This titanium reference material certified for the mass fraction of elements was produced following ISO Guide 34:2009 and is certified in accordance with ISO Guide 35:2017.
Pure titanium was alloyed with the target elements to produce ingots that were subjected to vacuum arc re-melting. A powder was produced by the plasma rotating electrode (PREP) process, which was then turned into solid bars by hot-isostatic pressing. One part of the bars was cut into discs of a thickness of 2 cm (ERM-EB090a), the other part was cut into slices of 2 mm and chips of approximately 250 mg were punched out of these discs (ERM-EB090b).
Between unit-homogeneity was quantified and stability during dispatch and storage were assessed in accordance with ISO Guide 35:2017. The minimum sample intake was estimated on the basis of acceptable repeatability for results obtained by glow-discharge mass spectrometry (GDMS) and spark-optical-emission spectrometry (spark-OES). The material was characterised by an interlaboratory comparison of laboratories of demonstrated competence and adhering to ISO/IEC 17025:2017. Technically invalid results were removed but no outlier was eliminated on statistical grounds only.
Uncertainties of the certified values were calculated in accordance with the Guide to the Expression of Uncertainty in Measurement (GUM) and include uncertainties related to possible inhomogeneity, instability and characterisation. The materials are intended for the calibration of methods, quality control and assessment of
method performance. As with any reference material, they can be used for establishing control charts or in validation studies. The minimum amount of sample to be used is 50 mg.
keywords: metal analysis , industrial materials , Nonferrous metals , alloying elements, trace elements , direct solid sample analysis