Rust appears on 304 angle steel
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Why are there patches of rust on the surface of the newly ordered 304 angle steel? Were I tricked by JS? This post was last edited by Yan Yang Zhi Gang on 2009-4-6 21:08.]
If there is suspicion that the composition is not up to standard, a PMI test can be used. In fact, stainless steel is not truly rust-proof; its corrosion resistance depends entirely on a very thin passivation layer on its surface. To ensure the corrosion resistance of stainless steel, strict rules exist regarding its storage and transportation. The most common cause of rusting in stainless steel is contamination by carbon steel, such as when it is stored alongside carbon steel or when sparks from cutting carbon steel end up on it. First, check whether the surface of your stainless steel is clean.
If there is a lot of rust, it’s possible that there is a problem with the material and its quality is substandard. If it is to be used in applications with strict material requirements, it is necessary to request a material certification from the seller and to have samples tested for their material properties.
Rust may form whenever in contact with iron materials such as carbon steel. Either there are scratches from the transportation process; check whether the outer packaging is intact. An overly harsh storage environment, such as an acidic or alkaline atmosphere, can also cause rust. The safest approach is to conduct a PMI component spectroscopy analysis
It could be that the material does not meet the standards, or it might have undergone carburization due to contact with carbon steel.