Jump to main content
Jump to site search


Assessment of PGAA capability for low-level measurements of H in Ti alloy

Abstract

Prompt gamma-ray activation analysis (PGAA) is a non-destructive nuclear analytical technique for quantitative determination of hydrogen concentration in solid matrices. The accuracy of low-level hydrogen measurements with PGAA depends on identifying and accounting for all background H signal, including interfering signals. At the cold-neutron (CN)PGAA facility at the NIST Center for Neutron Research, the sources of background H signal were investigated in the context of titanium-based matrices containing low-levels of H (< 300 mg H per kg Ti) with the measurements of prepared standards (mixtures of polyvinyl chloride and titanium oxide) and Ti alloy (Ti6Al4V) samples. The sensitivity ratio, defined as the ratio of the H signal to the Ti signal per unit mass ratio of H in Ti, was determined (1) with the measurements of prepared standards and (2) based on partial gamma-ray production cross sections and full-energy detection efficiencies. The resulting calibrations from these two approaches agreed within experimental uncertainty. A series of Ti alloy NIST Standard Reference Materials (SRMs) previously certified for H content (SRMs 2452, 2453, 2453a, 2454) were used as test cases, with the mass fractions determined based on the sensitivity ratios derived from method 1 and method 2, respectively. The results agreed with the certified values within experimental uncertainties, validating the analysis performed on the new instrument with newly-prepared standards at low H mass fractions (method 1), and with the standard-independent analysis (method 2). Various sample mounting improvements were made to lower the background H signal. Spectral interferences near the H peak were identified as potential sources of bias and as a limiting factor in the detection limit of H in Ti alloy samples.

Back to tab navigation

Publication details

The article was accepted on 29 Aug 2017 and first published on 07 Sep 2017


Article type: Paper
DOI: 10.1039/C7AN01308F
Citation: Analyst, 2017, Accepted Manuscript
  •   Request permissions

    Assessment of PGAA capability for low-level measurements of H in Ti alloy

    D. Turkoglu, H. Chen-Mayer, R. L. Paul and Z. R, Analyst, 2017, Accepted Manuscript , DOI: 10.1039/C7AN01308F

Search articles by author

Spotlight

Advertisements