There are significant differences between Inconel 600 and Inconel 718 in many aspects, including chemical composition, corrosion resistance, high temperature performance, mechanical properties and application areas. The following is a detailed comparison:
1. Chemical composition
Inconel 600: The main components are nickel (about 72%), chromium (14-17%), iron (6-10%) and copper (0.5%), and also contain small amounts of molybdenum, manganese, silicon and carbon. The high nickel content of this alloy makes it have good high temperature corrosion resistance.
Inconel 718: The nickel content in the alloy is about 52-55%, and it also contains high chromium (19-22%), niobium (4.75-5.5%), titanium (3-5%) and aluminum (0.65-1.15%). The addition of these elements makes the 718 alloy have better performance in high temperature and corrosive environments.
2. Corrosion resistance
Nickel-based alloy 600: It has good resistance to various corrosive media, including acids, alkalis and oxidants. It is particularly suitable for environments containing chloride ions, as well as high concentrations of chloride and caustic solutions containing OH.
Nickel-based alloy 718: It also has excellent corrosion resistance and can perform well in corrosive media such as acids, alkalis, and chlorides. In addition, 718 alloy also shows good resistance to pitting, crevice corrosion and stress corrosion in neutral chloride ion media.
3. High temperature performance
Nickel-based alloy 600: It can maintain good stability and corrosion resistance in high temperature environments, but its maximum operating temperature generally does not exceed 1100.
Nickel-based alloy 718: It has excellent high temperature strength and can maintain high strength and stiffness even at high temperatures. Its maximum high temperature resistance temperature can reach about 704C, which makes it more widely applicable in high temperature application environments.
4. Mechanical properties
Nickel-based alloy 600: It has good mechanical properties, including high strength and hardness, as well as good machinability. However, its mechanical strength may be limited in extremely high temperature and corrosive environments.
Nickel-based alloy 718: After heat treatment and cold drawing hardening, the 718 alloy has high strength and certain flexibility and plasticity. At the same time, it also has excellent fatigue life and good welding performance.
5. Application fields
Nickel-based alloy 600: Widely used in chemical, petroleum and nuclear industries, especially suitable for manufacturing equipment and components in high temperature and corrosive environments, such as heaters, heat exchangers, reactors and pipelines. In addition, it is also commonly used in the manufacture of fuel elements and structural materials for nuclear reactors.
Nickel-based alloy 718: Due to its excellent high temperature strength, corrosion resistance and toughness, it is widely used in high temperature, high pressure and corrosive environments in aerospace, shipbuilding, petrochemical and other fields, such as turbine blades, gas turbines, aircraft engines, oil drill bits, etc.
