Technological properties of 00Cr11Ni22Si6Mo2Cu (SS-920) steel

Introduction

SS-920 is a stainless steel from China with the chemical composition of 0.04%-0.09%C, 0.10%-0.22%Si, 0.90%-1.30%Mn, 3.00%-4.00%Ni, 11.00%-22.00%Cr, 2.00%-6.00%Mo and ≤2.00%Cu. This type of steel has good corrosion resistance, high hardness and good wear resistance. It is used in applications such as knives, cutters, tools and wear-resistant parts.

Manufacturing process

The SS-920 stainless steel is produced through an electric arc furnace, an induction furnace or a vacuum furnace. The furnace is heated to temperatures above 1700℃, followed by a rapid cooling process. The hot rolled SS-920 sheets that come out of the furnace are then cold rolled. The cold rolling process makes the steel sheets thinner and stronger. Finally, the cold rolled sheets are heat treated, to get the desired characteristics like strength and hardness.

Physical Properties

The SS-920 stainless steel has a density of 8.6 g/cm3 and a modulus of elasticity of 207 GPa, which gives it high strength and elasticity. The melting point of the steel is 1450-1460℃ and its electrical resistivity is 41.4 microhm·cm. Its thermal conductivity is 16.2W/(m·K) and its coefficient of thermal expansion is 13.0 µm/(m·K). These physical characteristics make SS-920 a good choice for heavy vehicles and machinery components.

Mechanical Properties

The SS-920 stainless steel has a yield strength of Ise = 590 MPa, a tensile strength of Ist = 720 MPa, a percent elongation of >20%, and a Brinell hardness of ≈570 HBW. These mechanical properties make it suitable for use in parts exposed to high loads and shock.

Structural Properties

The SS-920 stainless steel has a ferritic, martensitic, ferritic-martensitic and austenitic-ferritic structure. Its microstructure consists of a layer of austenite, a layer of ferrite, and a thin layer of bainite. These layers are formed by the rapid cooling of the steel after it is heated, which gives it good strength and wear resistance.

Corrosion Resistance

The SS-920 stainless steel has good corrosion resistance against weak organic acids, salts, and some atmospheric conditions. Its resistance to oxidation and corrosion is 2-3 times higher than standard carbon steel. This makes it suitable for use in environments exposed to corrosive materials or salt spray.

Conclusion

SS-920 is a stainless steel from China with a chemical composition of 0.04%-0.09%C, 0.10%-0.22%Si, 0.90%-1.30%Mn, 3.00%-4.00%Ni, 11.00%-22.00%Cr, 2.00%-6.00%Mo and ≤2.00%Cu. It has good corrosion resistance, high strength and good wear resistance. It is manufactured in furnaces and has physical and mechanical properties that make it suitable for use in heavy machinery and vehicles. Additionally, its corrosion resistance is 2-3 times higher than that of standard carbon steel, making it suitable for use in corrosive environments.

SS-920 is a super-austenitic stainless steel with excellent resistance to pitting and crevice corrosion and good stress corrosion cracking resistance. It has relatively good mechanical properties in the fully annealed condition and is used for new construction and renovation of various process equipments and structural facilities in the chemical and power industries.

The chemical composition of SS-920 steel is as follows: C ≤ 0.03, Mn ≤ 2.00, Cr 11.00~14.00, Ni 21.00~25.00, Si ≤ 1.00, Mo ≤ 2.50, Cu ≤ 0.75, P ≤ 0.040, S ≤ 0.030. Its hardness is between HRC22-25.

SS-920 stainless steel has a very good resistance to general and intergranular corrosion in an oxidizing acid environment. The addition of molybdenum, copper and niobium greatly improves the resistance to boiling nitrate sulfuric acid. This steel is particularly suitable for various applications in chemical process equipments.

SS-920 has good processability and weldability. The toughness of its welding joint can reach RT ≥ 20°C. Its post-weld heat treatment can eliminate the internal stress caused by welding, thereby ensuring the performance stability of the welding joint.

The high temperature resistance of SS-920 is superior to general stainless steel. Its service temperature can reach up to 550 ℃. It is often used in chemical and power industries to manufacture high-temperature equipment. However, SS-920 is not suitable for use in an environment with a chlorination atmosphere at a temperature between 0-450 ℃ or in a reducing atmosphere exceeding 450 ℃.

In summary, SS-920 is a super-austenitic stainless steel with excellent corrosion resistance and heat resistance. It has good processability and weldability, which makes it suitable for making various process equipment and structural components in the chemical and power industries.