Beryllium.

beryllium The first air-resistant metal in the periodic table. As well as aluminum, it owes its stability to a durable film of oxide (BeO is generally a very inert substance, crucibles are made from it for melting rare earth metals, lithium and other substances that are very aggressive in the molten state). Since beryllium has a low density and a melting point higher than that of aluminum, it could be an excellent structural material if not for some of its properties. First, beryllium dust and all its compounds are extremely toxic. It, even in small doses, can cause the formation of malignant tumors (cancer). In addition, the technology of obtaining beryllium is quite complex due to the fact that it is highly dispersed in nature. This leads to the fact that the price of beryllium is quite high and in 1998, for example, was $ 800 per kilogram. This is about twice as high as silver.

The production of beryllium products has its own characteristics. They are produced by the method of powder metallurgy and sintering (cast products do not have sufficient strength). Also, beryllium is used to make beryllium bronzes (alloys of copper and 3-6% beryllium) - a material for springs that have a very high resistance to mechanical fatigue and do not give sparks during mechanical shocks. Beryllium bronzes are used, for example, to make tools for working in mines where there is a danger of gas explosion. Even beryllium bronze makes metal parts of golf clubs. Another application of beryllium, in nuclear engineering, is based on its high ability to slow down and reflect neutrons. Thus, beryllium was used to produce neutron reflectors for atomic bombs, which significantly reduce the critical mass of fissile material.