There are a number of characteristics that might be desirable within a given steel or other metal product, and one of these is the “hardness” of the material in question. Referring to a few specific areas, but mainly how well the material resists forms of deformation, hardness is both important and sometimes hard to measure.

At Wasatch Steel, we’re happy to discuss the properties of any of our steel products with our Utah clients, including our steel bar, steel tube and numerous others. What exactly is metal hardness, why is it important, and what are the varying measures or scales used to track it? Here’s everything you need to know.

What is Metal Hardness?

Firstly, as we alluded to above, metal hardness refers to a characteristic of metal that describes how well it resists various forms of deformation and indentation. This is important because, in many cases, the hardness of a given metal will dictate how well it can be used for specific purposes.

For example, if you need a steel product that won’t scratch or dent easily, you’ll want to choose something with a high hardness rating. Conversely, if you need a material that can be easily manipulated or worked, you might want to select something with a lower hardness.

Of course, there are many other factors to consider when choosing a steel product, but hardness is definitely one of the more important ones.

Why is Metal Hardness Important?

As we just mentioned, hardness is important because it dictates how well a metal can resist various forms of deformation. This, in turn, affects the potential applications for that metal.

For example, if you need a steel product for an outdoor application, you’ll want to choose something that won’t rust easily. In this case, you’ll want to select a material with a high hardness rating so it can resist scratching and denting, as well as corrosion.

On the other hand, if you need a steel product for an indoor application, you might not be as concerned about hardness since the material won’t be exposed to the elements.

Why Measuring Steel Hardness Can Be Challenging

There’s some complexity involved in measuring steel or metal hardness, and the key reason behind this is the fact that hardness is not an intrinsic property of metal. That is, it can differ from one material sample to the next, even if those samples come from the same batch of metal.

In addition, hardness can be affected by a number of different factors, such as heat treatment, quenching, and more. As a result, it can be challenging to accurately measure and compare the hardness of different steel products.

That said, there are a few different measures used to find the hardness of a given metal. Our next few sections will go over these.

Mohs Hardness

One of the more familiar hardness scales is the Mohs hardness scale, which determines hardness based on surface wear. This involves a process of scratching a given metal with another object and observing the results.

The Mohs hardness scale runs from 1 to 10, with 1 being the softest and 10 being the hardest. For reference, Talc has a Mohs hardness of 1 while Diamonds have a hardness of 10.

Brinell Hardness

Another common method for measuring metal hardness is known as the Brinell hardness test. This involves using a steel ball to indent the surface of a metal sample and then measuring the resulting diameter of that indentation.

The Brinell hardness scale is generally used for metals that are too hard to be measured using the Mohs hardness test. It runs from HBW 10/3000 (very soft) to HBW 70/3000 (very hard).

Rockwell Hardness

The Rockwell hardness test is another popular method, and it’s often used for metals that are too hard to be measured using the Brinell hardness test. This test also involves indenting the surface of a metal sample, but instead of measuring the diameter of the resulting indentation, the depth is measured.

The Rockwell hardness scale runs from HRC 20 (very soft) to HRC 90 (very hard).

Vickers Hardness

Finally, the Vickers hardness test is another option for measuring metal hardness. This test involves using a diamond-tipped indenter to make an indent, or “impression,” in the surface of a metal sample. The resulting indentation is then measured using an optical microscope.

From here, a formula will be applied to calculate the Vickers hardness of the metal. The Vickers hardness scale runs from HV 10 (very soft) to HV 5000 (very hard).

Choosing the Ideal Measurement Format

There are several factors that you’ll need to consider when choosing the ideal hardness measure for your needs. These include:

– The type of metal you’re testing: Some measures are better suited for certain types of metal than others. For example, the Brinell hardness test is often used for cast iron and steels, while the Vickers hardness test is better for harder metals like titanium.

– The purpose of the testing: What are you trying to achieve with the testing? Are you looking to find the overall hardness of a given metal, or are you trying to identify any areas of weakness?

– The accuracy required: How precise does your measurement need to be? In some cases, a less accurate measure (such as the Mohs hardness test) will suffice, while in others, you’ll need a more precise measure (like the Vickers test).

For more on various measures of hardness in a given metal or steel material, or to learn about any of our steel products or services in Utah, speak to the team at Wasatch Steel today.