Moving Forward Every Day — 2010.03.6
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This post was last edited by mopeizhi on 2010-3-7 at 14:57. Moving forward every day – we hope that those who wish to participate can learn and improve from it every day: Why is titanium alloy sometimes needs to be anodized? How is anodization achieved? This topic welcomes active discussions from all members, so that those who already know can reinforce their knowledge and those who don’t can improve theirs, thereby achieving the goal of learning together and improving together.
Answer: Titanium alloys possess excellent properties such as good chemical stability, high specific strength, and the ability to maintain their strength even at temperatures ranging from 400 to 500°C; as a result, they have become new types of structural materials widely used in the chemical industry and the aerospace industry. However, the problem with chin alloy in applications is that it tends to cause galvanic corrosion in other materials when in contact with them, and it is prone to scratching and corrosion under moderate to high loads. A way to overcome these practical difficulties is to alter the surface properties of brass alloys, and anodic treatment is considered an effective and simple method for this purpose. There are numerous patent reports on the anodization of brass alloys, and recommended electrolytes include various solutions such as sulfuric acid, organic acids, nitrates, and caustic alkalis. It can be seen that Chinn alloy readily forms a film through anodization in acidic, neutral, and alkaline electrolytes. However, the thickness of the membrane is mostly confined to the range of 0.1–0.2 mm. Within this thickness range, the surface of the film exhibits various colors due to light interference, which is why it is called an interference film. Obtaining a thicker anodized film required for engineering applications is still an issue under development. Manty et al. proposed a production process that is said to have been successfully applied in aviation engines. The recommended composition of the electrolyte is as follows: 100 g/L of trisodium phosphate, 70 mg/L of hydroxide, 70 mg/L of phosphoric acid, with a pH of 7.0–8.0. The operating temperature of the solution is 25–55°C; a uniform film cannot be formed when the temperature is below 25°C. If the temperature exceeds this upper limit, the film becomes loose, porous, and has low hardness. To dissipate the heat accumulated during the process, stirring measures can be taken. Anodization uses a half-wave rectifier power supply; when current is applied to the workpiece, the voltage rises rapidly to the desired value, and due to the formation of a film, the current then drops sharply. Thereafter, the process needs to rely on gradually increasing the voltage to continue. The rate at which the voltage increases is determined by the decrease in current. China’s aviation industry has successfully developed thick-film anodization, which has been put into use.
Titanium alloys possess excellent properties such as good chemical stability, high specific strength, and the ability to maintain their strength even in environments with temperatures ranging from 400 to 500°C; as a result, they have become new types of structural materials widely used in the chemical industry and the aerospace industry. However, the problems associated with titanium alloys in practical applications are that they can cause galvanic corrosion in other materials when in contact with them, and they are prone to scratching and corrosion under moderate to high loads. A way to overcome these practical difficulties is to alter the surface properties of titanium alloys, and anodic treatment has been found to be an effective and simple method for this purpose. There are numerous patent reports on the anodization of titanium alloys, and recommended electrolytes include various solutions such as sulfuric acid, organic acids, nitrates, and caustic alkalis. It can be seen that titanium alloys can easily form a film through anodization in acidic, neutral, and alkaline electrolytes. However, the thickness of the film is generally confined to the range of 0.1–0.2 mm. Within this thickness range, the surface of the film exhibits various colors due to light interference, which is why it is called an interference film. The operating temperature of the solution is 25–55°C; a uniform film cannot be obtained when the temperature is below 25°C ； If the temperature is above the upper limit, the membrane becomes loose and porous with low hardness. To dissipate the heat accumulated during the process, stirring measures can be taken. Anodization uses a half-wave rectified current; when the component is placed in the tank and the current is applied, the voltage rises rapidly to the desired level. Due to the formation of a film, the current then drops sharply. Thereafter, the process must continue by gradually increasing the voltage. The rate at which the voltage is increased is determined by the rate of decline of the current. China’s aviation industry has successfully developed thick-film anodization, which is now in use.
Titanium alloys possess excellent properties such as good chemical stability, high specific strength, and the ability to maintain their strength even in environments with temperatures as high as 400–500°C; as a result, they have become new types of structural materials widely used in the chemical industry and the aerospace industry. However, the problem with chin alloy in applications is that it tends to cause galvanic corrosion in other materials when in contact with them, and it is prone to scratching and corrosion under moderate to high loads. A way to overcome these practical difficulties is to alter the surface properties of brass alloys, and anodic treatment is considered an effective and simple method for this purpose. There are numerous patent reports on the anodization of brass alloys, and recommended electrolytes include various solutions such as sulfuric acid, organic acids, nitrates, and caustic alkalis. It can be seen that Chinn alloy readily forms a film through anodization in acidic, neutral, and alkaline electrolytes. However, the thickness of the membrane is mostly confined to the range of 0.1–0.2 mm. Within this thickness range, the surface of the film exhibits various colors due to light interference, which is why it is called an interference film. Obtaining a thicker anodized film required for engineering applications is still an issue under development. Manty et al. proposed a production process that is said to have been successfully applied in aviation engines. The recommended composition of the electrolyte is as follows: 100 g/L of trisodium phosphate, 70 mg/L of hydroxide, 70 mg/L of phosphoric acid, with a pH of 7.0–8.0. The operating temperature of the solution is 25–55°C; a uniform film cannot be formed when the temperature is below 25°C. If the temperature exceeds this upper limit, the film becomes loose, porous, and has low hardness. To dissipate the heat accumulated during the process, stirring measures can be taken. Anodization uses a half-wave rectifier power supply; when current is applied to the workpiece, the voltage rises rapidly to the desired value, and due to the formation of a film, the current then drops sharply. Thereafter, the process needs to rely on gradually increasing the voltage to continue. The rate at which the voltage increases is determined by the decrease in current. China’s aviation industry has successfully developed thick-film anodization, which has been put into use.
Titanium alloys possess excellent properties such as good chemical stability, high specific strength, and the ability to maintain their strength even in environments with temperatures ranging from 400 to 500°C; as a result, they have become new types of structural materials widely used in the chemical industry and the aerospace industry. However, the problems associated with titanium alloys in practical applications are that they can cause galvanic corrosion in other materials when in contact with them, and they are prone to scratching and corrosion under moderate to high loads. A way to overcome these practical difficulties is to alter the surface properties of titanium alloys, and anodic treatment has been found to be an effective and simple method for this purpose. There are numerous patent reports on the anodization of titanium alloys, and recommended electrolytes include various solutions such as sulfuric acid, organic acids, nitrates, and caustic alkalis. It can be seen that titanium alloys can easily form a film through anodization in acidic, neutral, and alkaline electrolytes. However, the thickness of the film is generally confined to the range of 0.1–0.2 mm. Within this thickness range, the surface of the film exhibits various colors due to light interference, which is why it is called an interference film. The operating temperature of the solution is 25–55°C; a uniform film cannot be obtained when the temperature is below 25°C ； If the temperature is above the upper limit, the membrane becomes loose and porous with low hardness. To dissipate the heat accumulated during the process, stirring measures can be taken. Anodization uses a half-wave rectified current; when the component is placed in the tank and the current is applied, the voltage rises rapidly to the desired level. Due to the formation of a film, the current then drops sharply. Thereafter, the process must continue by gradually increasing the voltage. The rate at which the voltage is increased is determined by the rate of decline of the current. China’s aviation industry has successfully developed thick-film anodization, which is now in use.
Titanium alloys possess excellent properties such as good chemical stability, high specific strength, and the ability to maintain their strength even in environments with temperatures ranging from 400 to 500°C; as a result, they have become new types of structural materials widely used in the chemical industry and the aerospace industry. However, the problems associated with titanium alloys in practical applications are that they can cause galvanic corrosion in other materials when in contact with them, and they are prone to scratching and corrosion under moderate to high loads. A way to overcome these practical difficulties is to alter the surface properties of titanium alloys, and anodic treatment has been found to be an effective and simple method for this purpose. There are numerous patent reports on the anodization of titanium alloys, and recommended electrolytes include various solutions such as sulfuric acid, organic acids, nitrates, and caustic alkalis. It can be seen that titanium alloys can easily form a film through anodization in acidic, neutral, and alkaline electrolytes. However, the thickness of the film is generally confined to the range of 0.1–0.2 mm. Within this thickness range, the surface of the film exhibits various colors due to light interference, which is why it is called an interference film. The operating temperature of the solution is 25–55°C; a uniform film cannot be obtained when the temperature is below 25°C ； If the temperature is above the upper limit, the membrane becomes loose and porous with low hardness. To dissipate the heat accumulated during the process, stirring measures can be taken. Anodization uses a half-wave rectified current; when the component is placed in the tank and the current is applied, the voltage rises rapidly to the desired level. Due to the formation of a film, the current then drops sharply. Thereafter, the process must continue by gradually increasing the voltage. The rate at which the voltage is increased is determined by the rate of decline of the current. China’s aviation industry has successfully developed thick-film anodization, which is now in use.
Contact with other materials can easily cause galvanic corrosion in those materials, and it is prone to scratching and corrosion under moderate to high load conditions. A way to overcome these practical difficulties is to alter the surface properties of titanium alloys, and anodic treatment has been found to be an effective and simple method for this purpose. The electrolytes for the anodization of titanium alloys include various solutions such as sulfuric acid, organic acids, nitrates, and caustic alkalis. Titanium alloys can easily form a film through anodization in acidic, neutral, and alkaline electrolytes. 1# mopeizhi
Analysis of the standards in China’s non-ferrous metals industry: At present, the standard-setting work in China’s non-ferrous metals industry is in line with the needs of this sector, and a relatively comprehensive set of standards for non-ferrous metals has been established. By the end of 2007, China’s non-ferrous metals industry had a total of **851 national standards and 947 industry standards. In the presence of relevant international standards or advanced foreign standards, China’s non-ferrous metal standards give priority to adopting such standards” ； China’s non-ferrous metal standards, which lack corresponding international or advanced foreign standards, represent domestic independent innovation and are standards with \"Chinese characteristics\". Such a standard system is capable of meeting the needs of China’s import and export trade in non-ferrous metal products, and it is suited to the actual conditions of the development of China’s non-ferrous metals industry. 1. Actively promote the transformation and ensure the smooth progress of standard adoption efforts. “Standard adoption” refers to the situation where “a standard is equivalent to the corresponding international standard, or only minor modifications have been made to the international standard” (the definition is taken from GB/T20000.2-2001, ‘Guidelines for standardization work – Part 2: Rules for adopting international standards’). In terms of the adoption of international standards, China’s non-ferrous metal standards and industry standards have translated 225 out of the 380 existing international standards (ISO). Of these, 23 were adopted identically, 104 were adopted with modifications, and 98 were adopted in a non-equivalent manner (since the international standards adopted in a non-equivalent manner were all versions from before 2001, they are considered to be part of standard adoption). The rate of standard adoption (translation rate) reached 59.2%. Among the 155 international standards that have not been adopted, 19 cannot be adopted due to obsolescence, 8 cannot be adopted immediately as the international standards are under revision, and the remaining 128 will be included in the adoption plan, with adoption expected to be completed by 2010. Therefore, by 2010, the adoption rate of international standards in our country will exceed 95%. In addition, among China’s non-ferrous metal standards, 79 **national standards** and 46 industry standards \"refer\" to advanced foreign standards such as ASTM, ANSI, EN, and JIS, with a degree of consistency equivalent to \"modified adoption\". The standard adoption level for non-ferrous metals in our country is higher than that of advanced foreign standardization organizations such as the EU, the United States, and Japan. Currently, of the 270 EU standards (EN) related to non-ferrous metals in total, 32 are based on ISO standards. In the development of EU standards, reference to ISO standards is not common; the adoption rate is only 8.4% ； EU standards have only been developed on a large scale in recent years. Their approach is to create the conditions necessary to convert EN standards into ISO standards once those standards are issued; they are quite proactive in transforming regional standards into international standards ； Among the 588 ASTM and ANSI standards, no indication is given regarding whether ISO standards are adopted; therefore, it is not possible to determine the extent to which these standards follow ISO standards. However, as far as we know, U.S. standards for non-ferrous metals generally do not adopt international standards. Only Japan has such standards; it is quite proactive in adopting ISO standards, with a high adoption rate. Among the 409 JIS standards, 125 have been adopted in an equivalent or modified form based on international standards, resulting in an adoption rate of 32.9%, which is comparable to the level in China, where 127 international standards have been adopted in an equivalent or modified form. There are also 98 standards that have been adopted in a non-equivalent manner in our country. It can be seen that the situation regarding the adoption of international standards in our country is quite good, and it is suitable for the development of our country’s non-ferrous metals industry. 2. Independent innovation and the development of standards with Chinese characteristics: Among China’s many non-ferrous metal products, there are certain varieties that are unique to China. At present, there are no corresponding international standard technical committees for these varieties, nor any international standards; the number of relevant other standards is also very limited. China’s non-ferrous metal products, such as aluminum hydroxide, aluminum powder, magnesium powder, gallium, aluminum fluoride, cryolite, titanium alloys, thallium, zirconium, tungsten, molybdenum, antimony, vanadium, etc., are all considered “Made in China”; no corresponding standards can be found in foreign standardization systems ； At the same time, China has a large production volume of lead and lead alloys, but there is no international technical committee for standardization of lead and lead alloys within the International Organization for Standardization (ISO), nor are there any international standards in this area. Moreover, advanced foreign standards also lack any standards related to lead. China-specific standards of this kind account for 826 in China’s non-ferrous metals standardization system** – 302 of these are national standards and 524 are industry standards – representing 45.9% of the total number of standards. 3. Bulk trading to meet international market demands: At present, the overall number of standards and their quality level for non-ferrous metals in China are sufficient to meet the development needs of this industry. The technical standards for major non-ferrous metal products, such as aluminum ingots for remelting, aluminum alloy ingots, aluminum alloy building profiles, aluminum foil, cathode copper, copper pipes for air conditioning, lead ingots, zinc ingots, tin ingots, magnesium, gold ingots, and silver ingots, as well as the corresponding standards for chemical analysis of these non-ferrous metals, are in line with international standards and have reached an advanced international level ； The quality of these products is on par with international standards; 56 brands of 8 types of products, including copper, aluminum, lead, zinc, tin, nickel, aluminum alloys, and silver, are registered at the LME (London Metal Exchange) and the London Bullion Market Association. For subsequent non-ferrous metal processed products, the quality of copper and aluminum processed materials has further improved. In particular, some key products that are produced in large quantities and used widely, such as copper and copper alloy pipes for air conditioning, aluminum alloy profiles for construction and industrial use, as well as certain aluminum and copper sheets, strips, and foils, have reached the standards of developed countries. These products not only meet the needs of domestic industries but are also exported in large quantities to countries such as Japan, Europe, and the United States. Nevertheless, some copper and aluminum processed products still fall short when compared to developed countries such as the United States, mainly due to unstable performance; there is still a need to import certain high-precision products. Last year, at the National Quality Work Conference, Premier Wen spoke highly of this, saying: “The technical standards and actual quality of non-ferrous metals have been brought in line with international levels.” ”This is an affirmation and encouragement for the quality standard work in the non-ferrous metals industry. III. The status of international standardization for non-ferrous metals in China China is a major country in the production of non-ferrous metals. These standards cover various non-ferrous metals such as copper, aluminum, lead, zinc, magnesium, titanium, tin, nickel, and lithium; the specific items are listed in Table 2. “Projects planned to be completed during the 11th Five-Year Plan period for formulating English versions of standards for non-ferrous metals: Serial number, Standard number, Standard name. 1. GB/T8013.1 Aluminum and aluminum alloy anodized films and organic polymer films – Part 1: Anodized films; 2. GB/T8013.2 Aluminum and aluminum alloy anodized films and organic polymer films – Part 2: Anodized composite films; 3. GB/T8013.3 Aluminum and aluminum alloy anodized films and organic polymers – Part 3: Organic polymer spray-coated films; 4. GB5237.1 Aluminum alloy building profiles – Part 1: Base materials; 5. GB5237.2 Aluminum alloy building profiles – Part 2: Anodized and colored profiles; 6. GB5237.3 Aluminum alloy building profiles – Part 3: Electrophoretically painted profiles; 7. GB5237.4 Aluminum alloy building profiles – Part 4: Powder-coated profiles; 8. GB5237.5 Aluminum alloy building profiles – Part 5: Fluorocarbon paint-coated profiles; 9. GB/T5237.6 Aluminum alloy building profiles – Part 6: Insulated profiles; 10. GB/T20251 Nickel foam for batteries; 11. GB20424 Limits on harmful elements in heavy metal concentrate products; 12. GB/T20928 Internal threaded copper pipes; 13. GB/T467 Cathode copper; 14. GB/T469 Lead ingots; 15. GB/T470 Zinc ingots; 16. GB/T3880.1 Rolled sheets and strips of aluminum and aluminum alloys for general industrial use – Part 1: General requirements; 17. GB/T3880.2 Rolled sheets and strips of aluminum and aluminum alloys for general industrial use – Part 2: Mechanical properties; 18. GB/T3880.3 Rolled sheets and strips of aluminum and aluminum alloys for general industrial use – Part 3: Dimensional tolerances; 19. GB20664 Limits on natural radioactivity in non-ferrous metal mineral products; 20. GB/T3499 Primary magnesium ingots; 21. GB/T728 Tin ingots; 22. GB/T6516 Electrolytic nickel
Why anodize: The problems with titanium alloys in applications are that they can cause galvanic corrosion in other materials when in contact with them, and they are prone to scratching and corrosion under moderate to high loads. A way to overcome these practical difficulties is to alter the surface properties of titanium alloys, and anodic treatment has been found to be an effective and simple method for this purpose. The method: There are numerous patent reports on the anodization of titanium alloys, and the recommended electrolytes include various solutions such as sulfuric acid, organic acids, nitrates, and caustic alkalis. It can be seen that titanium alloys can easily form a film through anodization in acidic, neutral, and alkaline electrolytes. However, the thickness of the film is generally confined to the range of 0.1–0.2 mm. Within this thickness range, the surface of the film exhibits various colors due to light interference, which is why it is called an interference film. The operating temperature of the solution is 25–55°C; a uniform film cannot be obtained when the temperature is below 25°C ； If the temperature is above the upper limit, the membrane becomes loose and porous with low hardness. To dissipate the heat accumulated during the process, stirring measures can be taken. Anodization uses a half-wave rectified current; when the component is placed in the tank and the current is applied, the voltage rises rapidly to the desired level. Due to the formation of a film, the current then drops sharply. Thereafter, the process must continue by gradually increasing the voltage. The rate at which the voltage is increased is determined by the rate of decline of the current. China’s aviation industry has successfully developed thick-film anodization, which is now in use.
To effectively improve the resistance of titanium alloy anodized films to coulombic corrosion, a coulombic-corrosion-resistant titanium alloy anodized film was prepared using pulse anodization technology in solutions of 300–400 g/L H2SO4 and 50–120 g/L H3PO4, at a current density of 2–3 A/dm2 and a temperature of 0–10°C
Titanium alloys possess excellent properties such as good chemical stability, high specific strength, and the ability to maintain their strength even in environments with temperatures ranging from 400 to 500°C; as a result, they have become new types of structural materials widely used in the chemical industry and the aerospace industry. However, the problems associated with titanium alloys in practical applications are that they can cause galvanic corrosion in other materials when in contact with them, and they are prone to scratching and corrosion under moderate to high loads. A way to overcome these practical difficulties is to alter the surface properties of titanium alloys, and anodic treatment has been found to be an effective and simple method for this purpose. There are numerous patent reports on the anodization of titanium alloys, and recommended electrolytes include various solutions such as sulfuric acid, organic acids, nitrates, and caustic alkalis. It can be seen that titanium alloys can easily form a film through anodization in acidic, neutral, and alkaline electrolytes. However, the thickness of the film is generally confined to the range of 0.1–0.2 mm. Within this thickness range, the surface of the film exhibits various colors due to light interference, which is why it is called an interference film. The operating temperature of the solution is 25–55°C; a uniform film cannot be obtained when the temperature is below 25°C ； If the temperature is above the upper limit, the membrane becomes loose and porous with low hardness. To dissipate the heat accumulated during the process, stirring measures can be taken. Anodization uses a half-wave rectified current; when the workpiece is placed in the tank and the current is applied, the voltage rises rapidly to the desired level. Due to the formation of a film, the current then drops sharply. Thereafter, the process must continue by gradually increasing the voltage. The rate at which the voltage is increased is determined by the rate of decline in the current. China’s aviation industry has successfully developed thick-film anodization technology, which is now in use. 1# mopeizhi