Which type of stainless steel will corrode away first, active or passive?

Active stainless steel will corrode away first compared to passive stainless steel. This is largely due to the structural differences in their protective layers. Active stainless steel has a compromised or disrupted protective chromium oxide layer, making it more susceptible to corrosion when exposed to harsh environments, moisture, or certain chemicals. This layer usually prevents corrosion by forming a barrier that protects the underlying metal from oxidizing.

In contrast, passive stainless steel has this protective oxide layer intact and functioning properly, which effectively protects it against corrosion. Therefore, in environments that promote corrosion, active stainless steel starts to deteriorate more quickly than passive stainless steel, making it the first to corrode. Understanding these differences is key for selecting materials in environments where corrosion resistance is critical, such as in commercial kitchens and food processing areas.