How Much More Robust Is Aluminum Than Steel?

Aluminum isn’t usually the first material that comes to mind when considering strong materials, whether for a project or in casual conversation. Many associate aluminum with goods that aren’t precisely the epitome of strength, such as kitchen foil, beverage cans, and folding furniture.

On the other hand, if you’re looking for a robust material, steel will likely come to mind first. After all, steel is primarily used to construct ships, car frames, building support beams, and jail bars.

What is strength? Different Types of Strength Measurements in Materials

A material’s strength can be defined as its capacity to sustain a specified load, also known as force or stress, before it experiences particular areas of deformation or strain.

Yield Strength vs. Ultimate Strength

The maximum load a material can support before undergoing plastic (permanent) deformation is called the yield strength. All of the material’s deformation up to this stage can be undone by removing the load. Consider this similar to a rubber band that, when stretched, deforms without ever reaching its yield point because it returns to its previous shape as the tension is removed.

On the other hand, ultimate strength refers to the highest stress a material can sustain before failing or rupturing. Plastic deformation encompasses all of the deformations that take place between the yield strength and the maximum strength.

You can do this stress-strain test with a variety of applied forces. The most typical method involves pushing the material apart while providing tensile strength. This test allows us to ascertain a material’s ultimate tensile strength, the most common metric to compare strengths.

Different Aluminum Grades, Different Strengths

Aluminum’s ultimate tensile strength is a very changeable property. This is because aluminum comes in a wide range of grades depending on the alloying elements employed and in what proportions, each of which affects strength differently.

While pure aluminum, a relatively soft metal, is one of the weakest grades of aluminum, certain of its alloys can acquire significant strength.

Is Aluminum Strong Compared to Steel?

Many aluminum grades can be regarded as having extremely high strength, even matching some steel. Despite this, steel will typically be more robust when comparing samples of the same size of the strongest aluminum and steel alloys.

One of the strongest steel alloys, AISI 1080, has a maximum tensile strength of 965 MPa, whereas one of the strongest aluminum alloys, AA7068-T6, has an ultimate tensile strength of 710 MPa.

Aluminum alloys are considerably closer to steel than you may think if you compare strength-to-weight ratios, which is to say, how much strength each material contributes per weight. They can occasionally perform better than steel.

This demonstrates that selecting a material based solely on strength is not the best idea. Aluminum might be a better option if you need a strong material but are constrained by weight, whereas steel would be better if you are constrained mainly by space.

Don’t Examine Strength in a Vacuum

Steel is typically much more robust than aluminum when compared by volume and in a vacuum. However, strength is only one of many factors to consider when selecting a material for a project, and aluminum has several qualities that make it a competitive alternative to steel.

Similar Posts