Zirkoniumputkien edut ja käyttötarkoitukset
1. Material properties
Zirconium is a metal with excellent properties, and seamless zirconium tube inherits these properties.
Corrosion resistance: It has strong resistance to many chemicals, including acids, alkalis and salt solutions. In highly corrosive environments, such as chemical industry, marine engineering and other fields, seamless zirconium tubes can operate reliably and extend the service life of equipment.
High strength: It has high strength and hardness and can withstand large pressure and mechanical stress. This allows seamless zirconium tubes to maintain stable performance under harsh conditions such as high pressure and high temperature.
Good thermal conductivity: It can effectively transfer heat and play an important role in equipment such as heat exchangers.
Low neutron absorption cross section: In the nuclear industry, zirconium is widely used in structural materials and fuel cladding of nuclear reactors due to its low neutron absorption cross section.
2. Application field
Chemical industry: used to transport corrosive media such as strong acids and alkalis. Seamless zirconium tubes can ensure the safety and reliability of chemical production processes and reduce the cost of equipment maintenance and replacement.
Marine engineering: In the marine environment, seamless zirconium tubes can resist the corrosion of seawater and are suitable for facilities such as offshore platforms and submarine pipelines.
Medical field: Due to the good biocompatibility of zirconium, seamless zirconium tubes can be used to manufacture medical devices such as artificial joints and dental implants.
Nuclear industry: As the structural material and fuel cladding of nuclear reactors, seamless zirconium tubes play a vital role in the nuclear industry. It can ensure the safe operation of nuclear reactors and prevent nuclear leakage accidents.
3. Production process
The production of seamless zirconium tubes usually adopts the following processes:
Extrusion method: After the zirconium blank is heated to a certain temperature, it is extruded into a tube through an extruder. The seamless zirconium tube produced by this method has high dimensional accuracy and good surface quality.
Perforation method: First, the zirconium blank is made into a solid bar, and then a hole is punched in the center of the bar by a perforator to form a tube. Then subsequent processing and heat treatment are carried out to improve the performance of the tube.
Welding method: The zirconium sheet is rolled into a tube, and then the joints are welded by welding technology to form a seamless zirconium tube. This method is suitable for the production of large-diameter seamless zirconium tubes.
In short, seamless zirconium tubes have been widely used in many fields due to their excellent performance. With the continuous advancement of science and technology, the production process and performance of seamless zirconium tubes will continue to improve, providing more reliable material support for the development of various industries.
Zirconium tubes have the following advantages:
Excellent corrosion resistance: Zirconium exhibits excellent corrosion resistance in many acid and alkali media, and is very corrosion-resistant in most inorganic acids, organic acids, alkaline solutions, salt solutions and certain molten salts, and even in some harsh corrosive environments such as high-temperature, high-pressure water, steam and liquid metal. For example, in reducing acids such as sulfuric acid and hydrochloric acid, zirconium has excellent corrosion resistance, whiletitanium.html> titanium is relatively insufficient in this regard; the corrosion rate of industrial pure zirconium in all boiling hydrochloric acids of various concentrations is less than 0.025mm/a; it also has good corrosion resistance in sulfuric acid with a concentration not exceeding 70%. Its chemical stability is better than that of some base alloys, and stronger than advanced stainless steel, titanium and its alloys.
Good mechanical properties: Zirconium and zirconium alloys have moderate mechanical properties, such as good strength and plasticity, which can meet the requirements of mechanical properties of materials in various application scenarios.
Low neutron absorption cross section: In the nuclear industry, this characteristic makes zirconium alloys often used in nuclear fuel assemblies and in-core structures of water-cooled reactors, and are important nuclear materials.
Good thermal stability: In high temperature environments, zirconium tubes can maintain good stability, are not prone to deformation, strength reduction and other problems, and can be used for a long time under certain high temperature conditions.
Good processing performance: Zirconium and zirconium alloys have good plasticity and can be made into pipes, plates, bars and wires, among which pipes are the main products. Although the processing process is somewhat difficult, seamless zirconium tube products with high dimensional accuracy and good surface quality can be obtained through appropriate processing technology and technology.
Good weldability: Zirconium and zirconium alloys have good fusion welding performance. Commonly used welding methods include tungsten inert gas arc welding and electron beam welding, which facilitates the connection and assembly of seamless zirconium tubes in various structures and equipment.
Good surface quality: After proper processing and treatment, seamless zirconium tubes can obtain smooth and clean surfaces, which is conducive to use in some occasions with high surface quality requirements, such as in the medical field for the manufacture of implants.
Biocompatibility: In the medical field, zirconium has good biocompatibility and can be used to manufacture medical devices such as knee or hip joint implants. It has good adaptability to human tissue and will not cause serious rejection reactions and other problems.
Inhalation performance: Zirconium has a strong affinity with gas and can strongly absorb gases such as nitrogen, hydrogen, and oxygen. For example, when the temperature exceeds 900°C, zirconium can violently absorb oxygen and can be used as an absorbent.
What are the disadvantages of zirconium tubes?
High price: Zirconium is a relatively rare metal, and its extraction and processing process is complicated, resulting in a high production cost of seamless zirconium tubes, which in turn is expensive, which to a certain extent limits its wide application, especially in cost-sensitive fields.
Difficult processing: Zirconium has a special nature, with high melting point, high strength and high hardness, which makes the processing of seamless zirconium tubes difficult. The processing requires special equipment, processes and technologies, and has high requirements for manufacturers. The energy consumption and equipment loss during the processing are also large.
Limited high temperature performance: Although zirconium has certain strength and corrosion resistance at high temperatures, the performance of zirconium tubes may be affected at extremely high temperatures (such as exceeding a certain critical temperature), such as creep and strength reduction, which limits its application in certain extreme high temperature environments.
Hydrogen embrittlement problem: Zirconium is prone to hydrogen embrittlement under certain conditions (such as contact with hydrogen). Hydrogen embrittlement will reduce the toughness and ductility of zirconium tubes, making them brittle and prone to cracking, which seriously affects their service life and safety. When using seamless zirconium tubes in some environments involving hydrogen or where hydrogen may be produced, special attention should be paid to prevent hydrogen embrittlement.
High welding difficulty: The welding of seamless zirconium tubes requires special welding techniques and processes to ensure the welding quality and joint performance. If the welding process is improperly operated, welding defects such as cracks and pores are likely to occur, which will affect the overall performance and sealing of the zirconium tube.
What are the applications of zirconium tubes in the nuclear industry?
Nuclear fuel cladding tube:
Function: Nuclear fuel cladding tube is a strategic core material for the operation of nuclear power plants and the first barrier to ensure nuclear safety. It wraps the nuclear fuel to prevent the nuclear fuel from contacting the coolant and preventing the nuclear fuel from leaking outside the reactor.
Performance requirements: Zirconium tubes need to have good corrosion resistance, moderate mechanical properties, low neutron absorption cross-section and stability in high temperature and high pressure environments to ensure the safe packaging of nuclear fuel and the normal operation of the reactor. For example, zirconium tubes can remain stable in various corrosive media; under the high temperature and high pressure conditions of reactor operation, zirconium tubes will not easily deform, break or degrade in performance.
Core structural materials:
Function: Used to construct the internal structure of the core of a nuclear reactor, such as supporting fuel assemblies and guiding the flow of coolant. These structural components need to work stably for a long time under strong radiation, high temperature, high pressure and complex chemical environments.
Performance requirements: In addition to excellent corrosion resistance and high temperature stability, they also need to have sufficient strength and rigidity to withstand various loads and stresses inside the core. For example, during the operation of the reactor, the core structural material must be able to resist the scouring, vibration and various forces generated by the coolant and nuclear reaction, while maintaining its own structural integrity and stability to ensure the safe and reliable operation of the reactor.
Control rod assembly:
Function: The control rod is a key component for controlling the reactivity of the nuclear reactor. The control rod assembly is usually composed of control rods, connecting parts and drive mechanisms, among which the connecting parts and some structures may use zirconium tubes. By inserting and withdrawing the control rods in the reactor core, the number and energy distribution of neutrons can be adjusted, thereby realizing the start, stop and power regulation of the nuclear reaction.
Performance requirements: The zirconium tube needs to have good mechanical properties and corrosion resistance in the control rod assembly to ensure that it will not be damaged or fail during frequent actions. At the same time, since the control rod assembly will be affected by neutron irradiation and high temperature during the operation of the reactor, the zirconium tube also needs to have certain radiation resistance and high temperature stability to ensure that its performance and function can be maintained during long-term use.
Radiation protection device:
Function: During the operation of the nuclear reactor, a large amount of radiation will be generated, posing a potential threat to the operator and the surrounding environment. The main function of the radiation protection device is to effectively suppress and isolate radiation, protect the safety of operators, and reduce the impact of radiation on the surrounding environment.
Performance requirements: Zirconium tubes are an important part of radiation protection devices due to their high density and excellent radiation protection performance. It needs to be able to effectively block and absorb various radiation particles, such as alpha particles, beta particles, gamma rays, etc., and have a good radiation shielding effect. At the same time, in a long-term radiation environment, the radiation protection performance of the zirconium tube will not decrease significantly to ensure continuous and reliable protection.
