As can be seen from the sketch of the study, the radioactive source can be shaped  into narrow beam source by the tungsten alloy collimator, when passing through the absorption medium, its strength will be weakened due to the interaction of both sides, and this phenomenon can be known as γ-rays absorbing. The absorption capacity of γ-ray is close to the density of the absorbing medium.It means that the density is higher, the atoms and electron of per unit volume is more,then the irradiating rate of γ-ray exposure rate will decay more and more rapidly.

As we all know, tungsten is the highest melting point, maximum density (twice than steel) material of all metals. Therefore, tungsten alloy as a γ-ray radiation shielding material is most suitable. Previously, large radiation shielding member was generally made of lead alloys. But as a radiation shielding member, lead has many malpractices, such as low melting point, poor hardness, and it’s easy to cause secondary bremsstrahlung and so on. Besides, lead is a heavy metal pollution source that could easily cause heavy metal poisoning. As a new radiation shield material, tungsten alloy radiation shielding material have many advantages compared to lead: 1, no secondary bremsstrahlung; 2, hardness; 3, good radiation shielding effect than lead under the same thickness; 4, good radiation resistance and corrosion resistance.

 

Since tungsten alloy has high density, strong anti-γ-ray capability, high strength, non-toxic in environmental protection and some other advantages, and it can greatly reduce the dose rate of photon with smaller thickness under a smaller environment, thus becoming the new researching and developing direction of ray-shielding materials.