Hastelloy is an important high-performance alloy material with excellent corrosion resistance, and is widely used in chemical industry, aviation, aerospace, marine and other fields. Different corrosion environments have different effects on the corrosion behavior of Hastelloy alloys. Therefore, when selecting suitable Hastelloy alloy materials, it is necessary to consider factors such as the type of corrosive medium, temperature, pressure, flow rate, and the corrosion resistance of the alloy itself. Factors such as physical properties and processing properties. The following are some common methods and experiences for selecting appropriate Hastelloy materials to cope with different corrosive environments.
1. Acidic medium
In acidic media, the corrosion resistance of Hastelloy depends on alloy composition, temperature, concentration, flow rate and other factors. Generally speaking, Hastelloy rich in elements such as molybdenum, tungsten, and chromium has good acid corrosion resistance, especially in high-temperature, high-concentration acidic media, such as sulfuric acid, nitric acid, and hydrofluoric acid. For example, Hastelloy C-276 alloy (UNS N10276) is a Hastelloy alloy rich in molybdenum, chromium, and tungsten. Excellent corrosion resistance, and also has good corrosion resistance in acidic atmosphere.
In addition, different surface treatment methods can be used to improve the corrosion resistance of Hastelloy according to different use environments. For example, through electrochemical polishing, chemical polishing, sandblasting, passivation and other methods, the surface oxide layer, dirt and rust products can be removed, thereby improving the corrosion resistance of Hastelloy.
2. Alkaline medium
In alkaline media, the corrosion resistance of Hastelloy is also an important consideration. Generally speaking, Hastelloy rich in molybdenum, nickel, chromium and other elements has good alkali corrosion resistance, especially in high-concentration, high-temperature, high-pressure alkaline media, such as sodium hydroxide, potassium hydroxide, hydrogen Alumina etc. For example, Hastelloy C-22 alloy (UNS N06022) is a Hastelloy rich in nickel, chromium, and molybdenum, which has excellent corrosion resistance in high-concentration, high-temperature alkaline media.
3. Chloride medium
In media containing chloride, the corrosion resistance of Hastelloy is also an important consideration. Hastelloy rich in molybdenum, chromium, tungsten and other elements has good chlorine corrosion resistance, especially in high-concentration, high-temperature, high-pressure chloride media, such as hydrochloric acid, ferrous chloride, zinc chloride, etc. For example, Hastelloy C-276 alloy (UNS N10276) has excellent corrosion resistance in high-concentration, high-temperature chloride media.
4. Oxidizing media
In oxidizing media, the corrosion resistance of Hastelloy is also an important consideration. For example, in high-temperature, high-pressure water vapor, the corrosion resistance of Hastelloy is very important. Hastelloy alloys rich in chromium, aluminum, tungsten and other elements have good oxidation resistance. For example, C-263 alloy (UNS N07263) is a Hastelloy rich in chromium, aluminum, tungsten. Excellent corrosion resistance in water vapor.
5. Mixed media
In mixed media, the corrosion resistance of Hastelloy depends on the composition of the medium, temperature, pressure, flow rate and other factors. Under normal circumstances, the corrosion resistance of Hastelloy is not uniform, and the appropriate Hastelloy material needs to be selected according to the specific use environment. For example, in the mixed medium containing chloride and sulfuric acid, the C-276 alloy has excellent corrosion resistance; in the mixed medium containing fluoride ions and sulfuric acid, the C-22 alloy has excellent corrosion resistance.
In addition to the above methods, it is also possible to improve its corrosion resistance by changing the composition of the Hastelloy alloy, using different processing techniques and heat treatment techniques. For example, adding elements such as niobium and tantalum to Hastelloy can improve its corrosion resistance; adopting processes such as cold deformation and hot working can improve the mechanical properties and corrosion resistance of Hastelloy; adopting heat treatment processes, such as solution annealing, Aging treatment, etc., can improve the grain boundary stability and corrosion resistance of Hastelloy.
To sum up, choosing the appropriate Hastelloy material to cope with different corrosive environments is a comprehensive issue that requires consideration of multiple factors.
Tianjin Anton Metal Manufacture Co., Ltd. is a company specializing in the production of various nickel-based alloys, Hastelloy alloys and high-temperature alloy materials. The company was established in 2001 with a registered capital of 16.8 million, specializing in the production and sales of alloy materials. Anton Metal’s products are widely used in aerospace, chemical industry, electric power, automobile, nuclear energy and other fields, and can also provide customized alloy material solutions according to customer needs. If you need to know the price consultation of alloy materials or provide customized alloy material solutions, please feel free to contact the sales staff.
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Post time: Sep-02-2023
