Marine engineering materials are required to have unique properties, such as high strength, resistance to seawater hydrothermal corrosion, resistance to sulfidation corrosion, antimicrobial adhesion, and high toughness.
Titanium is light in weight, high in strength and resistant to corrosion. Particularly, it is immune to the erosion of saltwater or seawater and the marine atmospheric environment. It is a high-quality lightweight structural material and is called “marine metal”. Titanium has a wide range of uses in marine engineering and is particularly suitable for light marine equipment. It is one of the new key materials in the marine engineering field.
Low density, high strength, and high specific strength
The density of titanium is 4.51g / cm3, which is 57% of steel; the specific gravity of titanium is less than twice that of aluminum, and its strength is three times that of aluminum; the specific strength of titanium is the largest among commonly used industrial alloys. High specific strength can promote the miniaturization and lightweight of offshore equipment, increase the speed, buoyancy, and maneuverability of submarines, and increase the depth and payload of deep submersibles. Therefore, titanium is an essential key structural material for marine engineering.
Excellent corrosion resistance
Titanium is currently the best material resistant to the corrosion of seawater at normal temperatures. It has good corrosion resistance even in polluted seawater, hot seawater (less than 120 ° C), sea mud, flowing seawater. Its excellent corrosion resistance is due to its good self-passivation. When it is damaged to some extent, the surface oxide film or passivation film can quickly repair and recover itself. That is to say, titanium is almost non-corrosive in the ocean. The titanium surface has a strong and tough oxide film, so its corrosion resistance is better than other metals.
In the design of anti-corrosion equipment, the corrosion margin in the thickness direction of the load-bearing structural components can be greatly reduced, and the construction materials are greatly saved; the anti-corrosion equipment can be designed with the same life as the main body, reducing the frequency of maintenance, greatly reducing maintenance costs, and improving equipment service capabilities; titanium equipment does not require coating protection when used in the ocean, which simplifies the manufacturing process, shortens the construction period, and reduces the manufacturing cost.
Resistant to seawater erosion and cavitation
Most materials have a critical speed. Once this speed is exceeded, the surface oxide film will be washed away and the corrosion will accelerate. The corrosion resistance of titanium pipelines is much higher than that of copper and copper alloy pipes. The critical velocity of titanium in seawater is greater than 27 meters per second, and various erosion-corrosion tests have shown that titanium is very resistant to such corrosion. At the same time, cavitation resistance experiments show that titanium is one of the most resistant to cavitation damage.
High impact resistance
Titanium and titanium alloys have the best impact resistance, which is conducive to the ability of marine equipment to withstand the periodic impact of the waves and improve the safety and reliability of the equipment.
Titanium is non-magnetic and is ideal for applications where electromagnetic interference must be minimized. Titanium used in submarines can greatly reduce the submarine’s magnetic physics effect, thereby reducing its possibility of being discovered by antisubmarine aircraft’s magnetic detector; ships made of titanium can increase concealment and avoid being attacked by magnetic mines. In addition, titanium also helps improve the anti-magnetic interference ability of detection instruments and tools and ensures the accuracy of the signal.
High sound transmission coefficient
Titanium is used as the sonar shroud material for submarines and aircraft carriers, which can improve the sonar detection sensitivity and detection distance of the equipment, and improve the efficiency and safety of the equipment.
Excellent processing performance
Titanium has good machining performance, and can be made into practical engineering materials of various shapes and specifications, including titanium plates, titanium rods, titanium tubes, titanium wires, titanium foils, titanium forgings, etc.; Most titanium and its alloys have good weldability, and the strength coefficient of the weld can reach above 0.9; Titanium metal rarely generates delayed cracks after welding, and its equipment generally does not require post-weld heat treatment, which is beneficial to the construction of large-scale engineering equipment such as ships and marine engineering.
Titanium metal products have a long service life in the marine environment. After being scrapped, they can be disassembled and returned to the furnace, which can be processed into lower-grade titanium alloy materials for use, with minimal weight loss and high recovery.
Advanced Refractory Metals (ARM) is a leading manufacturer & supplier known predominantly for the core products Tungsten, Molybdenum, Tantalum, Rhenium, Titanium, and Zirconium. Headquartered in Lake Forest, California, ARM specializes in providing high-quality refractory metal products to customers from all over the world since 1994. Please visit https://www.refractorymetal.org for more information.
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