Preparation Technology and Application of Spherical Titanium Powder

Spherical titanium powder and its alloys have low density, high specific strength, good heat resistance, corrosion resistance and other excellent properties, however, traditional titanium metallurgy has the disadvantages of long process cycle, large energy consumption and low utilization rate, and has broad application prospects in aerospace, shipbuilding technology, chemical industry, machinery manufacturing, cemented carbide and other aspects. The high cost and high price of titanium alloys limit their wide application. Therefore, reducing the cost of titanium and titanium alloys is an important means to further expand the application of titanium, then, let's understand the preparation technology and application of spherical titanium powder!

Spherical titanium powder clean forming, low energy consumption, material utilization rate and other advantages are expected to become one of the main development directions of titanium metallurgy industry in the future, in addition, titanium powder is also widely used as cast aluminum refiner, gas absorber, surface modifier of metal parts, magnesium aluminum alloy additive, raw materials for the manufacture of titanium compounds, etc. The quality and cost of spherical titanium powder is critical to the quality of its powder metallurgy products.

At present, there are many methods for preparing titanium powder at home and abroad, mainly including mechanical alloying, hydrodehydrogenation (HDH), atomization, metal thermal reduction and molten salt electrolysis.

The production process of spherical titanium powder

1. Mechanical alloying

Alloying refers to the metal or alloy powder in the high-energy ball mill due to the long-term violent impact and collision between the powder particles and the ball, so that the powder particles are repeatedly cold welded and broken, causing diffusion between powder atoms, the titanium compound or mixed powder and R&D medium (usually need to add a small amount of process control agent) into the high-energy ball mill (protected with argon) for grinding, so as to obtain the powder manufacturing process of the powder. When mechanically alloying to manufacture titanium and titanium alloy powders, alloy materials can be manufactured or single metal powders can be manufactured. The powder particles in the grinding are welded-broken-welded, and the advantage of this process is that the ground materials can be combined in any proportion.

2. Hydrodehydrogenation method

Hydrogenation hydrogenation method (HDH) is the use of titanium and hydrogen reversible characteristics of the preparation of titanium powder technology, the process to produce titanium powder particle size range, low cost, low requirements for raw materials, titanium absorption hydrogen after brittleness, mechanical crushing to prepare titanium hydride powder, under vacuum conditions high temperature hydrogenation to prepare titanium powder. At present, it has become the main method for the production of titanium powder at home and abroad, and in recent years, the research on the preparation of low-cost low-oxygen content titanium powder at home and abroad has become increasingly active. However, the content of titanium powder O and N produced by this method is high.

3. Atomization method

Atomization method refers to the flow of liquid metal or alloy broken into tiny droplets, at present, atomization method to prepare titanium powder mainly has gas atomization method and centrifugal atomization method, and then cooling and solidifying in the environment to obtain metal powder method.

3.1 Gas atomization method

The gas atomization method generally dissolves the raw materials in the crucible, and sprays the metal melt generated by high-speed gas from the nozzle at the bottom of the crucible in the form of a spray to condense it to form metal powder.

3.2 Centrifugal atomization method

When collecting titanium powder by centrifugal atomization method, at present, centrifugal atomization method mainly includes rotary electrode method (REP), plasma rotating electrode method, electron beam rotating disk method) EBRD ) and so on. The metal is broken by the centrifugal force generated by rotation, and after throwing out the mist-like droplets, it solidifies to obtain high-purity spherical titanium powder. And the powder particle size can be adjusted according to the speed of the rotating electrode. The titanium powder obtained by centrifugal atomization method is spherical, the surface is bright, dense, good fluidity, narrow particle size distribution, the powder prepared by rotary electrode technology is not common associated phase in atomized spherical titanium powder, the powder particle size is more uniform, but the titanium powder prepared by this method has a higher cost, compared with the powder prepared by gas atomization, it is currently widely used in the aerospace field.

4. Metal thermal reduction method

The traditional metal thermal reduction method for the preparation of spherical titanium powder mainly includes TiO2 calcium thermal reduction method and TiCl4 metal thermal reduction method. Magnesium reduction method to produce titanium powder is mainly sponge titanium production process of isoscopic titanium powder, due to the high content of impurity components, TiO2 calcium thermal reduction method is to use metal calcium at high temperature to reduce TiO2 to manufacture titanium powder; TiCl4 metal reduction methods include magnesium reduction method (Kroll method) and sodium reduction method (Hunter method). Titanium powder products specially used for the production of titanium powder have extremely low purity, especially oxygen, nitrogen, iron and carbon impurity.

5. Molten salt electrolysis method

Like other reactive metals, the electrolytic production of titanium powder needs to be carried out in a molten salt medium. However, due to the inability to control the reverse reaction of titanium and chlorine, it was aborted. At present, the Italian company Ginatta has established a large-scale pilot plant in the city of Turin to continue to study this technology, and the traditional molten salt electrolysis method is to dissolve titanium salt in molten salt. Dow-Howmet and Timet in the United States built two electrolysis lines respectively, and proposed the chlorination electrolysis method and fluorination method without diaphragm.

Application of titanium powder

1. Aerospace field

Titanium has been widely used in the aerospace field. Because titanium alloy has the characteristics of high strength, high heat resistance, specific strength and so on. Reducing the runway distance of aircraft takeoff/landing, titanium alloy can reduce the overall weight of the aircraft while improving the ability of the aircraft, improve the maneuverability, maneuverability and loading capacity of the aircraft.

With the improvement of China's national strength, the ability to protect maritime rights and interests is increasing, the number of carrier-based aircraft is also increasing, and the demand for titanium resistant to seawater corrosion will increase year by year.

2. Petrochemical field

Studies have shown that titanium alloys are still materials in high temperature and high pressure, high corrosive medium and high chlorine environment. The type of titanium is single, mainly using industrial pure titanium and TA10. The price of both titanium materials is very cheap, smelting technology, processing technology, welding technology are mature in China, the petrochemical field mainly uses titanium and titanium alloy corrosion resistance, the heat resistance requirements are not high, so compared with the titanium used in the aerospace field, so it can be used in large quantities in the domestic petrochemical field.

3. Marine engineering field

Titanium seawater corrosion and marine atmosphere corrosion are excellent, marine engineering is expected to become a new titanium people's livelihood market. In marine engineering, and the dissolution ions are very small, non-toxic, not polluted by the environment, well meet the application needs of marine engineering, the application of titanium in the field of marine engineering can not only reduce the quality of related equipment, but also reduce maintenance costs, titanium is mainly used in offshore oil and gas development, seaside real estate, coastal power plants, desalination devices, ships, marine fisheries, marine energy conversion, etc. Not only that, titanium has excellent low-temperature performance, prolonging the life of related equipment. For example, if the ship uses titanium, the equipment life can be extended to 30~40 years, but the magnesium-aluminum alloy, mild steel and other ships need maintenance for 10 years. It maintains a certain plasticity at -253, and the volume change in low temperature environment is small, which is suitable for icebreakers in the Arctic, etc.

The above introduction is the preparation technology and application of spherical titanium powder, if you need to know more, you can contact us at any time!