Neue Möglichkeiten der Gefügedarstellung von SiC-Werkstoffen

Für das Verständnis von Gefuge-Eigenschaftsbeziehungen sowie zur Aufklarung von Korrosionsmechanismen sind die detaillierten Gefugedarstellungen an keramischen Werkstoffen von großer Bedeutung. Die Möglichkeiten der detailierten Gefugedarstellung mittels hochauflosender Feldemissionsrasterelektronenmikroskopie in Kombination mit der EDX-Analyse sowie der FIB-Technik werden an polierten und elektrochemisch korrodierten LPS- (liquid phase sintered SiC) und SSiC-Werkstoffen demonstriert. Möglichkeiten der Darstellung von Diffusionszonen in halbierenden SiC-Kornem werden vorgestellt. Diese Methoden erlauben auch die durch elektrochemische Korrosion beobachteten Kern-Hulle-Strukturen zu erklaren. In order to understand the relationships which exist between the microstructutes and mechanical propeities of ceramic ma tenals and to clarify their respective mecha nisms of conosion a detailed picture of their microstructuies is of particular importance The examination of such structures using field emission scanning electron micios copy in combination with EDX analysis as well as the FIB technique are demonstrated on polished and electrochemically cor roded LPS (liquid phase sintered SiC) and SSiC materials The possibilities for reveal ing the diffusion zones in semi conducting SiC grains are presented These methods also help to explain the core shell structures caused by electrochemical corrosion.

In order to understand the relationships which exist between the microstructures and mechanical properties of ceramic materials and to clarify their respective mechanisms of corrosion, a detailed picture of their microstructures is of particular importance The examination of such structures using field emission scanning electron microscopy in combination with EDX analysis as well as the FIB technique are demonstrated on polished and electrochemically corroded LPS (liquid phase sintered SiC) and SSiC materials. The possibilities for revealing the diffusion zones in semi-conducting SiC grains are presented These methods also help to explain the core-shell structures caused by electrochemical corrosion.