Titanium is a metallic element, gray, with an atomic number of 22 and a relative atomic mass of 47.87. Can be burned in nitrogen, high melting point. Titanium and Titanium-based alloy is a new type of structural materials, mainly for aerospace and marine industries.
Titanium has a density of 4.506-4.516 g / cm3 (20 ° C), a melting point of 1668 ± 4 ° C, a latent heat of fusion of 3.7-5.0 kcal / gatom, a boiling point of 3260 ± 20 ° C and a latent heat of vaporization of 102.5-112.5 kcal / Critical temperature 4350 ℃, critical pressure 1130 atm. Titanium thermal conductivity and poor conductivity, similar to or slightly lower than the stainless steel, titanium has superconductivity, titanium superconducting critical temperature of 0.38-0.4K. At 25 ℃, the heat capacity of titanium is 0.126 cal / g atom · degree, the enthalpy is 1149 cal / g atom, entropy is 7.33 cal / g atom · degree, the titanium metal is paramagnetic and the permeability is 1.00004.
Titanium has plasticity, high purity titanium elongation of up to 50-60%, cross-sectional shrinkage up to 70-80%, but the intensity is low, not suitable for structural materials. The presence of impurities in titanium, the mechanical properties of great influence, especially the gap impurities (oxygen, nitrogen, carbon) can greatly enhance the strength of titanium, significantly reducing its plasticity. The good mechanical properties of titanium as a structural material are achieved by the strict control of the appropriate impurity levels therein and the addition of alloying elements.