How to identify 304 stainless steel plate?
1. You can use a potion that is specially tested for stainless steel, such as 304 stainless steel. After the potion is tested, it will not change color within 1 to 3 minutes. For example, the 201 stainless steel plate will instantly turn dark brown-red after the potion test, the 202 stainless steel plate will turn to light brown-red within 5 seconds after the potion test, and the 301 stainless steel plate will turn into a light brick red within 1 to 2 minutes after the potion test. .
2. Use a special magnet to identify the 304 stainless steel plate. Because 304 stainless steel has a small magnetism, it can be distinguished according to the size of the magnetism. If the magnetism is too large, it should belong to 202 stainless steel.
3. You can also find relevant professionals to help in the identification, you can judge the authenticity of the 304 stainless steel plate from the surface color and smoothness of the plate.
The difference between 304 and 304L:
1. Chemical composition
The main components of 304 stainless steel and 304L stainless steel are both 18% chromium (Cr) and 8% nickel (Ni); their main difference is that 304L stainless steel is a low-carbon steel, 304L contains less carbon than 304, and 304L stainless steel contains The carbon content is less than 0.03; and the carbon content of 304 is less than 0.08. The “L” in 304L can be interpreted as ultra-low carbon.
304L is more corrosion resistant.
2. Welding
Under normal conditions, the corrosion resistance of 304L stainless steel is similar to that of 304 stainless steel, but after 304L welding or stress relief, its resistance to intergranular corrosion is excellent; it can also maintain good corrosion resistance without heat treatment. Temperature -196°C-800°C.
304 has a wide range of uses, with good corrosion resistance, heat resistance, low temperature strength and mechanical properties; it has good hot workability such as stamping and bending, and no heat treatment hardening phenomenon (non-magnetic, use temperature -196°C~800°C).
3. Price:
The price of 304L stainless steel is generally higher than that of 304 stainless steel.
4. Hardness
According to the hardness standard, 304 stainless steel is better than 304L stainless steel, because the level of carbon content directly affects the hardness of stainless steel. There is also 304H stainless steel series, H means high carbon content.