What are the hardest metals

To determine which are the hardest metals, it is important, first, to know that strength is defined by several characteristics. It must also be said that none of these metals is as strong as diamond, but this carbon structure is not a metal.

So, in this blog post we tell you about the four determinants of a metal’s strength and which are the hardest.

Determinants of metal strength

When talking about the strength or hardness of a metal, we could be talking about these four properties:

1. Tensile strength. This is the maximum tensile stress that a body can withstand before breaking.
2. Compressive strength. This is the ability of a material to withstand loads that tend to reduce its size, in other words, to compress. It is opposed to tensile strength, which is defined as the ability to withstand loads that tend to elongate, resisting tension.
3. Impact strength. The ability of a material to resist impact without breaking.
4. Brinell hardness. This is a scale for measuring the hardness of a material by means of the indentation method, i.e. it consists of applying a constant force for a given time (10-30 seconds) using a tungsten carbide ball of 2.5 to 10 mm in diameter, measuring the penetration of an object in the material to be studied.

In this article we analyse which are the hardest according to the latter, the Brinell hardness.

What are the hardest metals

Tungsten

Tungsten is undoubtedly one of the hardest metals found in nature. It is known as a rare element, but once purified, it becomes more workable. It has a very high melting temperature of 3,422°C and an even higher boiling point of 5,930°C. It is often used to create alloys and alloy metals.

It is often used to create high-speed or hard alloys, such as high-speed steel, increasing its protection against abrasion and improving electrical conductivity.

Because it is the hardest metal, it is used to make the machining inserts with which all other metals, such as steel, bronze, etc., are processed and worked.

Iridium

Iridium is another metal with similar characteristics to tungsten, such as its resistance to melting and its high density. It belongs to the platinum group.

Its melting temperature exceeds 2,000°C, which makes it quite brittle. It is also one of the rarest elements on earth.

Steel

Steel is the first, but not the purest, hardest and strongest metal alloy. Because of the many variations and levels of quality that steel can take, there is no uniform hardness value.

Osmium

Osmium also belongs to the platinum group of metals, and has a high density, being the densest naturally occurring metal on earth. Moreover, it does not melt until it reaches a very high temperature of 3,033ºC, which makes it difficult to work with this metal.

When alloyed with other metals of the same group to which it belongs, it acquires great hardness and durability.

Chromium

Chromium is known for its scratch resistance. It is easier to handle compared to platinum group metals and is found in common alloys, such as steel. Chromium influences many properties of the final material and can be combined with other elements to modify them.

Titanium

Titanium is considered a very hard metal with an excellent strength-to-weight ratio. Even in its pure form, it is harder than some types of steel.

It can also be alloyed with other elements such as iron and carbon to create even stronger and more versatile metals.