“The prospects for the application of rare earths in the coating of steel products and metal products are very broad. The potential market is extremely huge. We should speed up R&D and promote the application of rare earth alloy coating technology to steel pipes, steel plates and special-shaped steel products.†This is a reporter recently in Ma'anshan Ding. When interviewed by Thai Rare Earth New Material Co., Ltd., the chairman of the company, Liu Yulu, and Chief Engineer Shi Zhimin, a professor-level senior engineer, elaborated their views.
Ma'anshan Dingtai Rare Earth New Material Co., Ltd. is a high-tech enterprise specializing in R&D and production of rare earth alloy coating technologies and products. It has independently developed rare earth multi-element alloy coatings and rare earth zinc aluminum alloy coating steel wire strands with independent intellectual property rights. Processes and technologies are widely used in construction projects such as power, telecommunications, and electrified railways.
According to the experts here, rare earth elements have a unique 4f electronic layer structure, large atomic magnetic moments, strong spin orbital coupling properties, and other elements in the formation of rare earth complexes, the coordination number can be in 3-12 It varies, and the crystal structure of rare earth compounds is also diverse. The unique physicochemical properties of rare earth elements show excellent mechanical properties when they are used to form intermetallic compounds and alloy materials with non-ferrous metals, which determines their extremely wide range of applications. Rare earths are widely used in traditional industries such as steel, iron, non-ferrous metals, machinery manufacturing, petrochemicals, etc. Rare earth non-ferrous alloy materials are a new generation of materials that are being developed in the modern aviation, aerospace, military, and automotive industries.
From the development history of hot-dip galvanizing technology all over the world, the hot-dip coating develops toward alloyed coatings and special plating technologies. In order to increase the service life of traditional iron and steel materials and products, the International Lead and Zinc Research Organization and Bethlehem Steel Corporation of the United States have developed Galfan, Galvalume and other new zinc-aluminum alloy anticorrosion coatings in the late 1980s. Product standards for production, and has been widely used. In China, the level of anticorrosive plating technology for steel materials and products is relatively backward, and the traditional galvanized layer accounts for more than 90% of the total amount of the country. The output of zinc-aluminum alloy coated steel products is very small, and the product quality is also unstable. There is still a gap between the ability and the international similar products.
Prior to the industrialization of rare earth multi-element alloy plating products, the development and application of the above-mentioned plating layers in the relevant technical fields in China are basically in the state of tracking research. Galvalume and Galfan coatings are superior to ordinary galvanized coatings in their corrosion resistance in the atmosphere, but their performance in soil and marine environments is not satisfactory. Therefore, the development of low-cost, cost-effective hot dip alloy plating is not only a development direction of hot dip plating technology, but also has very important practical significance.
To this end, Ma'anshan Dingtai Rare Earth New Material Co., Ltd. first developed a new type of anti-corrosion coating material—rare earth multi-element alloy coating material and process technology—in the country, overcoming the gas reduction method (Sendzimir method) of similar foreign products. Complex, expensive to manufacture, very demanding raw materials and a series of defects, and can use the domestic common "solvent method" process to achieve. The manufactured products have high corrosion resistance, excellent moldability, weldability and a series of good comprehensive properties, making full use of China's rich rare earth resources and easy promotion.
Afterwards, they also started to develop rare earth multi-element alloy I (RE-Zn-Al-Mg RE+Zn+Al+Mg), rare earth multi-element alloy II (rare earth-zinc-aluminum-magnesium-boron-chromium-titanium REZnAlMgBCrTi) and other plating technologies. product. Rare earth multi-element alloy I has excellent corrosion resistance and good electrochemical protection. The comprehensive corrosion resistance of the plating improves the rare earth alloy coated steel products to maintain good corrosion resistance under all kinds of harsh environments, thus effectively inhibiting the corrosion and destruction of steel products.
The rare earth multi-element II (rare earth-zinc-aluminum-magnesium-boron-chromium-titanium) plating technology and products listed in the national 863 plan are the characteristics of using the rare earth, zinc, aluminum and other metals to improve the fluidity of the plating solution, making the coating bright and beautiful. , Good finish, strong bonding, stable quality; At the same time, use trace elements such as RE, Mg, Ti, B, and Cr to suppress the grain boundary or intergranular corrosion characteristics to improve the ability of the coating to resist local corrosion. The surface of the coating is rich. Rare-earth oxides, aluminum-magnesium oxides and other anti-corrosion microstructures form a composite film that can effectively insulate the substrate and the corrosive medium, thereby slowing down the progress of electrochemical reactions and greatly improving the corrosion resistance of the coatings.
The plating material in various environments and corrosive media, the corrosion rate of the coating is lower than the current international corrosion-resistant zinc aluminum alloy coating material by more than 25%, the product manufacturing cost is reduced by more than 20%, and the corrosion resistance and service life of the product. It is more than 3 times that of ordinary galvanized coating. This technology is easy to popularize, and it is especially suitable for the actual equipment technology level of the iron and steel materials anti-corrosion processing industry in China at this stage.
According to experts, domestic rare earth zinc aluminum alloy coatings, rare earth multi-element alloy coating steel wire strand products, rare earth zinc aluminum alloy coating functional materials have good corrosion resistance and comprehensive technical performance. Industrial tests and inspections by national technical authorities confirmed that the technical performance indicators of related products are significantly higher than the technical requirements of current national standards for galvanized products. The important performance indicators of the products have exceeded the standards of the relevant products of the International Electrotechnical Commission (IEC) and the United States ASTM. The application of national key projects over the past few years can prove that, as a new type of rare earth functional material, the rare earth multi-element alloy coating can completely surpass the internationally popular Galfan alloy coating for the manufacture of various steel products.
The surface quality of the plated parts made of this material is excellent, which can meet the requirements of all kinds of steel products and high voltage and EHV transmission lines used overhead conductors and ground wire, power towers, lightning protection grounding wire and grounding net products resistant to salt spray and soil corrosion It is required that industrial production of the rare earth multi-element (REZnAlMgBCrTi) alloy plating functional materials has been realized. Research and development of rare earth multi-element (REZnAlMgBCrTi) alloy coating functional materials with international advanced level, the corrosion resistance and service life of the products made is 2-3 times that of ordinary galvanized anti-corrosion coating.
Compared with ordinary galvanized steel wire strand, rare earth zinc aluminum alloy coating, rare earth multi-element alloy coating steel wire strand product has the following remarkable features:
1. Appearance: The surface of rare-earth alloy coated steel wire strands is smooth and bright, with a certain degree of decorative appearance.
2, plating weight: This product overcomes the weakness of the general zinc aluminum alloy coating thickness, its alloy coating weight is higher than the national standard galvanized steel wire product technical requirements, and fully guarantee the product's service life.
3. Plating Adhesion: The adhesion between the rare earth alloy coating and the diamond core is good, and the coating adhesion itself winding test does not crack.
4, anti-corrosion: anti-corrosion ability, according to user requirements, the product can be neutral salt spray (NSS) test, sulfur dioxide (SO2) test, corrosion resistance than hot galvanized steel wire to increase 1-2 times.
5. Copper sulphate test: The number of steel copper sulfate tolerant tests is higher than the national standard for galvanized steel wire.
6, wire resistance: to meet the International Electrotechnical Commission (IEC) standards for steel core wire resistivity requirements, the index is better than the current national standards.
7. Matching with aluminum conductor: good material matching, because the steel wire substrate is plated with a continuous dense rare earth alloy coating material, can reduce the galvanic corrosion between the steel core wire and rare earth aluminum wire, aluminum wire, extend Steel core aluminum wire life.
8, the product's cost performance: The product has a higher quality and cost performance, can be compared (ie, slightly higher than) the price of hot-dip galvanized products to provide users with quality products.
Experts pointed out that although China has developed a new generation of rare earth alloy coating technology and materials, a number of key power construction projects in China, but due to limited production, far from meeting the needs of the domestic market. It is reported that in the 1980s, foreign patents for the successful development of the Zn-5%Al-Mild-Alloy Alloy Coating (GALFANTM) belonged to the International Lead-Zinc Organization (ILZRO). Since 1983, Zn-5%Al-Rich Alloyed steels (including plates, wires, and pipes) have been officially commercialized. So far, Zn-5%Al-Rich rare earth alloy coating has been patented in more than 30 countries in the world. 60 production lines worldwide have purchased patents for Zn-5% Al-Mild Metal Alloy Coating (GALFANTM) from (ILZRO) The license is for the production of Zn-5% Al-Rare Earth Alloy Plating (GALFANTM) plates, wires and pipes.
In 1996, a certain factory in China imported a full set of galvanized GALVAN® steel wire equipment with an annual output of 20,000 tons from foreign countries, and purchased a Galfan patent. However, due to various factors of cost and technology, the production line did not reach the normal level for a long time. Production put into operation.
A few years ago, a company also purchased imported full-plated GALFAN® steel wire equipment, and some enterprise-made equipment was put into production of GALFAN® steel wire. A smelter purchased a patent for the production of GALFANTM alloy ingots in the 1990s, but due to various For complicated reasons, GALFAN® steel wire has not been widely promoted in China.
The reason is that, in addition to plating GALVAN? Wire technology level, equipment and product manufacturing cost of product quality, China's market recognition and recognition of many factors, one of the important reasons is the foreign plating GALFAN? Steel wires and steel strands are incompatible with the actual productivity level and technological equipment capabilities of China's metal products industry. Therefore, plating GALFAN® steel wires and steel strands in China has not yet formed mainstream products in the market.
Industry experts believe that the new generation of rare earth alloy coating materials and technology, the application of steel on the prospects are extremely broad. The current application area only involves the power industry, mainly rare earth alloy coated steel wire and steel hinge wire, overhead conductors and ground wires for high-voltage and ultra-high voltage transmission lines, steel structures for power towers, lightning protection grounding wires and grounding nets, and cable trays. The application, and only in this area, China's annual demand for steel wire and steel hinge line reached 1 million tons, but now rare earth alloy coating production is only tens of thousands of tons, obviously can not meet the needs of the domestic market. The application of this high-tech technology to pipes, profiles, and plates has led to the development of rare-earth alloy coated steel pipes, rare-earth alloy coated steels, and rare-earth alloy plated products. The huge market for this is conceivable.
At present, most of our country still stays on galvanized steel pipes, galvanized steel plates and galvanized profiles. Basically, rare earth alloy plating technology is not used. Therefore, galvanized steel products and metal products have poor corrosion resistance, large pollution, and short service life. , does not meet the national policy of energy conservation and emission reduction.
Industry insiders proposed that the application of rare earth alloy plating technology in steel pipes, steel plates and special-shaped steels in China is fully qualified. Because China has abundant rare earth resources. That year, Deng Xiaoping once said that "there is oil in the Middle East, and rare earth in China." "We must do a good job of the rare earths to bring out the rare earth advantages of China." China's rare earth resources rank first in the world, and 154 million tons (REO) of rare earth mineral resources that have been explored have been explored globally, of which 89 million tons (REO) are in China, accounting for nearly 58% of global reserves. A complete production system has been established for analysis, detection, smelting, separation, and analysis. Has been able to produce more than 100 varieties, more than 200 kinds of specifications of rare earth products. In the past 20 years, China's rare earth smelting and separation industry has developed rapidly. Its variety, output, export volume, and consumption all account for the first place in the world, and it plays a decisive role in the world. It can be seen that China's abundant rare earth resources lay the foundation for the development of rare earth alloy coatings on steel products.
If the rare earth alloy coating technology is applied to steel pipes, steel plates, steel strips and profiles, the potential of the market is enormous. It is reported that Ma'anshan Dingtai Rare Earth New Material Co., Ltd. has extended the next step of R&D work to this broader field and developed new types of rare earth alloys on the tubes, plates, belts and profiles of rare earth alloy coatings. Plated steel, steel pipe and groove angle and other special-shaped steel.
Ma'anshan Dingtai Rare Earth New Material Co., Ltd. is a high-tech enterprise specializing in R&D and production of rare earth alloy coating technologies and products. It has independently developed rare earth multi-element alloy coatings and rare earth zinc aluminum alloy coating steel wire strands with independent intellectual property rights. Processes and technologies are widely used in construction projects such as power, telecommunications, and electrified railways.
According to the experts here, rare earth elements have a unique 4f electronic layer structure, large atomic magnetic moments, strong spin orbital coupling properties, and other elements in the formation of rare earth complexes, the coordination number can be in 3-12 It varies, and the crystal structure of rare earth compounds is also diverse. The unique physicochemical properties of rare earth elements show excellent mechanical properties when they are used to form intermetallic compounds and alloy materials with non-ferrous metals, which determines their extremely wide range of applications. Rare earths are widely used in traditional industries such as steel, iron, non-ferrous metals, machinery manufacturing, petrochemicals, etc. Rare earth non-ferrous alloy materials are a new generation of materials that are being developed in the modern aviation, aerospace, military, and automotive industries.
From the development history of hot-dip galvanizing technology all over the world, the hot-dip coating develops toward alloyed coatings and special plating technologies. In order to increase the service life of traditional iron and steel materials and products, the International Lead and Zinc Research Organization and Bethlehem Steel Corporation of the United States have developed Galfan, Galvalume and other new zinc-aluminum alloy anticorrosion coatings in the late 1980s. Product standards for production, and has been widely used. In China, the level of anticorrosive plating technology for steel materials and products is relatively backward, and the traditional galvanized layer accounts for more than 90% of the total amount of the country. The output of zinc-aluminum alloy coated steel products is very small, and the product quality is also unstable. There is still a gap between the ability and the international similar products.
Prior to the industrialization of rare earth multi-element alloy plating products, the development and application of the above-mentioned plating layers in the relevant technical fields in China are basically in the state of tracking research. Galvalume and Galfan coatings are superior to ordinary galvanized coatings in their corrosion resistance in the atmosphere, but their performance in soil and marine environments is not satisfactory. Therefore, the development of low-cost, cost-effective hot dip alloy plating is not only a development direction of hot dip plating technology, but also has very important practical significance.
To this end, Ma'anshan Dingtai Rare Earth New Material Co., Ltd. first developed a new type of anti-corrosion coating material—rare earth multi-element alloy coating material and process technology—in the country, overcoming the gas reduction method (Sendzimir method) of similar foreign products. Complex, expensive to manufacture, very demanding raw materials and a series of defects, and can use the domestic common "solvent method" process to achieve. The manufactured products have high corrosion resistance, excellent moldability, weldability and a series of good comprehensive properties, making full use of China's rich rare earth resources and easy promotion.
Afterwards, they also started to develop rare earth multi-element alloy I (RE-Zn-Al-Mg RE+Zn+Al+Mg), rare earth multi-element alloy II (rare earth-zinc-aluminum-magnesium-boron-chromium-titanium REZnAlMgBCrTi) and other plating technologies. product. Rare earth multi-element alloy I has excellent corrosion resistance and good electrochemical protection. The comprehensive corrosion resistance of the plating improves the rare earth alloy coated steel products to maintain good corrosion resistance under all kinds of harsh environments, thus effectively inhibiting the corrosion and destruction of steel products.
The rare earth multi-element II (rare earth-zinc-aluminum-magnesium-boron-chromium-titanium) plating technology and products listed in the national 863 plan are the characteristics of using the rare earth, zinc, aluminum and other metals to improve the fluidity of the plating solution, making the coating bright and beautiful. , Good finish, strong bonding, stable quality; At the same time, use trace elements such as RE, Mg, Ti, B, and Cr to suppress the grain boundary or intergranular corrosion characteristics to improve the ability of the coating to resist local corrosion. The surface of the coating is rich. Rare-earth oxides, aluminum-magnesium oxides and other anti-corrosion microstructures form a composite film that can effectively insulate the substrate and the corrosive medium, thereby slowing down the progress of electrochemical reactions and greatly improving the corrosion resistance of the coatings.
The plating material in various environments and corrosive media, the corrosion rate of the coating is lower than the current international corrosion-resistant zinc aluminum alloy coating material by more than 25%, the product manufacturing cost is reduced by more than 20%, and the corrosion resistance and service life of the product. It is more than 3 times that of ordinary galvanized coating. This technology is easy to popularize, and it is especially suitable for the actual equipment technology level of the iron and steel materials anti-corrosion processing industry in China at this stage.
According to experts, domestic rare earth zinc aluminum alloy coatings, rare earth multi-element alloy coating steel wire strand products, rare earth zinc aluminum alloy coating functional materials have good corrosion resistance and comprehensive technical performance. Industrial tests and inspections by national technical authorities confirmed that the technical performance indicators of related products are significantly higher than the technical requirements of current national standards for galvanized products. The important performance indicators of the products have exceeded the standards of the relevant products of the International Electrotechnical Commission (IEC) and the United States ASTM. The application of national key projects over the past few years can prove that, as a new type of rare earth functional material, the rare earth multi-element alloy coating can completely surpass the internationally popular Galfan alloy coating for the manufacture of various steel products.
The surface quality of the plated parts made of this material is excellent, which can meet the requirements of all kinds of steel products and high voltage and EHV transmission lines used overhead conductors and ground wire, power towers, lightning protection grounding wire and grounding net products resistant to salt spray and soil corrosion It is required that industrial production of the rare earth multi-element (REZnAlMgBCrTi) alloy plating functional materials has been realized. Research and development of rare earth multi-element (REZnAlMgBCrTi) alloy coating functional materials with international advanced level, the corrosion resistance and service life of the products made is 2-3 times that of ordinary galvanized anti-corrosion coating.
Compared with ordinary galvanized steel wire strand, rare earth zinc aluminum alloy coating, rare earth multi-element alloy coating steel wire strand product has the following remarkable features:
1. Appearance: The surface of rare-earth alloy coated steel wire strands is smooth and bright, with a certain degree of decorative appearance.
2, plating weight: This product overcomes the weakness of the general zinc aluminum alloy coating thickness, its alloy coating weight is higher than the national standard galvanized steel wire product technical requirements, and fully guarantee the product's service life.
3. Plating Adhesion: The adhesion between the rare earth alloy coating and the diamond core is good, and the coating adhesion itself winding test does not crack.
4, anti-corrosion: anti-corrosion ability, according to user requirements, the product can be neutral salt spray (NSS) test, sulfur dioxide (SO2) test, corrosion resistance than hot galvanized steel wire to increase 1-2 times.
5. Copper sulphate test: The number of steel copper sulfate tolerant tests is higher than the national standard for galvanized steel wire.
6, wire resistance: to meet the International Electrotechnical Commission (IEC) standards for steel core wire resistivity requirements, the index is better than the current national standards.
7. Matching with aluminum conductor: good material matching, because the steel wire substrate is plated with a continuous dense rare earth alloy coating material, can reduce the galvanic corrosion between the steel core wire and rare earth aluminum wire, aluminum wire, extend Steel core aluminum wire life.
8, the product's cost performance: The product has a higher quality and cost performance, can be compared (ie, slightly higher than) the price of hot-dip galvanized products to provide users with quality products.
Experts pointed out that although China has developed a new generation of rare earth alloy coating technology and materials, a number of key power construction projects in China, but due to limited production, far from meeting the needs of the domestic market. It is reported that in the 1980s, foreign patents for the successful development of the Zn-5%Al-Mild-Alloy Alloy Coating (GALFANTM) belonged to the International Lead-Zinc Organization (ILZRO). Since 1983, Zn-5%Al-Rich Alloyed steels (including plates, wires, and pipes) have been officially commercialized. So far, Zn-5%Al-Rich rare earth alloy coating has been patented in more than 30 countries in the world. 60 production lines worldwide have purchased patents for Zn-5% Al-Mild Metal Alloy Coating (GALFANTM) from (ILZRO) The license is for the production of Zn-5% Al-Rare Earth Alloy Plating (GALFANTM) plates, wires and pipes.
In 1996, a certain factory in China imported a full set of galvanized GALVAN® steel wire equipment with an annual output of 20,000 tons from foreign countries, and purchased a Galfan patent. However, due to various factors of cost and technology, the production line did not reach the normal level for a long time. Production put into operation.
A few years ago, a company also purchased imported full-plated GALFAN® steel wire equipment, and some enterprise-made equipment was put into production of GALFAN® steel wire. A smelter purchased a patent for the production of GALFANTM alloy ingots in the 1990s, but due to various For complicated reasons, GALFAN® steel wire has not been widely promoted in China.
The reason is that, in addition to plating GALVAN? Wire technology level, equipment and product manufacturing cost of product quality, China's market recognition and recognition of many factors, one of the important reasons is the foreign plating GALFAN? Steel wires and steel strands are incompatible with the actual productivity level and technological equipment capabilities of China's metal products industry. Therefore, plating GALFAN® steel wires and steel strands in China has not yet formed mainstream products in the market.
Industry experts believe that the new generation of rare earth alloy coating materials and technology, the application of steel on the prospects are extremely broad. The current application area only involves the power industry, mainly rare earth alloy coated steel wire and steel hinge wire, overhead conductors and ground wires for high-voltage and ultra-high voltage transmission lines, steel structures for power towers, lightning protection grounding wires and grounding nets, and cable trays. The application, and only in this area, China's annual demand for steel wire and steel hinge line reached 1 million tons, but now rare earth alloy coating production is only tens of thousands of tons, obviously can not meet the needs of the domestic market. The application of this high-tech technology to pipes, profiles, and plates has led to the development of rare-earth alloy coated steel pipes, rare-earth alloy coated steels, and rare-earth alloy plated products. The huge market for this is conceivable.
At present, most of our country still stays on galvanized steel pipes, galvanized steel plates and galvanized profiles. Basically, rare earth alloy plating technology is not used. Therefore, galvanized steel products and metal products have poor corrosion resistance, large pollution, and short service life. , does not meet the national policy of energy conservation and emission reduction.
Industry insiders proposed that the application of rare earth alloy plating technology in steel pipes, steel plates and special-shaped steels in China is fully qualified. Because China has abundant rare earth resources. That year, Deng Xiaoping once said that "there is oil in the Middle East, and rare earth in China." "We must do a good job of the rare earths to bring out the rare earth advantages of China." China's rare earth resources rank first in the world, and 154 million tons (REO) of rare earth mineral resources that have been explored have been explored globally, of which 89 million tons (REO) are in China, accounting for nearly 58% of global reserves. A complete production system has been established for analysis, detection, smelting, separation, and analysis. Has been able to produce more than 100 varieties, more than 200 kinds of specifications of rare earth products. In the past 20 years, China's rare earth smelting and separation industry has developed rapidly. Its variety, output, export volume, and consumption all account for the first place in the world, and it plays a decisive role in the world. It can be seen that China's abundant rare earth resources lay the foundation for the development of rare earth alloy coatings on steel products.
If the rare earth alloy coating technology is applied to steel pipes, steel plates, steel strips and profiles, the potential of the market is enormous. It is reported that Ma'anshan Dingtai Rare Earth New Material Co., Ltd. has extended the next step of R&D work to this broader field and developed new types of rare earth alloys on the tubes, plates, belts and profiles of rare earth alloy coatings. Plated steel, steel pipe and groove angle and other special-shaped steel.