The search for the world’s strongest material is never going to end.

Every device we use in our daily life use materials that have some amazing features that help them function. But all devices do not actually need the strongest material as well.

It’s normal for diamonds to come to your mind when you think of the strongest material in the world.

But is diamond the strongest?

No doubt diamond is strong but there are other materials that are stronger than diamond.

Let’s see which position diamond can make up in our list of 10 strongest materials to date.

Strongest Material
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10 Strongest Materials on Earth Till Date

Strength means an ability to withstand stress. A material is termed as strong if it can withstand a large value of stress without getting fractured. Recent developments in material science have introduced amazing materials which have a large value of tensile strength.

Some are very light hence their strength-to-weight ratios are very good and can surpass Kevlar and even diamond. So here is our list of 10 strongest materials.

10. Palladium Alloy Glass

Whenever we envisage glass, brittle nature comes to mind. But, this Palladium alloy glass is strong as well as tough, also much stronger than steel. Researchers from Caltech and Lawrence Berkeley National Laboratory were able to synthesize this material. This work was published in Nature Materials in January 2011.

This alloy is strong because of its property of shielding cracks. When defects in the amorphous structure become active under stress, they coalesce into slim bands, called shear bands. These bands propagate by sliding and introduce a large fracture toughness.

Although it is strong and has a large ultimate tensile strength (TS), its use is limited due to its expensive nature.

9. Ultra-High-Molecular-Weight Polyethylene (UHMWPE)

UHMWPE is a polymer fiber that is popular by the name Dyneema and Spectra. Both of these fibers are strong polyethylene derivatives. These fibers are stronger than the popular aramid fiber, Kevlar. They are almost 15 times stronger than steel.

Dyneema has a TS of 3.9 Giga Pascals (GPa). It possesses such strength from its molecular makeup, that a single molecule can contain a mass as high as 7.5 million hydrogen atoms. This enables them to take more stress by transferring load to such a long chain.

They are also resistant to moisture and extremely durable. So, these fibers are mostly used in making ropes for climbing, fishing, nets, etc. Due to their high strength, they are also used in armor.

8. Limpet Teeth

Limpet, a marine snail has teeth that are the strongest material and has a biological origin. It is made up of mineral-protein composite, an iron-based mineral called goethite laced out from protein. This material is nearly five times stronger than spider silk and has a TS of 5 GPa. They use these teeth to penetrate rocks to extract food from rocks.

7. Zylon

Zylon is a polymer material of liquid crystalline polyoxazole. This material has a TS of 5.8 GPa. It is used in making body armor and ropes used for various purposes. Although it is stronger, it is more likely to degrade. Its lifetime is nearly 30 months and hence it is not much popular as Dyneema and kevlar in the modern world.

6. Moissanite

Moissanite is a polymorph of Silicon Carbide. It was discovered by Henri Moissan, after whom it was named. It is held together by strong covalent bonds to which it owes its strength. It is very rare on Earth while its presence is found in meteorites.

Unlike other polymorphs of silicon carbide, it is strong and used as jewelry. Also, it is used in cutting tools and high-pressure experiments as a replacement for diamonds, since it is slightly less strong than diamonds. The TS value is 52.8 GPa.

5. Diamond

Diamond is one of an allotrope of carbon. It is found naturally, while synthetic diamonds can also be made in a laboratory.  It has a very compact cubic crystal structure without free electrons and each carbon forms four covalent bonds.

Theoretically diamond can be stronger than any of the materials presented here but the recorded TS of a diamond is 60 GPa. This is a large value but it is denser as compared to other fibers. And thus some people dictate that the aforementioned fibers are stronger than diamonds on the basis of the strength-to-weight ratio. But, diamond is a tough material.

4. Wurtzite Boron Nitride (w-BN)

Wurtzite boron nitride is one of the strongest materials found in the world. It has a hexagonal structure. Its theoretical TS is as high as 90 GPa, which is as close to that of bucky paper. However, it is yet to be proven. The limitations of the availability of w-BN make it difficult to prove. Meanwhile, it is still believed to be stronger material than diamond.

3. Lonsdaleite

Lonsdaleite also called hexagonal diamond is also an allotrope of carbon with a hexagonal lattice. The existing Lonsdaleite from meteorites and different diamond deposits show less strength than diamond but simulations show that it can be stronger than diamond.

Lonsdaleite is 58% stronger than diamond. This makes it the strongest material in terms of naturally existing ones. Although, someday w-BN may prove to be the strongest material due to its theoretical probability.

2. Carbon Nanotube Paper  (Bucky Paper)

Carbon nanotubes (CNTs) are made by rolling sheets of graphene. They are very strong individually. When these tubes are combined to form a paper, this paper is very strong. It has TS as high as 90 GPa. Pure CNT paper can be unquestionably the strongest material on Earth, with strength 500 times that of steel. But, the aggregation of such an amount is only possible by the introduction of defects. This decreases the strength of this paper.

This paper can be used in automobiles, armor, and space crafts. Its lightweight and astounding strength enable it to be used for various mechanical purposes.

1. Graphene

Graphene is a 2-Dimensional sheet of carbon, which forms graphite. It was isolated for the first time in 2004 at Manchester University by Andre Geim and Konstantin Novoselov. They won Nobel Prize for this outstanding discovery in 2010.

Graphene is extremely strong and the strongest material ever known. Although some people claim that carbyne (Linear acetylenic carbon) is the strongest material, it has not been synthesized in usable form to date. Only some thousands of atoms arrangement has been synthesized so it is not yet made.

Graphene, on the other hand, can be isolated and can sustain stress as high as 130 GPa. It has been used in many electronic devices and in improving the mechanical strength of other materials.

New materials are being synthesized and discovered as we advance in time. So, this list might need the addition of new materials in the future.

Ashwin Khadka is a PhD Scholar in Nano Energy and Thermofluid Lab in Korea University, Republic of Korea under Korean Government Scholarship Program. He has a Masters Degree in Physics from Tribhuvan University, Kathmandu, Nepal. He is a science enthusiast, researcher and writer.