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α radiation source, with emitting alpha particles as its major characteristic, is a kind of source made up of alpha-emitting nuclides. The nuclides used for the preparation of α radiation source are 226Ra, 210Po, 228Th, 238pu, 244Cm, 24lAm and 242Cm. Alpha-emitting nuclides are toxic nuclides with long half-life and can emitα-particle spontaneously. The emitted α-particle could directly destroy the organ cells after it is inhaled or ingested by human to cause harm to human body. It is considered that chromosome damage from alpha particles is anywhere from 10 to 1000 times greater than that caused by an equivalent amount of gamma or beta radiation. Therefore,it is necessary to take effective measures to shield radiation released by the α-particle when using or preparing a α radiation source while not influence the efficiency of α radiation. The use of tungsten alloy α radiation source shielding is a effective measure.    

α radiation source has many applications. In general, the radioactive static eliminators employ an alpha emitting radioactive source, usually polonium-210, to ionize the air immediately in front of the device. The ions produced in the air are then attracted to the object that has the static charge. As a result of the collection of these ions by the object, the charge is reduced or eliminated. Radioactive static eliminator are particularly useful for flammable, explosive, fire ban environments, such as film, textiles, plastics, printing and dyeing, printing, electronics industry and other industries with serious electrostatic hazards. Another use of α radiation source is the ionization source of ion smoke alarm. Ion smoke alarm has an open external ionization chamber and a closed internal ionization chamber. The smoke-laden air get into the external ionization chamber before a fire to reduce the ionization effect ofα-particle, resulting in a unbalanced state of ionization current between the internal and external ionization chamber, then the electronic circuit zooms in on signals and raise the alarm. αradiation source also can be used as the ionization source of vacuum tubes, dew point meter, radioisotope heat engine and the check source for laboratory instruments and the like.

Though α radiation source is widely used in many fields, the radioactive substances with α particles produced by it in turn cause a threat to humans. So one can use the tungsten alloy α radiation source shielding to shield the α radiation source. High density tungsten alloy has high radiation shielding performance, so placing it around α source can effectively absorb and shield the α radiation.