properties
Uranium is a nonferrous, pure metallic element. Which has a density of 19.07gcm-3 this is 1.6 times denser than lead. The ultimate tensile strength varies with the type of uranium but ranges from 400MPa (in cast uranium) to 1150MPa (for wrought alpha phase uranium). The modulus of elasticity is 190GPa and the shear modulus is 86GPa, these do not vary with the type of uranium.
Some constants for uranium include the heat capacity 0.1156Jg-1ºC-1, the heat of fusion 50Jg-1, thermal conductivity 26.8Wm-1K-1 and the melting point 1132.3ºC. Other common factors include electrical resistivity 0.00003ohm cm and critical superconducting temperature 1.4K.
Radioactivity was discovered in 1896 by Henri Becquerel who noticed samples of uranium salt emitted invisible rays. These could penetrate through opaque materials and leave imprints on photographic plates. Later studies showed three kinds of radiation was emitted: alpha rays (the least penetrating), beta rays (more penetrating) and gamma rays (most penetrating).