The Beryllium Thread

[Simplex3]

I'm putting this in here so that it won't hang around the top of the lounge while I cut and paste information in to post after post.

This is part of my ongoing offseaon attempt to get us ranked on the first page of some search engine(s) when nerds search for "beryllium".

Before you PM me with "Why?", the answer is simply that I am sitting around reading log files at work and cutting and pasting into this thread requires absolutely NO mental stress.

[2112]

In the United States, the average concentration of beryllium in the air is very low–about 0.03 nanograms (a nanogram is 1 billionth of a gram) in a cubic meter (Eco–USA: Beryllium). This figure increases to 0.2 nanograms per cubic meter in some cities because beryllium is released from burning coal and fuel oil. Individuals who live near an industry that processes or uses beryllium may be subjected to much higher beryllium levels. Those who live near hazardous landfill sites that contain high concentrations of beryllium may also be exposed to higher than normal levels of the element.

[Simplex3]

Beryllium is an alkali earth metal, reasonably stable in air, and extremely toxic in powdered form. It's used as an alloying element for copper, imparting great strength and springiness to the metal. Added to aluminum it makes light, strong, stiff alloys used in race cars and in aerospace applications. Solid lumps of beryllium left alone are not dangerous as such: It's not going to rub off and go through your skin, but because of its toxicity, care is needed when machining beryllium or its alloys.

[Simplex3]

Beryllium is an alkali earth metal, reasonably stable in air, and extremely toxic in powdered form. It's used as an alloying element for copper, imparting great strength and springiness to the metal. Added to aluminum it makes light, strong, stiff alloys used in race cars and in aerospace applications. Solid lumps of beryllium left alone are not dangerous as such: It's not going to rub off and go through your skin, but because of its toxicity, care is needed when machining beryllium or its alloys.

[Simplex3]

Beryllium oxide is worthy of special note because it is a good electrical insulator, but at the same time a good conductor of heat, which is a somewhat unusual combination. Metals generally conduct both heat and electricity well, while things like wood, rubber, etc, conduct both poorly: There aren't that many materials that do one but not the other. Beryllium oxide is used as a high-voltage insulator because it is able to conduct heat away from components while keeping them isolated electrically (see sample below).

[Simplex3]

Beryllium is a naturally occurring, silver-grey metal. Lighter than aluminum and more rigid than steel, Be has many unusual properties which make it ideal for several applications, including aircraft and space vehicle structure, x-ray machine assemblage, mirrors, ceramics, metal alloys, and, since the 1950's, nuclear technology including weapons and reactors.

[Simplex3]

The most significant disadvantage of Be as an industrial material appears to be the toxicity of its dust, fumes, and soluble salts. However, metallic Be has good resistance to alteration or chemical attack and is not easily altered to soluble forms when released to the environment. Most Be in the soils does not dissolve in water and remains bound to the soil particles.

[Simplex3]

An initiator is a device that produces a timed burst of neutrons to initiate a fission chain reaction in a nuclear weapon. Initiators made of polonium-210 and beryllium were located at the center of the fissile cores of early atomic weapons. The highly radioactive isotope of Polonium (Po-210) is a strong alpha emitter. Beryllium will absorb alphas and emit neutrons. This isotope of polonium has a half life of almost 140 days, and a neutron initiator using this material needs to have the polonium, which is generated in a nuclear reactor, to be replaced frequently. To supply the initiation pulse of neutrons at the right time, the polonium and the beryllium need to be kept apart until the appropriate moment and then thoroughly and rapidly mixed by the implosion of the weapon.

[Simplex3]

Beryllium is used as the reflector material (or 'pit liner') in most contemporary American nuclear weapons and thermonuclear primaries. The 'primary', or weapon trigger, consists of three components: the central spherical plutonium 'pit' or core, the Be 'pit liner', and a surrounding high-explosives shaped-charge. The pit liner, sometimes also referred to as the "skull", surrounds the spherical plutonium pit and is in turn surrounded by high explosives. All three of these components together make up a modern nuclear weapon's "primary", or trigger, which initiates the thermonuclear reaction in a weapon's secondary components. The beryllium liner effectively acts as 1) a reflector which directs neutrons back into the plutonium pit; 2) a tamper which initially contains and thereby helps to increase the force of the explosion; and 3) a generator of additional neutrons.2 A flux of neutrons at the beginning of a nuclear weapon's detonation initiates critical mass, which subsequently leads to the weapon's designed destructive yield.

[Simplex3]

The Department of Energy uses beryllium metal to fabricate weapons components and to facilitate a number of weapons-related experiments. Based on its analysis of the President's 2001 Nuclear Posture Review, the National Nuclear Security Administration (NNSA) estimated that it would need approximately 90 tons of beryllium metal to meet mission requirements over the next 30 years. About 50 tons of the material is currently available for purchase from the Defense Department's National Defense Stockpile. Because the only domestic producer of beryllium metal from ore ceased production in 2000, NNSA had been uncertai how it would overcome the perceived shortfall.

[Simplex3]

NNSA's existing beryllium metal weapon component manufacturing process involves machining down large blocks of beryllium metal so that only about four percent of the feed material ends up in the final product. This means that the process results in a discard of 96 percent of the material as scrap. Technical experts explained that this metal could not be reused for weapons production without reprocessing since it contains impurities from the manufacturing process. Near-net shaping, on the other hand, is a process by which beryllium powder is sized to a shape closer to that of the final parts, thereby allowing NNSA to use significantly less beryllium metal to manufacture the same parts.

[Simplex3]

Beryllium Is a Silver-Gray Metallic Element That Occurs Naturally in About 30 Minerals. Beryllium was discovered in 1798, but it was not widely used in industry until the 1940s and 1950s. In industrial applications beryllium can be:

[Simplex3]

* used as pure metal

[Simplex3]

* mixed with other metals to form alloys

[Simplex3]

* processed to salts that dissolve in water

[Simplex3]

* processed to form oxides and ceramic materials