Quantitative analysis of Nb in solution in a microalloyed carburizing steel by electrochemical etching
- Universidad Simon Bolivar, Valle de Sartenejas-Edificio MEM Piso 2, Departamento Ciencia de los Materiales, Caracas-1080 (Venezuela), E-mail: alrivas@usb.ve
- Advanced Steel Processing and Product Research Center, Colorado School of Mines, Golden, Colorado 80401 (United States), E-mail: dmatlock@mines.edu
- Advanced Steel Processing and Product Research Center, Colorado School of Mines, Golden, Colorado 80401 (United States), E-mail: jspeer@mines.edu
The amount of Nb in solution in a microalloyed carburizing steel (Nb-modified SAE 8620) was evaluated in different heat treated conditions. The test procedure involved electrochemical extraction, filtration and Inductively Coupled Plasma Atomic Emission Spectroscopic (ICP-AES) analysis. Characterization by X-ray diffraction of the residues collected in the filters was also performed. Results showed that Nb in solution tends to hydrolyze during electrolysis in a 10 vol.% HCl electrolyte, giving misleading measurements of the amount of Nb that dissolved during high temperature heat treatment. Hydrolysis of Nb is prevented by the addition of tartaric acid to the electrolyte. In the full dissolution condition, coarse (Ti,Nb)CN was the only precipitate present. Finer (Nb,Ti)C precipitates were observed after heat treating at 1050 deg. C.
- OSTI ID:
- 21062228
- Journal Information:
- Materials Characterization, Vol. 59, Issue 5; Other Information: DOI: 10.1016/j.matchar.2007.04.015; PII: S1044-5803(07)00160-X; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 1044-5803
- Country of Publication:
- United States
- Language:
- English
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