Imaging Dislocations in Duplex Tial Using Electron Channeling Contrast

Autor:	T. R. Bieler, M. A. Crimp, B. C. Ng
Rok vydání:	1999
Předmět:	Nuclear magnetic resonance Materials science Duplex (building) media_common.quotation_subject Contrast (vision) Electron Instrumentation media_common
Zdroj:	Microscopy and Microanalysis. 5:882-883
ISSN:	1435-8115 1431-9276
Popis:	Electron channeling contrast imaging (ECCI), performed using a scanning electron microscope, has been used to observe dislocations in bulk TiAl with a duplex microstructure. The ECCI technique is based on the dependence of the back-scattered electron (BSE) yield (of the incident beam orientation) on the crystal lattice and defect orientation near the specimen surface. This allows nearsurface defects to be imaged in bulk specimens [1, 2]. ECCI was carried out in a Camscan 44FE FEG-SEM operated at 25 kV using a beam divergence of ∽8 mrad and a beam current of ∽ 2nA. Specimens were observed at a working distance of approximately 11 mm. To record the BSE signal, the microscope was fitted with an annular (four quadrant) silicon diode detector array attached to the final lens pole-piece, resulting in a solid angle collection of approximately ∽0.6 π str. Images were recorded as 32 frame averages using ∽1.1 frames/sec.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::4d98af94ac106b4b84aedc2b7d32a51c https://doi.org/10.1017/s1431927600017736 Zobrazit plný text záznamu