We have plenty of Hardest Materials which are naturally present in our environment and some are man-made. Most often, Diamond is considered to be the hardest material ever known, but there are some other materials as well which have snatched this title form the diamond.
So, here we present you the list of Top 10 Hardest Material in the World.
Chemically represented as Al2O3, alumina is common name for Aluminium oxide. Crystalline Polymorphous is the most common form of this chemical. Other varieties of this compound are ruby, sapphire etc. where color is due to some impurities. It is widely used for the extraction of Aluminium and as a refractory material due to its high melting point. It is water insoluble, resistive towards electricity and has high thermal conductivity. Due to its hardness it is used in cutting tools and as an abrasive.
9. Zirconium Carbide
Chemically represented as ZrC, zirconium carbide is a ceramic material which looks like grey metallic powder. Having high resistance towards corrosion and due to its hardness, it is extensively used in manufacturing cutting tools. It is formed by a strong lattice bond between Zr and carbon. It is extensively used in jet engines, rockets, vehicles etc. due to its load bearing capacity. Another common form of ZrC is used in coating the refractory in nuclear reactors.
8. Titanium Carbide
Chemically represented as TiC, titanium carbide is made from ceramic material and resembles tungsten carbide with appearance like black powder. It is widely used in preparing cermets which are used in high speed cutting of steel materials. It is resistive towards corrosion and getting oxidized. It melting point is 3160 degree Celsius, so it is used as a heat shield in space crafts and rockets. Moreover, if we add 6-30% more titanium, then the solution will be more brittle than original TiC.
7. Titanium Diboride
Chemically represented as TiB2, titanium diboride is a very hard ceramic substance. But it has good electrical conductivity and resistance to mechanical erosion. It has properties just like TiC but superior to them. It is three times harder than the fully hardened steel. Due to resistance to oxide, it is more stable than TiC and even pure iron. It is not a natural substance but prepared in laboratories using high temperature and pressure techniques.
6. Rhenium Diboride
Chemically represented as ReB2, it is the strongest man made compound. The synthetic compound is available at a very cheap rate due to low production prices but rhenium as a metal is very expensive. This compound was first synthesized in 1962. By the appearance, it resembles the black powder which is insoluble in water. In terms of hardness, it is comparable to the diamond. The reason behind its excessive hardness is the density of valance electron which is very high and the short covalent bond.
5. Boron Carbide
Chemically represented as B4C, boron carbide was found in 19th century. Due to its hardness, it is widely used in bullet-proof vests, tanks, armors and other industrial uses. It can easily absorb neutron radiation which makes it an ideal substance to use in nuclear plant shielding. It remains stable even in the ionizing radiations and other chemicals. It is also used in jet nozzles, resistant coating, brake linings, blasting nozzles and many more areas.
Chemically represented as CBN, Borazon is the commercial name for cubic boron nitride. It is available in abundance and cheap. Borozon is obtained by heating equal amount of boron and nitrogen at temperature more than 1800 degree Celsius. Being cheaper in price, they act as a substitute to the diamonds which are damn expensive. It is the reason that it used in making cutting tools, knifes, turbines, blades, saw blades, grinding steels, surgical knives, paper mill rolls etc.
They are made up of carbon atoms and under very high pressure for a very long time around 1 to 3.3 billion years. As they are formed under high pressure, so they are very hard in nature. The bonds between carbon atoms are unbreakable. Due to the hard nature, they are extensively used in for drilling, cutting, polishing and other fields. As they have a property to reflect and refract the light, so they are widely used in jewelry business as they look beautiful and shine as well.
Made from carbon atoms, Lonsdaleite is a translucent and brownish yellow in color. Several studies and simulations have shown that it can handle 585 more stress than diamonds. It is found naturally only when graphite containing meteoroids fall on the earth and hit the surface. So, due to this it is very rare in nature. As it is rare in nature, so many experiments are going on to make this material in the laboratories by some feasible ways.
1. Wurtzite Boron Nitride
The structure of this material is also just like diamond but it is made up of some other atoms instead of carbon. This material is also found naturally, so it cannot be wasted in the laboratories. It is formed during volcanic eruptions with high temperature and pressure. It is believed that it can handle 18% more stress than diamond can handle which is due to the re-orientation of the flexible bonds and the more complex structure than diamonds. After the re-orientation process, it becomes 80% harder than diamond. Thus, it is the strongest material present on the earth.
That is the Best Hardest Material on Earth “List”!.