TEM thin foil preparation for ceramic composites with multilayered matrix

A method for preparing thin foils for transmission electron microscopy (TEM) has been developed in the field of ceramic matrix composites (CMC). These composites belong to the last generation. They are developed for high temperature applications in oxidative environment (1350 °C). They possess a self-healing capability. Their design is based on a multilayered matrix. A refinement of the regular ion-milling technique was necessary to thin the samples and to proceed to a full observation of the inner matrix of the composite by TEM. In a regular CMC, the matrix is homogeneous and thereafter it has not to be fully inspected from the fiber to the surface. This sampling technique unable to thin the complete sequence of the different layers in the vicinity of large pores where the ion-milling technique is known to be very difficult. High resolution TEM as well as electron energy loss spectroscopy can be managed anywhere in the core sequence of the matrix.