The density of titanium is 4.5g / cm3, which is 57% of steel; titanium is less than twice heavier than aluminum and three times stronger than aluminum. Specific strength is the ratio of strength to density. When compared with different materials, the specific strength of titanium alloys is almost the largest among commonly used industrial alloys. The specific strength of titanium alloy is 3.5 times that of stainless steel, 1.3 times that of aluminum alloy, and 1.7 times that of magnesium alloy, so it is an indispensable structural material for the aerospace industry. Comparison of the density and specific strength of titanium with other metals. Titanium has a high melting point, poor thermal conductivity and electrical conductivity, and is similar to or slightly lower than stainless steel. Titanium has superconductivity, and the critical temperature of pure titanium is 0.38.4K. Metal titanium is a non-magnetic substance.
Titanium alloy is a “single-phase alloy composed of phase solid solution, with low density, whether it is at a general temperature or at a higher practical application temperature, it is a phase, the structure is stable, the wear resistance is higher than pure titanium, and the oxidation resistance Strong. Under the temperature of 500-600 degrees, it still maintains its strength and creep resistance, can be strengthened by heat treatment, has good thermal strength and thermal stability, good welding performance, good room temperature, ultra-low temperature and high temperature performance.
Commercial pure titanium (commercial pure titanium) is a dense metal titanium with a titanium content of not less than 99% and containing a small amount of impurities such as iron, carbon, oxygen, nitrogen and hydrogen. The impurities with the strongest influence on the mechanical properties of pure titanium are oxygen, nitrogen and iron, especially oxygen. The reaction of hydrogen with titanium is reversible. The effect of hydrogen on the performance of titanium is mainly represented by “hydrogen embrittlement”. Usually, the hydrogen content should not exceed 0.015%, and generally contain 0.15% -0.3% oxygen and 0.03% -0.05% nitrogen. Although industrial pure titanium is a close-packed hexagonal lattice at room temperature, its axis is relatively small (c / a = 1.587), which has better workability. Pure titanium has good formability and welding performance, and is not sensitive to heat treatment.