What is the difference between 9Cr18 and 440C stainless steel materials?

9Cr18 and 440C are both types of martensitic stainless steel, which means they are both hardened by heat treatment and are known for their high strength and corrosion resistance.

9Cr18 and 440C belong to the category of martensitic stainless steels, renowned for their exceptional hardness and wear resistance post-quenching, making them suitable for high-wear applications. Both materials can achieve hardness levels of HRC60° and above following heat treatment.9Cr18 is characterized by its high carbon and chromium content, rendering it ideal for producing components subjected to high wear, heavy loads, and non-corrosive environments, such as automatic control valve parts. However, it is susceptible to oxidation upon exposure to water or water vapor, necessitating its use in environments where contact with moisture is minimized.


Differences in chemical composition

Grade C Cr Mn Si P S Ni Mo
9Cr18 0.95-1.2 17.0-19.0 1.0 1.0 0.035 0.030 0.60 0.75
440C 0.95-1.2 16.0-18.0 1.0 1.0 0.040 0.030 0.60 0.75

In summary, 440C stainless steel typically offers higher hardness and slightly better corrosion resistance compared to 9Cr18, but both materials are suitable for a range of applications where high performance and durability are essential.

Post time: Apr-02-2024