What is the hardest metal in the world?

As a materials science expert with a focus on metallurgy, I can tell you that the concept of the "hardest metal" can be a bit misleading because hardness in metals is not a singular property but rather depends on the context in which the metal is used. However, when we talk about the hardest metal in a general sense, we often refer to the metal with the highest hardness on the Brinell hardness scale or the Vickers hardness scale.

The metal that is often cited as the hardest is chromium, which has a very high hardness and is used to硬化 (harden) steel. However, there are other materials that are even harder when considering composites or certain treatments. For instance, sapphire, which is a form of crystalline aluminum oxide (Al2O3), is extremely hard and is used in applications like watch faces and high-durability windows. Additionally, osmium is a metal that is very hard and dense, but it is not as commonly discussed in terms of general hardness.

It's important to note that while hardness is a valuable property, it is not the only factor to consider when selecting a metal for a particular application. Other properties such as tensile strength, ductility, and corrosion resistance are also critical.

The Strongest Natural Metal: Tungsten. As far as pure metals go, tungsten has the highest tensile strength, with an ultimate strength of 1510 megapascals. ... The Strongest Alloy: Steel. ... The Hardest Metal: Chromium. ... The Most Useful Strong Metal: Titanium.