Mechanical Properties of Austenitic Stainless Steel S 31668 0Cr18Ni12Mo2Ti
This paper aims to provide an overview of the mechanical properties of austenitic stainless steel S 31668 0Cr18Ni12Mo2Ti and to discuss the effects of various factors, such as alloy composition, heat treatment, fabrication and service environment, on those properties.
Austenitic stainless steels, such as S 31668 0Cr18Ni12Mo2Ti, are among the most commonly used materials for manufacturing parts and components in many industries. This family of alloys is renowned for its excellent corrosion and oxidation resistance and high ductility and toughness. S 31668 0Cr18Ni12Mo2Ti is a highly popular grade for its combination of good strength and corrosion resistance. The key elements of this alloy are Cr, Ni, Mo and Ti. The mechanical properties of S 31668 0Cr18Ni12Mo2Ti are further discussed below.
The mechanical properties of S 31668 0Cr18Ni12Mo2Ti depend on the alloys chemical composition and microstructure. For example, higher levels of chromium, nickel, molybdenum and titanium can result in increased strength, toughness and corrosion resistance. Heat treatment, fabrication and service environment also play a role in determining the mechanical properties of alloys. Quenching and tempering applications are known to improve the hardness, ductility and yield strength of the alloy.
Hardness is an important indicator of the wear resistance and fatigue strength of S 31668 0Cr18Ni12Mo2Ti. Depending on the quenching temperature and other process parameters, the hardness of S 31668 0Cr18Ni12Mo2Ti can range from 26 HRC to 52 HRC.
The ultimate tensile strength (UTS) of S 31668 0Cr18Ni12Mo2Ti is in the range of 600 MPa to 1200 MPa. The yield strength of S 31668 0Cr18Ni12Mo2Ti lies in the range of 300 MPa to 800 MPa. The 0.2% and 0.5% offset yield strength for the alloy are in the range of 220 MPa to 500 MPa.
Ductility is an important property of S 31668 0Cr18Ni12Mo2Ti. Good formability of the alloy is usually achieved with a 0.2% elongation of over 40%.
The impact toughness of S 31668 0Cr18Ni12Mo2Ti is usually in the range of 15 Joules to 45 Joules. Higher impact toughness is usually associated with lower hardness. In general, the impact toughness decreases with increasing hardness.
The elastic modulus of S 31668 0Cr18Ni12Mo2Ti is 200 GPa. This is classified as a ‘high elastic modulus’ material.
The thermal conductivity of S 31668 0Cr18Ni12Mo2Ti is in the range of 15 W/mK to 30 W/mK. The thermal expansion coefficient of the alloy is 8.1 x 10-6/K.
As discussed above, the mechanical properties of S 31668 0Cr18Ni12Mo2Ti are strongly affected by the alloys chemical composition, microstructure and service environment. The mechanical properties of the alloy make it an ideal material for a variety of applications, such as valves, pumps, elbows and flanges in fluid handling systems, columns and reactors in chemical plants and pipelines in the offshore and marine sectors.
