Why is the Hafnium Used in Control Rods?
Posted by Cathie Montanez on October 12, 2019 8:30 AM EDT
Hafnium metal has excellent processing performance, which can be forged and drawn wire. The most important thing about hafnium is its nuclear properties.
Recently, the military industry and aircraft carrier concept stocks are very popular, while at present, only China, Russia, the United States, and France have the nuclear grade sponge zirconium. The construction of sponge zirconium and hafnium production line is the material base for the development of nuclear energy.
Hafnium metal has excellent processing performance, which can be forged and drawn wire. The most important thing about hafnium is its nuclear properties. Its thermal neutron absorption interface is as high as 115b (while zirconium is 0.18b), and there is good resonance absorption within the epithermal neutron absorption range. After fission, every generation product is hafnium. Hafnium is used in nuclear reactors without radiation, while silver-indium-cadmium has r-radiation, so it is very safe to use.
As hafnium metal has excellent nuclear, welding and processing properties, it's comprehensive the economic performance ratio is better than silver-indium-cadmium, so it is commonly used as a control rod for nuclear reaction, especially for water-cooled high-power long-life reactors. In the 1950s, the reactors of America's first nuclear-powered submarine used hafnium as control rods for the first time; in the 1980s, the United States used an average of 26 tons of hafnium per year for nuclear reactors, mainly for naval and aerospace purposes.
The niobium alloy, containing 10% of hafnium can be used as the nozzle of a moon landing rocket, while the tantalum-tungsten alloy, containing 2% of hafnium, has high creep strength and can be used as the protective layer material of spacecraft; hafnium metal powder can be used as material for rocket boosters; hafnium carbide (HfC) can be used as high-temperature structure material in the space field; the hafnium bomb, a small 5-inch hafnium bomb, is about 2, 000 tons of TNT, and has the explosive force of one-seventh that of the atomic bomb dropped on Hiroshima in 1945.
Stanford Advanced Materials supplies high-quality hafnium products to meet our customers' R&D and production needs. Please visit https://www.samaterials.com/ for more information.