the "annual ring" lines revealed by ion bombardment. Each cone in a nodular graphite is composed of many microcrystallites with a small angle each other in their orientations. The morie patterns in the TEM picture of the graphite were also analysed. It is considered that they result from some structure defects such as twins existing in the graphite.