The metals also resist most organics such as acetic acid and acetic anhydride as well as citric, lactic, tartaric, oxalic, tannic, and chlorinated organic acids. Relatively few metals besides zirconium can be used in chemical processes requiring alternate contact with strong acids and alkalis. However, zirconium has no resistance to hydrofluoric acid and is rapidly attacked, even at very low concentrations. Zirconium alloys can be machined by conventional methods, but they have a tendency to gall and work harden during machining. Consequently, tools with higher than normal clearance angles are needed to penetrate previously work-hardened surfaces.
Results can be satisfactory, however, with cemented carbide or high-speed steel tools.
Carbide tools usually provide better finishes and higher productivity. These metals can be formed, bent, and punched on standard shop equipment with a few modifications and special techniques. Zirconium has better weldability than some of the more common construction metals including some alloy steels and aluminum alloys. Low distortion during welding stems from a low coefficient of thermal expansion. Welding zirconium requires proper shielding because of the metal's reactivity to gases at welding temperatures.