2014-05-30

Tungsten Alloy Tube for Radiation Shielding

Tungsten Alloy are more useful for detecting beta particles and gammas. Most counters cannot detect alpha particles. Remember that alpha particles are easily shielded. For this reason, tungsten alloy tube has to be made with a special window, or else the window itself will block the alpha particles and they won't be detected. Secondly, the counter must be held steady for several seconds at the same distance in order for us to obtain a good reading. Moving the counter around will change the number of particles that enter the tube; so make sure that you hold the tube the same distance from each object that you are trying to measure, or else your results will not be accurate. A third disadvantage of a Geiger counter is that it cannot measure very high amounts of radiation; in fact, the machine can be damaged if you expose it to an extremely high radiation, but that is unlikely in our case.


Different Radiations

Here are many different radiations in our life:

An alpha particle (a) consists of two protons and two neutrons (a helium nucleus). It has a relatively large mass and a positive charge. Alpha particles are easily shielded by a piece of paper or human skin. Therefore, health effects of alpha exposure occur only when the particles are inhaled, ingested, or enter the body through a cut in the skin. More serious would be a material that is radioactive (a emitter) that is ingested into the body. The a particles emitted inside the body, for example in bone marrow, can be exceedingly dangerous.

Beta particles (b) are fast electrons produced following nuclear decay of certain radioactive materials. The amount of energy (speed) that a beta particle contains determines its penetrating capacity. Six millimeters of aluminum are needed to stop most b particles.

Gamma rays (g), an electromagnetic wave, are similar in form to visible light and radio waves. However, gamma waves are very energetic and have a far shorter wavelength. Gamma rays are produced from radioactive decay, in nuclear reactions, and in fission. Gamma rays are dangerous because they have great penetrating ability. Several millimeters of lead are needed to stop gamma rays.

Therefore, radiation protection is more and more important, for more details, you should visit radiation protection.

How Does Lead Absorb Radiation Like X-rays and Gamma Rays?

The reason that lead is a good choice is because it’s a very dense substance, because dense substances can get in the way of the radiation and soak it up.  And the denser something is the more atoms, and in the case of things like x-rays and gamma rays the more electrons, there are to potentially interact with that ray as it goes through and stop it.

So, if you look at the density of lead; lead weighs something like 11 grams per centimeter cubed.  Iron, on the other hand, is only seven.  So in other words, you can get lots and lots of shielding with lead for much less space than if you use, say iron or concrete, which doesnt have the same density, although both could soak up x-rays in the same way.

However, as tungsten alloy material is more than 60% denser than lead, and it's not of any toxic, tungsten alloy material is widely used for shielding of X-rays and gamma rays. For more details, you could visit tungsten alloy radiation shielding.


2014-04-25

Gamma Rays Absorbed by High Density Material

Gamma rays are better absorbed by materials with high atomic numbers and high density, such as tungsten alloy material. Although neither effect is important compared to the total mass per area in the path of the gamma ray. For this reason,lead shield is only modestly better (20–30% better) as a gamma shield, than an equal mass of another shielding material such as aluminium, concrete, water or soil, lead's major advantage is not in lower weight, but rather its compactness due to its higher density. Therefore, tungsten alloy material is better in its high density,good radiation absorption, etc.

Read more: http://www.tungsten-alloy.com/en/alloy07.htm


Tungsten and Radiation

Hey guys, I'm studying in physics recently.

Okay, here's my idea: We use lead to protect us from gamma radiation because it's dense enough to somewhat absorb the tiny wave length.
As I take it, tungsten is more dense than lead, right? Wouldn't it be safer to use tungsten instead of lead? (Looking away from the price aspect, of course...)


Read more: http://www.tungsten-alloy.com/en/alloy07.htm


2014-04-22

Tungsten Alloy Radiation Parts

Tungsten alloys are used for radioactive source containers, gamma ray protection, radiation shields, x-ray shielding and source holders for oil-well, logging, and industrial instrumentation.

A particularly dense material with excellent shielding properties is needed to ensure that the surrounding tissue is protected and the radiation guided only to the intended locations--High density tungsten alloys are widely used as Medical and Industrial Radiation Shielding.

Chinatungsten's tungsten alloys are used for radioactive source containers, which can to be made as collimator and shielding for cancer therapy machines, and as syringe protection for radioactive injections.


There is no licensing required for tungsten alloy materials. Tungsten alloys are stable at high temperatures.


Non-Radioactive Tungsten Materials

Two significant alternative, non-radioactive tungsten materials have been developed. The first one, introduced in the 1980's, is most commonly available as 2% ceriated tungsten. This material is commonly used for lower amperage DC welding applications. In fact, it holds a very high market share in sales for the orbital welding process.

More recently, 1½% lanthanated tungsten has emerged as what could be the future standard for tungsten electrodes. The 1½% by weight content (as opposed to 2%) was chosen by three of the largest manufacturers as the optimum content amount based on scientific studies which showed that this content amount most closely mirrors the conductivity characteristics of 2% thoriated tungsten. Therefore, welders can usually easily replace their radioactive 2% thoriated material with this tungsten and not have to make any welding program changes. In addition, since the lanthanum oxide material is less dense that thorium oxide, a stick of 1½% (by weight) lanthanated tungsten actually contains 15% more oxides by volume than a stick of 2% (by weight) thoriated tungsten. This aids in arc starting and stability, as well as longevity, because the additional volume of oxides keep the tip cooler.


Finally, 1½% lanthanated tungsten is suitable for both AC and DC welding applications. Therefore, facilities that stock both 2% thoriated tungsten for DC welding and another tungsten type (usually pure or zirconiated tungsten) for AC welding, could stock only one tungsten type.