Quantitative atom probe analysis of carbides
Artikel i vetenskaplig tidskrift, 2011

Compared to atom probe analysis of metallic materials, the analysis of carbide phases results in an enhanced formation of molecular ions and multiple events. In addition, many multiple events appear to consist of two or more ions originating from adjacent sites in the material. Due to limitations of the ion detectors measurements generally underestimate the carbon concentration. Analyses using laser-pulsed atom probe tomography have been performed on SiC, WC, Ti(C,N) and Ti 2 AlC grains in different materials as well as on large M 2 3C 6 precipitates in steel. Using standard evaluation methods, the obtained carbon concentration was 6-24% lower than expected from the known stoichiometry. The results improved remarkably by using only the 13 C isotope, and calculating the concentration of 12 C from the natural isotope abundance. This confirms that the main reason for obtaining a too low carbon concentration is the dead time of the detector, mainly affecting carbon since it is more frequently evaporated as multiple ions. In the case of Ti(C,N) andTi 2 AlC an additional difficulty arises from the overlap between C 2 + ,C 2+ 4 and Ti 2+ at the mass-to-charge 24 Da. © 2010 Elsevier B.V.

Författare

Mattias Thuvander

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Jonathan Weidow

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Jenny Angseryd

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Lena Falk

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Fang Liu

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Marie Sonestedt

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Krystyna Marta Stiller

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Hans-Olof Andrén

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Ultramicroscopy

0304-3991 (ISSN)

Vol. 111 604-608

Ämneskategorier

Analytisk kemi

Annan materialteknik

Styrkeområden

Materialvetenskap

DOI

10.1016/j.ultramic.2010.12.024