Are Stainless Steel Screws Rust Proof?

Date Posted:

August 16, 2022

Post Author:

Marsh Fasteners

Last Updated on September 20, 2022 by Marsh Fasteners

When shopping around, you will have noticed that stainless steel screws come in at a rather higher price point. That’s not surprising considering that stainless steel usually costs three to four times the price of galvanized steel.

The top four reasons stainless steel fasteners remain such a popular choice include:

  1. Strength – how much load they will take.
  2. Durability – how long they will keep taking their designed load.
  3. Longevity – how often (or seldom in the case of ss screws) they need to be replaced
  4. Resistance to corrosion. Corrosion is a broad term describing the deterioration of a metal by oxidation or other chemical action. The orange-brown discoloration indicating corrosion of iron and iron alloys is called rust.

What Gives Stainless Steel its Rust Resistance Supremacy?

Before we go any further, let’s clear up a misconception. Platinum doesn’t corrode, rust, or tarnish. Other pure metals like gold and copper contain no iron, so they don’t rust. But copper, for example, does corrode.

Because stainless steel is an alloy containing iron-based metals, it is not strictly rust proof. However, its chromium content reacts with the oxygen to form protective properties that make stainless steel highly resistant to rust and other forms of corrosion. Moreover, this protective shield of chromium oxide re-forms if damaged.

The rust resistance supremacy of stainless steel screws results from the addition of chromium when the steel is in its molten state. This built-in fortification outperforms an outer layer of protection as found in galvanized screws.

Bear in mind that the grade of stainless steel affects its rust resistance. Austenitic stainless steel includes grades 18-8 (303 and 304), 305, and 316. These are listed in order of corrosion resistance, with 316 best suited to severe or marine environments – including if you live within 20 miles of a beach!

When Are Stainless Steel Screws Needed?

Just because stainless steel screws are super strong and resistant to rust and other corrosion does not mean that you have to use them.

Rust resistant stainless steel screws are meant for outdoor projects such as decks, sheds, and outdoor furniture.

Marsh Fasteners specializes in stainless steel products that are made to withstand extreme environments and resist rust and corrosion. For excellent pricing, service, and products – including stainless steel screws – contact us today.