Abstract
The Ti36.2Zr30.3Cu8.3Fe4Be21.2 (at.%) bulk metallic glass (BMG) exhibits a regular micrometer-sized pattern in the transmission electron microscope (TEM) after ion milling. Quantitative energy-dispersive X-ray spectroscopy (EDX) results show that the compositions in the bright and dark regions are distinctly different, and the compositions gradually change with the contrast of the pattern. In the intermediate regions (with grey contrast) preferential crystallization is observed and this confirms that microscale heterogeneities exist in the ion-milled TEM specimens. On the contrary, the specimens prepared by focused ion beam and by electrolytic thinning show featureless microstructures in the TEM. Moreover, EDX results and the secondary ion mass spectroscopy show that the constituent elements are homogeneously distributed. An ion milling-induced compositional fluctuation mechanism is proposed, and the partial devitrification can be explained based on this mechanism. The present findings may lead to a deeper understanding of the occurrence of micrometer-sized heterogeneities in BMGs induced by ion milling.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have