Titanium materials are characterized by high hardness, lightweight, and corrosion resistance. Due to these superior properties, titanium equipment is widely used in industrial, chemical, and other fields.

1.Corrosion Resistance and Mechanical Properties:

Titanium exhibits higher corrosion resistance than stainless steel and aluminum in many media, along with low density and high specific strength.

In air, oxidizing, or neutral aqueous media, titanium readily forms a dense titanium oxide passive film on its surface, shifting its electrode potential significantly positive and enhancing thermodynamic stability. The passivation coefficient (indicating chemical stability after passivation) is 0.18 for iron, 0.37 for nickel, 0.49 for molybdenum, 0.74 for chromium, 0.82 for aluminum, and 2.44 for titanium.

2.Low-Temperature Applications:

Titanium does not suffer from low-temperature brittleness like ferritic steels and can be used for cryogenic containers down to -269°C. However, due to the lower cost of austenitic stainless steel, aluminum, and copper for cryogenic applications, titanium is rarely used in stationary low-temperature containers. Instead, its high specific strength and lightweight make it suitable for mobile cryogenic containers in aerospace.

3.Chloride Media Resistance:

In chloride-containing media (e.g., seawater, brine), carbon steel, low-alloy steel, standard stainless steel, and aluminum exhibit poor corrosion resistance, while titanium demonstrates exceptional performance. Approximately 50% of titanium containers are used to resist chloride-induced corrosion.

4.Limitations in Reducing Media:

Titanium’s corrosion resistance relies on its surface oxide film, making commercially pure titanium and most titanium alloys unsuitable for strong reducing media like high-temperature hydrochloric acid. Ti-32Mo resists hydrochloric acid but has poor plasticity and workability, thus it is not standardized for pressure-processed titanium materials or included in container specifications.

5.Hazardous Media Avoidance:

Titanium may ignite, explode, or suffer stress corrosion in specific media, such as fuming nitric acid, dry chlorine gas, methanol, trichloroethylene, liquid N₂O₄, molten metal salts, and carbon tetrachloride. Titanium containers should avoid or use extreme caution with these media.

6.Combustion Risks:

Titanium combusts in pure oxygen above 500°C or in air above 1200°C. Titanium containers must not contact open flames in the presence of air or oxygen to prevent combustion.

7.Impact Toughness:

Titanium materials and containers generally do not require impact toughness evaluation.

8.Industrial Applications:

Titanium’s excellent corrosion resistance makes commercially pure titanium grades TA1 and TA2 the primary choice for over 90% of civilian industrial applications. Among titanium equipment, 75% are titanium containers, underscoring their critical role in China’s titanium industry.