Chemical composition of 00Cr11Ni22Si6Mo2Cu (SS-920) steel

参考文献

AISI Type SS-920 stainless steel is a chromium-nickel-molybdenum-copper alloy intended primarily for use at elevated temperatures, such as in heat exchangers, boilers and aerospace applications. This alloy is still relatively new in the stainless steel market and there is limited information available on its composition, physical and mechanical properties and application.

Chemical composition of SS-920 according to American Iron and Steel Institute (AISI) includes:

• Carbon (C) - 0.02%

• Silicon (Si) - 11.20%

• Chromium (Cr) - 20.00%

• Nickel (Ni) - 21.50%

• Molybdenum (Mo) - 2.00%

• Del Or (Cu) - 0.50%

• Manganese (Mn) - 1.00%

• Phosphorus (P) - 0.040%

• Sulfur (S) - 0.030%

• Tin (Sn) - 0.00%

• Iron (Fe) - Bal.

Corrosion resistance of SS-920 is provided by the Chromium (Cr) content which is present at a minimum of 20.00%. Nickel (Ni) content further improves corrosion resistance and gives additional strength to the alloy. The Molybdenum (Mo) and Copper (Cu) content helps to provide mechanical strength and improve the high-temperature properties of the alloy, thus providing good oxidation resistance. Additionally, SS-920 exhibits high tensile and creep strength which makes it suitable for service temperatures up to 750°F (400°C).

The addition of relatively high Silicon (Si) content further improves the high- temperature, oxidation and non-scaling properties of the alloy.

Though SS-920 has good creep strength and oxidation resistance at elevated temperatures, it is not suitable for service in sulfur-containing environments such as hydrochloric acid and alkaline solutions. Thus, the alloy is best suited for application in neutral pH aqueous solutions and those that contain chlorides.

Applications for AISI Type SS-920 include components for aircraft and aviation engines and gas turbines, heat exchangers and cladding for textile and paper industries. The alloy is also used in medical and nuclear industry thanks to its high corrosion-resistance and mechanical strength.

AISI Type SS-920 stainless steel is not maintained in the inventory of many steel suppliers and it is difficult to obtain the alloy quickly. Thus, precautions should be taken in the selection of the alloy and to assure that the intended application and processing conditions are compatible with providing the desired characteristics.

References

1. American Iron and Steel Institute (AISI), AISI Type SS-920, Accessed on: 30 April 2018.

2. Bhansali, M. (2017), Stainless Steel SS 920 - Composition, Properties and Applications, Accessed on: 30 April 2018.

3. Steel Distribution Services (2018), SS-920, Accessed on: 30 April 2018.

4. The Atlas Steels (2018), AISI Type 920 (SS-920), Accessed on: 30 April 2018.

Stainless steel SS-920 is a corrosion and heat resistant type of stainless steel with the following typical chemical composition:

Carbon (C) : 0.04 - 0.08%

Manganese (Mn) : 1.00 - 2.00%

Silicon (Si) : Max. 1.00%

Phosphorus (P) : Max. 0.030%

Sulfur (S) : Max. 0.030%

Cr : 11.0 - 12.0%

Ni : 21.0 - 23.0%

Mo : 2.00 - 2.50%

Cu : 2.00 - 2.50%

SS-920 can resist corrosion, high heat and heat treatment, is highly resistant to stress corrosion and cracking, has superior cold forming and drawing properties, and a low coefficient of thermal expansion. It also has Machinability ratings of 46-56 compared to Carbon Steels of 41-50. Because of its properties, SS-920 is commonly employed for general applications in oil refineries, petrochemical plants, power plants and onshore and offshore oil and gas platforms. SS-920 can be used in a number of applications such as pumps, valves, heat exchangers, pipes, bolts and flanges.

SS-920 has superior corrosion and high heat resistance compared to other stainless steels, which makes it an ideal material in many different industries. Its superior resistance to stress corrosion and cracking makes it great for applications with exposure to extremely harsh environments. Its machinability ratings make it easier to machine, which can reduce product expenses while allowing for high tolerance levels. Its low coefficient of thermal expansion makes it less susceptible to thermal shock, which allows it to handle thermal loads better than other stainless steels. Furthermore, SS-920 has superior forming and drawing properties, which are beneficial for making complex shapes.

Overall, stainless steel SS-920 is an ideal material for applications in harsh environments and its superior properties make it well-suited for complex shapes.