Quantitative analysis of zirconium alloys using borate fusion and wavelength dispersive X‐ray fluorescence spectrometry

Abstract

The National Institute of Standards and Technology uses borate fusion, wavelength dispersive X‐ray fluorescence (WDXRF) spectrometry and synthetic calibration standards for high performance, quantitative analyses of alloys reacted and partially dissolved for fusion into borate beads. Conversion from metal matrix to low Z glass preserves measurement sensitivity. Synthetic calibration standards closely match fused samples, yielding very low uncertainties in results. This approach was applied to zirconium alloys of ≥90% Zr and 17 elements: Al, Co, Cr, Cu, Fe, Hf, Mn, Mo, Nb, Ni, P, Pb, Sn, Ta, Ti, V, and W. To demonstrate capabilities, it was applied to Standard Reference Material (SRM) 360b Zirconium (Sn‐Fe‐Cr) Alloy, renewal SRM 360c, plus discontinued Zr alloy SRMs: 360, 360a, 1210 through 1215, and 1234 through 1239. Eleven elements exhibit biases ≤5% for these SRMs. Additional validation used comparative test methods of inductively coupled plasma (ICP) mass spectrometry, ICP optical emission spectrometry and prompt gamma‐ray activation analysis. This WDXRF method gives results of high enough quality to certify the valid elements in conjunction with results from one or more independent methods. Several phenomena complicate the approach. Normal Zr dissolution using HNO3 + HF, forms Zr(NO3)4 in solution and concentrates it on drying. Zr(NO3)4 sublimes at low temperatures, causing uncontrolled loss of Zr as the temperature exceeds 100°C. Rapidly heated Zr(NO3)4 may explode. Digestion with HF alone works well. High‐purity ZrO2 and LiF were used for matrix matching of calibration standards, requiring determinations of trace elements in the high‐purity ZrO2.

Atomic spectrometry update: review of advances in the analysis of metals, chemicals and materials

“…These results provide strong support to current models regarding cluster formation. Isotopes monitored were 58 Ni, 32 S and 51 V, at a medium resolution of 4000. The spectrometer was tted with a commercial micro-ow total consumption nebulizer mounted with a laboratory-made jacketed spray chamber whose temperature was set at 60 C. Large quantities of clusters were detected in Boscan crude and its toluene soluble and toluene insoluble subfractions both at room temperature and aer heating.…”

“…Another paper that utilised GPC-ICP-HRMS was presented by Garcia-Montoto et al 93 These authors also monitored 58 Ni, 32 S and 51 V to understand their removal in crude oil from atmospheric residues during hydrodemetallization and hydrodesulfurization. The Ni, S and V species size distributions were studied to track their evolution during the catalytic processes.…”

“…Quantitative analysis of zirconium alloys using borate fusion and WDXRF analysis of the glasses formed was described by Sieber et al 58 The alloys were prepared for analysis through the formation of lathe turnings that were 0.5–2 mm wide and 2–10 mm long. Approximately 0.5 g of these “chips” were weighed into 10 mL of water.…”