The determination of oxygen in lead and its alloys

5 THE DETERMINATION OF OXYGEN IN LEAD AND ITS ALLOYS (PbCuTe, PbSnCd) 

All the analyses discussed below (221) were performed using a beam of 

It must be emphasized that the preparation of the samples and especially their etching after irradiation must be performed with extreme care. In addition, it is strongly recommended to remove a relatively thick layer ( 0.1 mm) from each side. Experience has shown that insufficient etching can lead to high results. 

In pure lead a concentration of (0.58 + 0.08) ig/g (n = 12) was determined. Before and after irradiation the samples were etched in a boiling mixture 

This procedure was also used to analyze another lead batch and two industrial alloys (PbCuTe and PbSnCd). However, to etch the samples, the foregoing solution was replaced by a mixture of 1 volume hydrogen peroxide and 3 volumes acetic acid. The etch is carried out at room temperature. Rinsings were performed with hot water (60 to 70°C) and the samples were dried in air as above. The melting temperature was significantly increased (1400 to 1500°C compared with 1250 C) and the bath (non-irradiated oxidized lead) was not changed. 

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