Controlling residual hydrogen gas in mass spectra during pulsed laser atom probe tomography

Residual hydrogen (H(2)) gas in the analysis chamber of an atom probe instrument limits the ability to measure H concentration in metals and alloys. Measuring H concentration would permit quantification of important physical phenomena, such as hydrogen embrittlement, corrosion, hydrogen trapping, an...

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Detalles Bibliográficos
Autor principal: Kolli, R. Prakash
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Springer International Publishing 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5321712/
https://www.ncbi.nlm.nih.gov/pubmed/28280683
http://dx.doi.org/10.1186/s40679-017-0043-4
Descripción
Sumario:Residual hydrogen (H(2)) gas in the analysis chamber of an atom probe instrument limits the ability to measure H concentration in metals and alloys. Measuring H concentration would permit quantification of important physical phenomena, such as hydrogen embrittlement, corrosion, hydrogen trapping, and grain boundary segregation. Increased insight into the behavior of residual H(2) gas on the specimen tip surface in atom probe instruments could help reduce these limitations. The influence of user-selected experimental parameters on the field adsorption and desorption of residual H(2) gas on nominally pure copper (Cu) was studied during ultraviolet pulsed laser atom probe tomography. The results indicate that the total residual hydrogen concentration, H (TOT), in the mass spectra exhibits a generally decreasing trend with increasing laser pulse energy and increasing laser pulse frequency. Second-order interaction effects are also important. The pulse energy has the greatest influence on the quantity H (TOT), which is consistently less than 0.1 at.% at a value of 80 pJ.