Why Stainless Steel Automotive Parts are Ideal for Coastal Areas

Why Stainless Steel Automotive Parts are Ideal for Coastal Areas

Metals, in all their shapes, compositions and forms are present almost everywhere in our world. From construction materials to tools and machines, right through to those things that we come into contact with every day, like automotive components.
There is no doubting the importance placed on these various alloys and the roles they play in our daily lives. They literally hold our world together, shelter us and get us where we need to go.
Of course, wherever metals are used, for any reason, there are two particularly destructive challenges faced by them; these are the ravages of the onset of rust and galvanic corrosion; two conditions which have plagued metallic surfaces for a very long time.
This is particularly challenging for vehicle owners who may need to have these parts replaced when corrosion and rust undermines their structural integrity.
Fortunately, not all metals are created equal. When stainless steel pipes are used for automotive components, they imbue them with protection against these two very destructive factors.
So, let’s take a closer look at what exactly corrosion and rust is, and how stainless steel offers the perfect solution for keeping them away from your vehicles.
Galvanic Corrosion & Rust
To begin with, let’s explore the phenomena of galvanic corrosion and rust in a little more detail.
Each of these afflictions affect metals of nearly all types, with just a few alloys being able to withstand them both.
As each of them spreads unhindered through alloys, they result in them becoming brittle, unreliable, and more sensitive to damage.
But what exactly are they? How do they occur? How can you avoid their onset on your automotive components?
What is Galvanic Corrosion?
Galvanic corrosion is a process by which one metal corrodes another when the two come into contact with each other.
For the process to happen, there needs to be an electrical current running between the two, different alloys, as well as the presence of an electrolyte.
This electrolyte often comes in the form of water or moisture, which means that it is practically everywhere, and in many cases, is actually unavoidable.
This happens because different types of metal alloys have different electrochemical potentials. The more noble metal will act as the cathode, while the other that it has come into contact with, will act as an anode.
In such cases, the metal acting as the anode will begin to corrode much more rapidly than it would if it were by itself, while the metal acting as the cathode will have its rate of corrosion significantly slowed.
This, when left unchecked, will rapidly reduce the structural integrity of the metal acting as the anode, which will, eventually, leave it too damaged to be used.
What is Rust?
Rust or iron oxide has the potential to form in any alloy, such as steel, that contains quantities of iron. As the name would suggest, iron oxide is formed through the process of this particular metal going through a process of oxidisation.
There are three things that need to come into play for the creation of rust:
The metal in question needs to contain traces of iron
Since the process of rust is actually the oxidisation of iron molecules, the metal in question needs to contain this alloy in certain concentrations for rust to occur.
Oxygen needs to be present in the area for rust to form
The process of oxidisation requires one essential ingredient to occur, oxygen.
Of course (and thankfully for us) oxygen is just about everywhere; which means that just about any type of environment can present a danger of rust.
The area in question needs to contain significant levels of moisture
The third essential ingredient for the onset of rust is moisture, which enables the process of oxidisation to occur.
This is because when iron, oxygen and water come into contact, the process of rusting is greatly sped up due to a chemical reaction.
When these three elements are combined and left unchecked, the molecules of iron in the metal will start to oxidise, resulting in the spread of rust, which is just about as destructive to metal surfaces as galvanic corrosion is, since this process of oxidisation attacks the metal at the molecular level, weakening its bonds significantly.
Amplified Challenges in a Coastal Environment
There is a fourth compound that speeds up both the processes of rust and corrosion on metals, and that compound is sodium or salt.
When introduced into the mixture of moisture, oxygen and iron, salt can greatly increase the speed at which both rust and corrosion may occur.
For those living in dry, land-locked regions, this isn’t much of a concern, since moisture may only be present for limited amounts of time, and when it is, it generally doesn’t contain high levels of sodium, if any at all.
Of course, in such areas, rust and corrosion will still occur, it will just happen more slowly than in coastal areas.
For those people living and working in coastal regions, things are a little trickier.
In such climates, there is an abundance of moisture and salt in the air, which is generally bad news for metals in these areas; particularly those used in automotive components, since these are often used in the presence of an electrical current creating the difference between the cathode and the anode.
Have you ever noticed how cars and other metallic equipment tends to rust and corrode vastly more rapidly in coastal areas than they do in others?
The points mentioned above are the reason why.
Alloys that are Sensitive to Corrosion & Rust
As we have mentioned above, particularly where rust is concerned, there needs to be a presence of iron in the metal for corrosion to take place.
There are a startlingly high number of different types of metals that contain concentrations of iron just waiting to be oxidised.
This is because, in many instances, iron gives the alloys they are present in additional strength and ductility; which does, however, also put them at an increased risk of damage from rust or corrosion.
Let’s take a look at some of the most commonly used metals that, because of the presence of iron, are subject to rust and galvanic corrosion:
Aluminium
Aluminium is lightweight and actually quite resistant to corrosion.
That won’t stop it from behaving like a cathode when it comes into contact with another metal. So, while it may not corrode as quickly, the metal that becomes the anode upon contact, will.
When there is the presence of saltwater, however, aluminium tends to corrode quite rapidly, making it very badly suited for use in coastal areas.
Cast Iron
Cast iron holds a number of beneficial properties, including hardiness, ductility and elasticity; making it a widely used alloy all over the world.
It is, however, remarkably sensitive to oxidisation due to high concentrations of iron in its structure. In the right conditions, the rate at which cast iron rusts can be so rapid, that you can actually watch it happen.
In terms of galvanic corrosion, cast iron is surprisingly resilient (but not completely immune).
This is due to its high carbon content which normally sits between 3% and 3.7%.
This resilience is challenged, however, when cast-iron and a more noble metal come into contact in coastal environments.
Copper
Copper is also fairly resilient to corrosion, but that is only really due to its classification as a noble metal.
It will still cause corrosion on another, less noble alloy, however, when the two come into extended contact with one another; particularly when used in coastal areas where humidity and salt are present in high concentrations. In some situations, copper can still corrode however, in spite of its resistance.
On the upside, copper doesn’t really rust, not in the way that other alloys do.
Instead of the characteristic red oxidisation we see on metals such as iron, copper gives off a green tarnish when it rusts, due to the process removing electrons from the metal.
Brass
Brass does not typically contain any iron inside of its makeup, which also means that it does not rust. It does undergo a somewhat similar process, however, called dezincification.
Through this process, zinc present in the brass is destroyed, resulting in a porous type of copper.
But brass isn’t out of the woods yet, not when it is highly sensitive to corrosion.
This is because, by its very makeup, brass contains both anodes and cathodes in its makeup, since it contains zinc, copper and tin. When these come into contact with water, the process of corrosion becomes almost automatic.
Stainless Steel is Resistant to Corrosion & Rust
When it comes to the eternal conflict waged between metals, rust and galvanic corrosion, there is one alloy in particular that stands out against the rest due to its remarkable resistance to galvanic corrosion; stainless steel.
Widely regarded as one of the strongest and most resilient alloys, stainless steel is all but completely immune to the ravages of these two afflictions; so much so that it is often used for maritime projects where moisture and salt are present in incredibly high concentrations.
This, as you would imagine, makes it ideal for use in coastal areas, which is why stainless steel in Cape Town, Durban and other coastal areas, can often be found in abundance.
Stainless steel gets this resistance thanks to a thin oxide layer on its surface, thanks to the addition of chromium to the steel.
This layer is often referred to as the steel’s passive layer since it renders the alloy electrochemically passive, which means that it won’t react to corrosive elements.
Because of its chromium content, stainless steel is also resistant to rust, even though it does contain levels of iron.
The film created by the chromium as described above, also acts as a barrier that reduces the amount of oxygen that comes into contact with the base alloy. This, in turn, stops stainless steel from being able to rust.
Because of these remarkable properties presented by stainless steel, it is one of the most highly sought-after alloys for a range of manufacturing purposes. Where it is used to create stainless steel pipes for automotive components, stainless steel’s importance cannot be understated, particularly in coastal areas where vehicles suffer the ravages of corrosion and rust far more severely.
Contact Kwalkraft for Details
Stainless steel holds a number of remarkable properties that make it ideal for use in vehicles in just about any area.
It is incredibly strong, unbelievably ductile, has a diverse and comprehensive range of applications making it well suited to just about any use, and of course, is also very lightweight, making it ideal for use in high-performance vehicles.
Of course, its uses are not simply limited to automotive parts, it is widely used in manufacturing, in medical settings, in hospitality and even in construction.
Here at Kwalkraft, we are dedicated to producing top-quality automotive components and often use stainless steel as our not-so-secret ingredient to ensure their strength, resilience, lifespan and reliability.
If you would like to know more about our offers and services, be sure to get into contact with one of our representatives today, or visit our website for additional information.

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