Why are titanium and titanium alloys called marine metals?

- Dec 11, 2020-

The service environment of ships is a harsh oceanic climate. Due to prolonged contact with seawater, the hull and its equipment and components (such as high-temperature exhaust pipes, sea valves and pumps, propellers, etc.) are easily corroded, and protective measures are extremely It is cumbersome and difficult, so special technical requirements are put forward for ship materials:

titanium and titanium alloys

1. Good seawater corrosion resistance.

2. Good stability in high and low temperature environment

3. Safe and reliable, large load capacity, less maintenance or convenient maintenance, good workability such as bending and welding.

Advantages of titanium and titanium alloys as materials for ships

Titanium and titanium alloys, with their own excellent characteristics, almost meet all the requirements of marine materials, and can be called a near-perfect marine materials. The advantages are as follows:

1. Lightweight and high specific strength.

The density of titanium is 4.5g/cm³, which is higher than the density of aluminum at 2.7g/cm³ and lower than that of iron at 7.9g/cm³, which is only 57% of iron. Although the density of titanium is less than twice that of aluminum, its strength is three times that of aluminum. In industrial engineering applications, when selecting metals with higher specific strength, titanium alloys can be the preferred material. Under the same conditions, the deep diving vehicle made of titanium can reach a depth of 10,000 meters, while the deep diving depth of the steel deep submersible is far from reach. In addition, titanium has zero magnetism and will not be disturbed in any intensity of the magnetic field. Therefore, magnetic attack weapons such as torpedoes and torpedoes are used to attack the hull made of titanium alloy. The anti-custodial effect of this feature is favored by military engineering applications.

2. Good corrosion resistance in marine climate.

When the titanium alloy is in the air and some oxygen-containing media, due to the strong affinity between titanium and oxygen, a dense, strong adhesion and stable oxide film can quickly form on the surface, which is not easy to be damaged in many media , So as to protect the titanium matrix. Studies have shown that the corrosion rates of titanium and titanium alloys in the three waters of the South China Sea, the North Sea, and the East China Sea for 16 years are almost zero in either the full immersion zone, the tidal range, the splash zone or the marine climate. Therefore, the use of titanium alloys for ships can extend the service life on the one hand, and on the other hand can reduce the cost of protective treatment due to surface corrosion in the later period. 

3. Excellent comprehensive performance.

Titanium alloy can be processed by cold and hot forming, free forging, extrusion and welding, and has good processing adaptability. Data research shows that the impact toughness test of titanium alloys in the range of -60-20℃ does not have a brittle transition point. In addition, compared with aluminum alloy and steel, titanium alloy has the best heat resistance, low temperature resistance and fracture toughness.

JDSTEELPIPE is one of titanium alloys suppliers and manufacturers. If you want to know more about titanium alloys, contact us at info@jiade-group.com. Our customer specialists will be glad to help you.