When most people think of corrosion, they think of rust. And while rust is certainly one type of corrosion, it's by no means the only one. In fact, corrosion can take many different forms, each with its own impact on a material's properties.
In this blog post, we'll discuss two specific properties that are affected by corrosion: ductility and tensile strength. We'll also look at how corrosion can lead to failure in metal structures and components.
Ductility
Ductility is a material's ability to deform under stress without breaking. This property is important because it allows metal structures to withstand loads that would otherwise cause them to fail.
However, corrosion can reduce a material's ductility by weakening its bonds and making it more brittle. This can lead to cracking and failure, especially in high-stress areas.
Tensile strength
Tensile strength is a measure of a material's breaking limit under tensile stress. More specifically, it’s the strength of attractive forces between the lattices and atoms that oppose any outside forces. This property keeps structures safe and reliable, and when affected by corrosion, structural integrity becomes compromised.
The effects of corrosion
Corrosion is a major problem in many industries, as it can weaken metal's ductility and tensile strength, leading to costly repairs and replacements. In some cases, corrosion can even be deadly, causing metal structures to collapse.
This chemical or electrochemical degradation of material is caused by the interaction of the material and the environment. Steel in particular corrodes when oxygen and an electrolyte (like saltwater) are present--which is pretty much unavoidable in marine applications.
The effects of corrosion can be seen in both uniform and pitting forms. Uniform corrosion is spread evenly over an entire surface, while pitting corrosion is localized.
Both types increase the brittleness of a material, increasing the danger of failure. Reduced cross-section and stress concentrations due to corrosion can have a significant negative impact on the material's load carrying capacity.
Fortunately, there are many ways to prevent corrosion, including coatings, passivation, sacrificial anodes, and corrosion-resistant alloys. The best method depends on the specific application and the environment in which the metal will be used. With proper prevention, corrosion can be controlled and metal structures can last for many years.
Corrosion can be tricky, but your offshore structure doesn't need to fall victim to it. Mark Tool's SplashTRON coating can be applied to various areas on an offshore platform, and is most commonly used to protect risers, j-tubes, spools, bends, and more from the corrosive elements of the splash zone. Contact us today to request a quote!