Are Stainless Steel Fasteners Truly Corrosion Proof?

Stainless steel fasteners are some of the most reliable and widely used fasteners in the business. From automotive to home appliances to space-age technology, stainless steel fasteners are essential for critical industries that our world relies on to function. That said, you might be wondering why stainless steel fasteners are so popular. You see them everywhere, but why do so many people rely on them every day? And on top of that—is their fabled corrosion resistance truly as reliable as people say? Well in this month’s blog post, we’re exploring how corrosion resistant stainless steel fasteners truly are.

In short: yes, stainless steel fasteners are corrosion resistant—and manufacturers rely on them every day. Corrosion weakens metals, reducing their load bearing capacity and weakening thread strength. As a result, corroded clips and fasteners loosen with time while simultaneously reducing resistance. Suffice it to say, clips and fasteners prone to corrosion are prone to failure.

With stainless steel fasteners, you can avoid this whole issue (or at least greatly postpone it). “Stainless steel” earns its name from its broad variety of corrosion resistant steel alloys, which include:

• Nickel
• Chromium
• Manganese
• Iron
• Titanium
• And many more

By changing the balance of these elements, the characteristics of the alloy are changed, creating stainless steel with different characteristics.

Well, yes and no. Theoretically, if you left a stainless steel fastener out on your porch and never interacted with it, it should remain corrosion resistant. Even if it forms a layer of rust, the chromium in it will react with oxygen to create a protective oxide layer on the steel’s surface. Internally, the steel would be perfectly fine—it might just not look as pretty.

In practice, however, stainless steel can meaningfully corrode. Improperly handling it or exposing it to certain elements can undermine the stainless steel’s corrosion “proof” properties. Let’s take a look at a few risk factors to watch out for:

Distortion. Because stainless steel has a low thermal conductivity but a high expansion rate, it’s fairly easy to distort during welding. This can also damage threading, so be careful. To prevent distortion during welding, we recommend low-amperage welding wherever possible and keep consistent interpass temperatures through the use of temperature indicating crayons.

Surface Contaminants. Surface contaminants such as iron filings, grease, and chalk can also interact negatively with stainless steel. Make sure to store your stainless steel fasteners separately from other fasteners and wash your hands before handling to reduce grease interactions.

Metallurgical Risks. Cutting your stainless steel components using Heat Affect Zone (HAZ) techniques will inherently create distortions and change in grade. Wherever possible, use shearing, manual cutting, or waterjet cutting. If none are viable, try to use laser cutting, which has the lowest HAZ of all thermal cutting techniques.

All in all, stainless steel is “technically” corrosion proof, but practically it will always rust with enough time and contamination.

At the end of the day, stainless steel fasteners are some of the most reliable on the market. If you need long-term solutions for your product, then stainless steel is one of the best materials to consider. To order your own stainless steel clips and fasteners, contact our team at All State Fastener today!