Zirconium technically-pure materials

Ingots 15 mm in diameter and 80 mm in length (80-100 g weight) were arc-melted in a vacuum of 10 Pa. Iodine titanium, zirconium, technically pure aluminum and silicon were used as initial materials. 

Only two zirconium materials are standardised Zr 702 which is essentially technically-pure Zr and consists of the a phase only, and Zr 705 which contains 2 to 3 wt% Nb, has an O -I- microstructure and a higher yield stress. Their composition ranges and mechanical properties are listed in Tables 3.1-35 and 3.1-36. Since Hf is usually contained in the Zr ore zircon (ZrSi04) and is difficult to separate, the Zr materials are specified to contain Hf up to 4.5 wt%. The presence of Hf in Zr alloys up to this level of composition does not affect the mechanical and corrosion properties significantly. 

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