Zirconium is a chemical element with the symbol Zr and an atomic number of 40. Its elemental form is a high melting point metal and appears light gray. Zirconium is prone to forming an oxide film on its surface, which has a glossy appearance similar to steel. It has corrosion resistance and is soluble in hydrofluoric acid and aqua regia. At high temperatures, it can react with non-metallic elements and many metallic elements to form solid solutions.

Zirconium easily absorbs hydrogen, nitrogen, and oxygen; Zirconium has a strong affinity for oxygen, and oxygen dissolved in zirconium at 1000 ° C can significantly increase its volume. Zirconium is prone to forming an oxide film on its surface, which has a glossy appearance similar to steel. Has corrosion resistance, but is soluble in hydrofluoric acid and aqua regia. At high temperatures, it can react with non-metallic elements and many metallic elements to form solid solutions. Zirconium has good plasticity and is easy to process into plates, wires, etc. Zirconium can absorb a large amount of gases such as oxygen, hydrogen, and nitrogen when heated, and can be used as a hydrogen storage material. Zirconium has better corrosion resistance than titanium, approaching niobium and tantalum. Zirconium and hafnium are two metals with similar chemical properties, coexisting together and containing radioactive substances.

Zirconium is a rare metal with amazing corrosion resistance, extremely high melting point, ultra-high hardness and strength, and is widely used in aerospace, military, nuclear reactions, and atomic energy fields. The corrosion-resistant and highly resistant titanium products used on Shenzhou VI have much lower corrosion resistance than zirconium, with a melting point of around 1600 degrees. Zirconium has a melting point of over 1800 degrees, and zirconia has a melting point of over 2700 degrees. Therefore, zirconium, as an aerospace material, has greatly superior performance in all aspects compared to titanium.