Steel vs aluminum – comparison and main differences

Steel vs aluminum battle is not new – these two materials hold great importance, and not just in construction and manufacturing industries, but others as well. 

They are among the most commonly used metals in general, as there is countless number of items manufactured from these metals. From metal frames in construction to airplane fuselages, there is so many usages when it comes to these two metals. 

However, even though they do share some similarities in terms of appearance, they are also two very different metals, which is why this aluminium vs stainless steel battle makes very much sense, and here we will show you all the elements that differ. 

The main difference between aluminium and stainless steel

Speaking about the main difference between aluminium and steel – there isn’t just one. Both aluminium and steel are metals widely used across the industries, and for different types of projects and products, and in order to determine which of the two suits your needs beset, you need to be aware of every aspect they differ in.

For instance, aluminium represents an integral part of most automobiles, motorcycles, bicycles, aircrafts, and an important addition in moldings and trims of commercial buildings. Steel, on the other hand, is the mixture of iron and carbon, and therefore an important basis for production of many different types of steel, making it extremely versatile metal.

However, each of these materials boasts with a very distinct set of characteristics, that make it right or wrong in the light of your needs, so, in order to make this decision easier to make, let us take the look at the cost, corrosion resistance, strength, weight and couple of other important factors for selecting the right material.

Aluminum vs steel strength differences

What is stronger – aluminum or steel?

When it comes to strength properties, aluminum makes for a very desirable metal, as it is more malleable and elastic than steel. It is also very easy to shape, making it one of the most suitable materials for metal fabrication, thanks to its’ ability to form deeper or more intricate spinning.

This goes to show that aluminum is more light, malleable and ductile, able to be bent or extruded in variety of different shapes or profiles, without being cracking or breaking. 

So, is steel stronger than aluminium?

If we focus on shear aluminium strength vs steel strength – this is where steel takes the cake. It has a high amount of carbon, which makes it a very tough and resilient metal, but it generally can not be pushed to the same limits as aluminium, without suffering cracks or breaks.

Even though it’s considered to be less strong than steel, aluminum extensions can actually be made as strong as they need to be – for example, it serves very well in cold weather applications, as it becomes stronger as temperatures drop.

Aluminum vs steel weight differences

Speaking about aluminum vs steel weight – steel is known to be heavier and harder of the two, mainly thanks to before mentioned high concentration of carbon – the more carbon it contains, the heavier it will be. However, the plus side of having a heavy material is that is also a more durable material. 

This means that steel is less likely to warp, deform, bend, heat or force in any way, and in occasions where this matters, steel is truly an irreplaceable material. In addition to being much denser than aluminum, 2.5 times denser to be precise, and much more susceptible to cracking, there are much lighter forms of steel such as mild steel, that weigh less than carbon ones.

However, when it comes to mild steel vs aluminium discussion – even if it as light as aluminum, it still isn’t as strong, and isn’t much easier to handle. 

Steel roads pile

Aluminum vs stainless steel corrosion resistance

Here we have a clear winner or steel vs aluminum battle – aluminium.

Aluminium is a metal that is highly resistant to corrosion, without requiring additional treatments after it has been extruded – it doesn’t rust, doesn’t require coating or paint that can be scratched off, as it protected by its’ natural oxide film. It can also be further enhanced by a variety of different finishes, such as powder coating, brushed finish, painting, media blasting, polishing or other techniques. 

Steel however, if it’s’ not a stainless alloy, requires coating, painting or any kind of finish treatment in order to protect it from rust or corrosion, especially if it is located in an environment that is very wet, moits or abrasive in any way. 

Thermal conductivity of steel vs aluminum

When it comes to thermal conductivity, it is widely considered that aluminium is a much better conductor of heat than stainless steel is, which is why it is often used for air conditioning units and radiator manufacture.

However, not everything is so simple when it comes to thermal properties of these two metals, as stainless steel can actually be used at much higher temperatures than aluminium, that tends to become very soft in very high temperatures.

Steel vs aluminum electrical conductivity

Speaking about electrical conductivity, steel is one of the worst conductors of electricity among metals, while aluminium on the other hand, conducts electricity very well. Due to its’ lightweight, corrosion resistance and high conductance properties, it is usually used for the manufacture of high-voltage power lines.

Steel vs aluminum welding properties

When it comes to steel vs aluminum welding properties, even though aluminium is much easier to shape and extrude than steel, it doesn’t mean the same for the weling part. In fact, aluminium is much more difficult to weld than steel, depending on the type you choose.

Aluminum vs steel cost differences

Now, this is one of the most important factors when in determining what material to use.

When it comes to steel vs aluminum cost, steel is usually less expensive, but this mainly refers steel varieties like mild steel and carbon steel, as stainless steel tends to be much pricier than aluminum.

However, be aware that the price of metals fluctuates depending on the global supply and demand, fuel costs and ore availability. Another factor that very much determines the price is the cost of the raw material, so between the two identical spinnings of steel and aluminum, the aluminum on will almost always cost more because of the increase of the raw material price. 

The bottom line

Even though you might be tempted to go with a cheaper material, bear in mind that you need to weigh in all the factors we enlisted – do you need a more durable and strong material, or a material that is easier to extrude, shape or profile

Whatever it is you are looking for, never make a decision solely based on price, but rather consider your needs first and than select the most suitable material.