The exterior railing industry has always
said that 316-L stainless steel is the best material for oceanside
and corrosive environments. However, even 316-L has a potential to
corrode and rust over time. The one material that’s held up under the most
intense conditions is 2205 duplex. Stainless steel is made from a
mixture of metallic elements, each with its own level of corrosion resistance.
The steel industry describes these levels of durability with a rating
system called the pitting resistance equivalency number, aka PREN. A typical
PREN ranges from the mid-teens up to 40. With stainless steel, our previous go to,
316-L is in the mid 20s. In order to be fully corrosion resistant,
marine environments require a material that’s at least 32 on the PREN index.
Our 2205 duplex stainless steel on the other hand is rated from 34-35,
which well exceeds the requirements for marine environment corrosion resistance.
Duplex stainless has both the non corrosive properties of one type of
stainless and the strength of another, which is why the industry uses the name
duplex. It’s proven its strength and durability in structures like bridges
and oil rigs for the last half-century. That’s why we have adopted 2205 duplex
stainless for oceanside and corrosive environment.
Here’s a short version: you won’t have to worry about replacing your product ten
years down the road because 2205 stainless is made to last without ugly
corrosive decay. That’s why it’s used in some of the most extreme marine
environments and high-traffic structures around the world.
We’re so excited about the benefits this amazing material will bring to your
project. Are you interested in starting a project using 2205 stainless? Fill out
our design help form to get started.