Introduction
S34771Austenitic stainless steel offersstrength and stability to many applications. It is a grade of stainless steel composed of 1Cr19Ni11Nb withelemental composition that provides a combination of corrosion and heat resistance, propertiesthat make it ideally suited for a wide range of structural applications.
Chemical Composition
Austenitic stainless steel S34771 consists of 1Cr19Ni11Nb. Its chemical composition, as shown below, provides an excellent balance of corrosion resistance, physical properties and performance.
Component Mass (%)
Carbon (C) 0.045
Manganese (Mn) 1.00
Sulfur (S) 0.030
Phosphorus (P) 0.035
Nitrogen (N) 0.070
Silicon (Si) 0.60
Chromium (Cr) 18.00-19.00
Nickel (Ni) 10.00-12.00
Titanium (Ti) 0.07-0.12
Niobium (Nb) 0.10-0.14
Iron (Fe) Balance
Mechanical Properties
Austenitic stainless steel S34771 has several important mechanical properties.
Yield Strength (MPa)
Annealed 310-410
Ultimate Tensile Strength (MPa)
Annealed 450-590
Elongation (% in 50 mm)
Annealed 40+
Hardness
Annealed Brinell 119-187
Stress Relieving
Stress-relieving heat treatment of austenitic stainless steel S34771 is not normally necessary, as it is resistant to stress corrosion.
Welding
Austenitic stainless steel S34771 can be welded using any of the standard welding processes; however, the welding should be done only after the parts have reached room temperature. If the parts are to be post-welded heat treated, the welding should be done prior to the heat treatment. When welding austenitic stainless steel, it is advised to use a filler metal of similar composition in order to maintain the stainless properties of the joined parts.
Heat Treatment
Austenitic stainless steel S34771 can be heat treated in order to alter its mechanical and physical properties. Annealing is a process used to improve cold workability and to bring out the grain structure of the material. This process is typically performed before welding and should be done in a controlled atmosphere or vacuum. The annealing temperature of austenitic stainless steel S34771 is typically between 1050°C to 1150°C (1920°F to 2100°F).
Intermetallic Hardeners
Austenitic stainless steels contain amounts of intermetallic hardeners, such as titanium and niobium, which help increase their strength, hardness and corrosion resistance. At higher temperatures, these hardeners combine with chromium and other elements, such as carbon and manganese, to form intermetallics, which can provide further strength, hardenability and improved corrosion resistance.
Applications
Austenitic stainless steel S34771 is a versatile grade of stainless steel that can be used in a wide range of applications. Its strength and stability make it ideal for structures and components that must endure harsh chemical or environmental conditions. It can be used for some chemical containers,pressure vessels and valves, chemical storage tank, and pipe systems that transport corrosive material. Other applications include hot water heaters,automotive components, power generating plants, and food processing equipment.
Conclusion
Austenitic stainless steel S34771 offers excellent mechanical and physical properties, with a high level of corrosion resistance. Its balance of properties makes it suitable for a wide range of applications in both the chemical and construction industries. Its versatility makes it an ideal material for many industrial applications.
