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Atom Probe Tomography Analysis of TiCx Powders Synthesized by SHS in Al/Fe/Cu-Ti-C Systems.

ABSTRACT: The stoichiometry of titanium carbide (TiCx) particles is important in determining particle properties. Spherical TiCx powders with particle sizes of 1-5 ?m were produced by self-propagating high-temperature synthesis (SHS) in 30 wt.% Al-, 30 wt.% Cu-, and 30 wt.% Fe-Ti-C systems, respectively. To measure the compositions of the carbide powders, atom probe tomography (APT) tip specimens were carefully prepared by using a focus ion-beam milling method. APT analysis revealed that the TiCx particles formed in Al-, Cu-, and Fe-Ti-C systems are highly substoichiometric. The results are consistent with observations of the TiCx particles with a high content of oxygen and a certain amount of secondary metallic elements (Al, Cu, and Fe).

SUBMITTER: Jin S

PROVIDER: S-EPMC6947562 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Atom Probe Tomography Analysis of TiCx Powders Synthesized by SHS in Al/Fe/Cu-Ti-C Systems.

Jin Shenbao S Su Haokai H Sha Gang G

Materials (Basel, Switzerland) 20191207 24

The stoichiometry of titanium carbide (TiCx) particles is important in determining particle properties. Spherical TiCx powders with particle sizes of 1-5 μm were produced by self-propagating high-temperature synthesis (SHS) in 30 wt.% Al-, 30 wt.% Cu-, and 30 wt.% Fe-Ti-C systems, respectively. To measure the compositions of the carbide powders, atom probe tomography (APT) tip specimens were carefully prepared by using a focus ion-beam milling method. APT anal ...[more]

PMID: 31817923

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