Nanotec Metals Division (NMD), headquartered in Lakeland, Florida, is an established supplier of the neutron absorber material Metamic®, and its nanotechnology-based high strength cousin, Metamic-HT.

Nanotec Metals Division Offices

In the late 1990s, Metamic® emerged to become the nuclear power industry’s definitive solution to the age-old problem of neutron absorber performance. The mechanical properties of Metamic have fueled its use to rehabilitate spent fuel storage racks with malperforming neutron absorbers and propelled its use in the latest generation of high-density fuel storage racks. All active cask designers have sought (and some have already received) the NRC’s approval to equip their fuel baskets with Metamic. Metamic is being used virtually exclusively in the U.S. in wet storage applications to avert the physical stability problems of the old generation neutron absorbers.

Tom Haynes: Executive-in-charge

Conceived and developed in the Reynolds Metal Company’s research laboratories, Metamic was tested ad nauseam for its adequacy by the Electric Power Research Institute in the late 1990s and subsequently by cask system designers. Holtec International conducted a 4 year testing program ending in 2003 and incorporated Metamic in the company's wet and dry product lines. Metamic is a fitting symbol of American ingenuity and an apt affirmation of the adage, “necessity is the mother of invention”.

In addition to serving as the ultimate device to ensure reactivity control whether in a plant’s fuel pool, in a dry storage cask, or in the long-term repository, Metamic also holds out the promise to become a preferred material in the aircraft, automobile, and other industries where a high strength-to-weight ratio, good ductility and weldability (all strong points of Metamic are considered premium material attributes.

Brief Summary of the METAMIC® HT Technology Development

Conventional aluminum alloy metallurgy is based on the addition of high solubility elements such as Cu, Mg, Zn, Si, etc which form intermetallic compounds to improve the mechanical properties of pure aluminum. These high solubility elemental compounds are put into solid solution through solution heat treatment followed by natural or artificial aging at a temperature range between 275° - 375°F.

If these conventional aluminum alloys are exposed to the artificial temperature range or higher temperatures for an extended period of time – the alloy continues to precipitate these intermetallic compounds thus losing the strength and hardness of the aluminum alloy system. Due to this phenomenon high strength aluminum alloys have been used extensively at ambient or limited to low temperature applications. Material scientists continue to develop new technology’s to increase the operating temperature of aluminum and its alloys because of the low density and high corrosion resistance characteristics of the material.

METAMIC® HT is a high temperature aluminum base material which utilizes Holtec's patented powder metallurgy technology to produce an extremely fine grained nano particle alumina reinforce matrix alloy with boron carbide particulate addition to form a metal matrix composite alloy system.

Metamic-HT has excellent physical properties at elevated and cryogenic temperatures, including creep resistance, yield strength, tensile strength and fracture toughness. In August 2009, Metamic-HT became the first nanotechnology based material to win USNRC's acceptance as the dual function material (structural and neutron absorption) for use in the fuel basket of a transport cask (Docket No. 71-9325).

METAMIC® HT aluminum boron carbide metal matrix composite material can be supplied in a wide variety of shapes such as hexagon, square, and round hollow tube profiles using our patented extrusion technology.