Hafnium Alloy Tubes and Pipes
Hafnium Alloy Tubes and Pipes
Hafnium is a lustrous, silvery-gray transition metal. Hafnium is so chemically similar to zirconium that separating the two elements is extremely difficult. Most commercial hafnium is produced as a byproduct of zirconium refining. Hafnium is remarkably corrosion-resistant and an excellent absorber of neutrons, allowing its use in nuclear submarines and nuclear reactor control rods — a critical technology used to maintain fission reactions while preventing them from accelerating beyond control. Hafnium is also used in electronic equipment such as cathodes and capacitors, as well as in ceramics, photography flash bulbs, and light bulb filaments.
| Specification and Standard for Hafnium Alloy Tubes and Pipes | |||
| Products | Grades | Size | Standards |
| Hafnium Alloy Seamless Tube / Pipe Hafnium Alloy Welded Tube / Pipe | Zirconium 702 (R60702) Zirconium 704 (R60704) Zirconium 705 (R60705) Zircaloy-2 (R60802), Zircaloy-4 (R60804) | Seamless Tube OD: 0.6–89 mm Welded Tube OD: ≥89 mm Wall Thickness: ≥0.2 mm Length: 100–12000 mm | ASTM B658/B658M ASTM B523/B523M ASTM B353/B353M |
| Testing Provided for Hafnium Alloy Tubes and Pipes | ||||
| Chemical Composition | Mechanical Properties Test | Ultrasonic Test | Flattening | Flaring |
| Eddy Current Test | Dimensional Inspection | Ultrasonic Flaw Detection | Bending Test | — |
| UNS | Grade | Zr + Hf (min %) | Hafnium (max %) | Fe + Cr (max %) | Tin (%) | Hydrogen (max %) | Nitrogen (max %) | Carbon (max %) | Niobium (%) | Oxygen (max %) |
| R60702 | Zr702 | 99.2 | 4.5 | 0.2 max | — | 0.005 | 0.025 | 0.05 | — | 0.16 |
| R60704 | Zr704 | 97.5 | 4.5 | 0.2–0.4 | 1.0–2.0 | 0.005 | 0.025 | 0.05 | — | 0.18 |
| R60705 | Zr705 | 95.5 | 4.5 | 0.2 max | — | 0.005 | 0.025 | 0.05 | 2.0–3.0 | 0.18 |