TEM preparation technique influence on an LBM AlSi7Mg0.6 alloy nanostructure

Abstract

To provide detailed characteristics on the laser beam melting AlSi7Mg0.6 alloy, transmission electron microscopy is required as the microstructure is composed of aluminum cells hardened by nano-sized precipitates encapsulated in a 3D silicon structure. However, sample preparation techniques can cause local temperature variation or irradiation that impact the local microstructure. With various thin-foil preparations, we have shown that standard twin jet electropolishing produce thin, well-defined aluminum cells filled with nano-sized precipitates. When ion-based methods are used, due to local heating and irradiation, the nanoprecipitates are significantly altered. Lowering the preparation technique temperature appears to be equivalent to twin jet electropolishing.