Stainless steel is an alloy steel containing at least 10.5% chromium. Stainless steel is broadly categorized into four types based on its crystalline structure: Austenitic, Martensitic, Ferritic, and Duplex Stainless Steel. 440c and 316 are two of the most popular stainless steel grade manufacturers worldwide. Both grades come with unique features and different uses. However, many users still need clarification about which one to choose for their application. In this blog post, we will discuss everything about 440c stainless steel and 316 stainless steel and help you understand their differences.
Difference Between 440c Stainless Steel and 316
Chemical Composition:
440c is a martensitic stainless steel with high carbon content (1.2-1.4%). Its composition contains a high proportion of chromium (16-18%) and added quantities of elements such as molybdenum, manganese, and vanadium. On the other hand, 316 is an austenitic stainless steel containing a low amount of carbon (0.08%) and an increased concentration of chromium and nickel. 316 has added amounts of molybdenum and silicon when compared to 440c.
Corrosion Resistance:
Both 440c and 316 have excellent corrosion resistance properties but differ in the types of corrosion they resist. 316 is suitable for use in harsh environments such as marine applications, chemical processing, or industrial exposure to high-chloride solutions, where it is resistant to pitting, crevice corrosion, and stress corrosion cracking. In contrast, 440c has poorer corrosion resistance, making it unsuitable for chloride environments. It’s commonly used for high hardness and wear-resistant applications such as bearings and cutting tools.
Hardness & Strength:
440c stainless steel is considered the hardest stainless steel with a Rockwell hardness of 58-60 HRC. Its hardness makes it ideal for making ball bearings, knives, and surgical instruments. 316, on the other hand, is softer than 440c and has a Rockwell hardness of 25 HRC only. Its lower hardness makes it more ductile and straightforward, making it suitable for manufacturing wire, sheet, and tubes.
Cost:
Compared to 316, 440c is a more expensive grade of stainless steel due to higher quantities of added carbon and chromium. Even though it’s more expensive, 440c’s unique hardness and wear-resistant properties make it a popular choice in applications demanding high performance and durability.
Applications:
316 is commonly used for marine equipment, chemical plants, and surgical instruments due to its excellent corrosion resistance properties. 440c, on the other hand, is perfect for manufacturing high-hardness products such as ball bearings, nozzles, and valves. It’s also used for making scalpels and surgical instruments due to its high strength and durability.
Conclusion:
In conclusion, 440c and 316 are useful grades of stainless steel with distinct properties. While 440c is hard and wear-resistant, 316 is ductile and corrosion-resistant, making them suitable for different applications. Ultimately, the choice between these grades of stainless steel depends on the specific application and its requirements. Knowing their differences helps you make a more informed decision and choose the best grade of stainless steel for your application.