420 stainless steel vs 304: What are the differences?

When choosing stainless steel materials, 420 stainless steel and 304 stainless steel are two common types. Many people may have doubts about the performance of these two materials. So which one is better, 420 stainless steel or 304 stainless steel? Are their differences obvious?
This article will analyze the performance differences of these two stainless steels in detail from multiple aspects.

What is stainless steel 420?

Stainless steel 420 is a type of stainless steel, a "cutting tool grade" martensitic steel, with certain wear resistance and corrosion resistance, high hardness, and its price is the lowest among stainless steel balls, suitable for working environments with ordinary requirements for stainless steel.
420 stainless steel is suitable for various precision machinery, bearings, electrical, equipment, instruments, meters, transportation vehicles, household appliances, etc. It is mostly used to manufacture parts that are resistant to corrosion by the atmosphere, water vapor, water and oxidizing acids.

What is stainless steel 304?
304 is a general-purpose stainless steel that is resistant to high temperatures of 800°C, has good processing performance and high toughness, and is widely used in industry, furniture decoration industry, and food and medical industry. The most important elements in 304 are Ni and Cr, but they are not limited to these two elements. Specific requirements are specified by product standards.

Which is better, 304 stainless steel or 420 stainless steel?
1.420 stainless steel and 304 stainless steel have different chemical compositions.
420 stainless steel contains more carbon and silicon, as well as a small amount of chromium and molybdenum. This makes it harder, more wear-resistant and more corrosion-resistant than 304 stainless steel. However, its plasticity is relatively low and it is difficult to process into complex shapes.
2.304 stainless steel has good corrosion resistance and heat resistance, 420 has high hardness, and 304 has better corrosion resistance than 402. 304 has good hot workability in stamping, bending, etc., and there is no heat treatment hardening phenomenon. 420 is a martensitic stainless steel, and 304 has higher plasticity than 420.
3.304 stainless steel has better processing performance and is easy to bend, stretch and weld. This is because the nickel content of 304 stainless steel is higher, which makes it have better plasticity. However, the processing performance of 420 stainless steel is relatively poor, and it is not easy to weld and bend.