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THORIUM - A NUCLEAR METAL AND ITS MANUFACTURING PROPERTIES

Thorium is another possible fuel and is free from phase changes below 1480*C. Thorium (90Th24) is also a radioactive metal like uranium and this can be converted into Uranium (92U234) by beta decay. The mechanical properties of thorium which is soft and weak when pure , are drastically changed by small addition of impurities. Only 0.2 per cent of carbon raises its tensile strength from 14 to 38 kg-f / mm2 (140 - 380 M pa). Small additions of  titanium, zirconium, and niobium decreases the strength and hardness of the metal. Uranium addition increases the strength of thorium.




Thorium like Uranium is an emitter of alpha rays and releases considerable quantity of the radioactive products during processing, but this being a cubic metal (fcc) is less susceptible to irradiation damage. The melting point of thorium is 1845*C.


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