Corrosion resistant alloys
Metal corrosion-resistant materials, relative to non-metallic corrosion-resistant materials, metal corrosion-resistant materials are mainly iron-based alloys (corrosion-resistant stainless steel); nickel-based alloys (Ni-Cr alloy, Ni-Cr-Mo alloy, Ni-Cu alloy, etc.); reactive metals.
Classification
Corrosion-resistant stainless steel
The most common corrosion-resistant alloys Hastelloy
Most common corrosion-resistant alloys Hastelloy
Mainly common corrosion-resistant 300 series stainless steels 304, 316L, 317L, etc. that are resistant to corrosion such as atmosphere or seawater; stronger corrosion-resistant austenitic stainless steels 904L, 254SMO; duplex steels 2205, 2507, etc.; Cu-containing corrosion-resistant alloy 20 alloys, etc.
Nickel-based corrosion-resistant alloys
Mainly Hastelloy and Ni-Cu alloy, etc., because the metal Ni itself is face-centered cubic structure, crystallographic stability makes it able to accommodate more alloying elements than Fe, such as Cr, Mo, Al, etc., so as to achieve the ability to resist various environments; at the same time, nickel itself has a certain corrosion resistance, especially the resistance to stress corrosion caused by chloride ions. In strong reductive corrosive environments, complex mixed acid environments, solutions containing halogen ions, nickel-based corrosion resistant alloys represented by Hastelloy have an absolute advantage over iron-based stainless steels.
Nickel-based alloys not only have unique resistance to corrosion and even high temperature corrosion in many industrial corrosive environments, but also have high strength, good plastic toughness, smelting, casting, hot and cold deformation, processing and forming and welding properties, and are widely used in petrochemical, energy, marine, aerospace and other fields [1] .
Reactive metals
Also have good corrosion resistance, typical representatives are Ti; Zr; Ta, etc.; the most typical representative is Ti; titanium has a wide range of applications, mainly used in some stainless steel can not adapt to the corrosive environment. Titanium corrosion resistance principle: in the oxidizing atmosphere, the formation of dense oxide film to provide protection; so generally can not be used in a more reductive or sealing that high corrosive environment (oxygen-deficient environment), with the same time, the application temperature of titanium is generally less than 300 degrees Celsius. Special attention should be paid to the active metal can not be used in the environment containing fluorine. (Such as hydrofluoric acid environment can be used Hastelloy C2000, NiCu alloy, etc.).
Chinese grades of corrosion resistant alloys include: NS111,NS112,NS113,NS131,NS141,NS142,
NS143,NS311,NS314,NS315,NS321,NS322,NS331,NS332,
NS333, NS334, NS335, NS336, NS334, NS341, NS411, etc.
Other national grades of corrosion resistant alloys include: incoloy800/800H; incoloy825; inconel600/690/625; hastelloyB/B2/C/C-4, etc.
Classification
Corrosion-resistant stainless steel
The most common corrosion-resistant alloys Hastelloy
Most common corrosion-resistant alloys Hastelloy
Mainly common corrosion-resistant 300 series stainless steels 304, 316L, 317L, etc. that are resistant to corrosion such as atmosphere or seawater; stronger corrosion-resistant austenitic stainless steels 904L, 254SMO; duplex steels 2205, 2507, etc.; Cu-containing corrosion-resistant alloy 20 alloys, etc.
Nickel-based corrosion-resistant alloys
Mainly Hastelloy and Ni-Cu alloy, etc., because the metal Ni itself is face-centered cubic structure, crystallographic stability makes it able to accommodate more alloying elements than Fe, such as Cr, Mo, Al, etc., so as to achieve the ability to resist various environments; at the same time, nickel itself has a certain corrosion resistance, especially the resistance to stress corrosion caused by chloride ions. In strong reductive corrosive environments, complex mixed acid environments, solutions containing halogen ions, nickel-based corrosion resistant alloys represented by Hastelloy have an absolute advantage over iron-based stainless steels.
Nickel-based alloys not only have unique resistance to corrosion and even high temperature corrosion in many industrial corrosive environments, but also have high strength, good plastic toughness, smelting, casting, hot and cold deformation, processing and forming and welding properties, and are widely used in petrochemical, energy, marine, aerospace and other fields [1] .
Reactive metals
Also have good corrosion resistance, typical representatives are Ti; Zr; Ta, etc.; the most typical representative is Ti; titanium has a wide range of applications, mainly used in some stainless steel can not adapt to the corrosive environment. Titanium corrosion resistance principle: in the oxidizing atmosphere, the formation of dense oxide film to provide protection; so generally can not be used in a more reductive or sealing that high corrosive environment (oxygen-deficient environment), with the same time, the application temperature of titanium is generally less than 300 degrees Celsius. Special attention should be paid to the active metal can not be used in the environment containing fluorine. (Such as hydrofluoric acid environment can be used Hastelloy C2000, NiCu alloy, etc.).
Chinese grades of corrosion resistant alloys include: NS111,NS112,NS113,NS131,NS141,NS142,
NS143,NS311,NS314,NS315,NS321,NS322,NS331,NS332,
NS333, NS334, NS335, NS336, NS334, NS341, NS411, etc.
Other national grades of corrosion resistant alloys include: incoloy800/800H; incoloy825; inconel600/690/625; hastelloyB/B2/C/C-4, etc.
Deformed high temperature alloys
Powder Metallurgy High Temperature Alloys
Iron-based cast high-temperature alloys
Nickel-based cast high-temperature alloys
Cobalt-based cast high-temperature alloys
Directional eutectic casting of high temperature alloys
Single crystal casting high temperature alloys
Casting high temperature alloys
Corrosion resistant high temperature alloys