Metals That Don’t Rust
Metals That Don’t Rust or Are Corrosion Resistant
Metals are highly vulnerable to the damaging effects of rust and corrosion, which can compromise their strength and lead to costly and sometimes dangerous consequences. This blog post will explore what rust is and which metals are most effective when attempting to protect against corrosion. We will also discuss surface coatings, sealing processes, and other preventative measures.
What Makes Metal Rust?
Metal rusts when iron molecules in the metal react with oxygen and water molecules in the air. This process is known as oxidation, and it produces iron oxide, which has a reddish-brown color – commonly referred to as “rust”.
What’s the Difference Between Rust and Corrosion?
Rust and corrosion are two terms used to describe similar processes, yet they have very distinct differences.
Rust (a form of corrosion) is exclusive to iron or steel that has been exposed to oxygen and water. It appears as a reddish-brown coating on metal surfaces.
Corrosion, on the other hand, is the result of chemical reactions occurring between metal and their environment. This can occur when any metal reacts with oxygen, moisture, or other gases in its environment and results in a weakening of the metal’s structure due to oxidization.
What Metal Options are Corrosion Resistant?
- Stainless Steel (with additives)
- Copper, Bronze, and Brass
- Galvanized Steel (see external treatments)
Aluminum is the second most used material, right behind steel. Aluminum is often referred to as a “light metal” due to its very high level of strength compared to its weight.
Aluminum doesn’t contain iron therefore, it doesn’t rust. But it can still be affected by corrosion over time due to the ongoing presence of water, chemicals, salt, or other environmental issues.
How does aluminum protect itself? While chemical laws suggest aluminum should entirely dissolve when exposed to moisture—it has been used extensively for aircraft production since 1911 thanks to a unique property known as “passive oxidation,” which naturally forms an impermeable barrier between itself and external elements, effectively protecting against further degradation caused by weather or other factors.
Copper, Bronze, and Brass
Copper, Bronze, and Brass are three metals that remain shining through the ages.
Copper is known for its warm color that progresses to green over time due to the protective patina shield formed from oxidization to protect it from corrosion.
Bronze alloy combines copper, tin elements, and sometimes small percentages of other metals, making it more corrosion-resistant than pure copper. It doesn’t contain iron, so it will not rust, but on rare occasions, it could be susceptible to a destructive chemical process known as “bronze disease”, caused by chlorides forming under certain conditions such as submersion in saltwater.
Brass alloys are crafted using combinations of zinc and copper, creating yet another layer of durability while exuding sophisticated elegance wherever they may adorn. Certain Brass metals cost less than comparable copper or bronze materials. Brass is also smooth, malleable and an aesthetically pleasing color like gold.
Copper, Bronze, and Brass are widely used for architectural purposes. Check out our architectural wire mesh options.
Nickel and nickel alloys are non-ferrous metals with high strength and toughness, excellent corrosion resistance, and superior elevated temperature properties. Since nickel is less likely to expand when faced with high levels of heat applications, it is best used in high-temperature environments.
Some examples of nickel alloys include: C-276, Monel 400, Inconel 600 & 625, Incoloy 800 & 825, Nickel 200, 330 SS, and Alloy 20.
For rust-resistant materials (rather than rust-proof), alloys are a great option. Technically steel itself is an alloy, as it combines iron and carbon – but when adding other metals such as chromium and nickel to the mix, you can create various types of alloys that offer increased protection against rusting.
Some of these enhanced metal mixtures, such as stainless steel, provide more outstanding defense against oxidation over time and are manufactured to prevent rust completely.
Rust-resistant stainless steel is one of the most common alloys used to fight rust.
Certain stainless-steel products contain high levels of chromium which can prevent the formation of rust. The alloy creates a thin chromium oxide layer on the surface to protect itself. 304 and 316 are the most common of our stainless steel options.
Elements like nickel and molybdenum can also be mixed into stainless steel alloy resulting in Inconel alloy- giving you enhanced, top-of-the-line protection against oxidation and corrosive damage.
External Treating Methods
Below are the most common treatments to combat rust. See more information about the treatment and prevention of corrosion and rust.
Galvanized steel is a thin protective layer on carbon steel.
Galvanizing provides a layer of zinc coating, providing protection for iron and steel that is long-lasting and cost-effective. The zinc coating helps to slow corrosion by up to thirty times, safeguarding against rust build-up over time and acting as an extra layer between metal surfaces and their environment – ensuring long-term protection with minimal maintenance costs.
This crossover platform was fabricated to our client’s specifications and then galvanized for extra corrosive resistance.
Paint is a great way to protect metal objects from rust. While it isn’t a foolproof permanent fix, the right coat of paint can slow the formation of rust and give a pop of color to your project. An oil-based paint provides the best layer of defense, as it can adhere tightly and effectively resists moisture or contaminants over time.
But be careful: If there are welded joints or bolts on your object, already you’ll need to take extra precautions around those weak places for them to get good coverage with the protective coating. Doing so will create an effective barrier that works against corrosion, preventing further damage.
Fiberglass Grating, an Alternative Solution
Fiberglass grating (FRP) is a good solution when you are worried about rust. Available in molded, pultruded, and phenolic, FRP grating is a good lightweight, non-rusting solution. Marco Specialty Steel stocks a variety of fiberglass grating, structural shapes, ladder systems, crossover platforms, handrail systems, and stair tread products.
Your Supplier of Non-Rusting Specialty Metals
Marco Specialty Steel is a premier distributor and fabricator of FRP and metal products. Our expansive inventory includes a wide selection of “off the shelf” items in Carbon Steel, Stainless Steel, Aluminum, and Galvanized. However, our strength lies in our ability to provide not just the standard but the non-standard specialty steels. We regularly supply custom-manufactured and fabricated products for our customers in a wide variety of heat and heavy corrosion-resistant stainless steel and nickel alloys such as Monel 400, Nickel 200, 330-SS, and Inconel 600.
Contact us today to learn more about our vast product line.
We specialize in Wire Cloth, Perforated Metal, Expanded Metal, Bar Grating, Fiberglass Grating, Diamond Safety Grating, Perf Safety Grating, Tread Grip, and Hex Metal.