Certification report - The certification of the gold mass fraction in Al-0.1%Au alloy: ERM®-EB530A, B and C

This report describes the production of ERM®-EB530A, B and C, aluminium gold alloy material certified for the mass fraction of gold. The material was produced following ISO Guide 34:2009. Pure aluminium and pure gold were arc melted together to obtain a master alloy Al-5%Au (mass percent). The master alloy was melted with pure aluminium in a resistance furnace, casted in ingot and heat treated. The ingot was processed mechanically (wire drawing or rolling) to obtain thin wire (diameter 0.5 mm and 1.0 mm) and thin foil (thickness 0.1 mm). Between-unit homogeneity was quantified and stability during dispatch and storage were assessed in accordance with ISO Guide 35:2006. Within-unit homogeneity was quantified to determine the minimum sample intake. The material was characterised by an intercomparison among laboratories of demonstrated competence and adhering to ISO/IEC 17025. Technically invalid results were removed but no outlier was eliminated on statistical grounds only. Uncertainties of the certified values were estimated in compliance with the Guide to the Expression of Uncertainty in Measurement (GUM) and include uncertainties related to possible inhomogeneity, and instability and to characterisation. The material is intended for the calibration of methods (k0-neutron activation analysis). As any reference material, it can also be used for control charts or validation studies. The CRM is packed in plastic boxes and available in three different versions: ERM-EB530A: foil of 50 cm2, thickness: 0.100 mm; ERM-EB530B: 1 meter of wire diameter 0.500 mm; ERM-EB530C: 1 meter of wire diameter 1.000 mm. The minimum amount of sample to be used is 0.55 mg. The CRM was accepted as European Reference Material (ERM®) after peer evaluation by the partners of the European Reference Materials consortium.JRC.D.2-Standards for Innovation and sustainable Developmen