Named for the colossal Titans of Greek mythology, titanium has the highest ratio of tensile strength to density of any metal on Earth. Titanium alloys (blends of titanium and other metals) boast the highest strength-to-weight ratio of any metal on the planet. Pure titanium is as strong as steel, but 45 percent lighter.
Titanium's impressive strength-to-weight ratio has made titanium alloys the go-to materials for airplane engines and bodies, rockets, missiles — any application where metal components need to be as tough and lightweight as possible. Although it's not a particularly rare metal, it is expensive because of the cost to mine and produce it.
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The Airbus A380, the largest passenger aircraft in the world, includes 77 tons (70 metric tons) of titanium, mostly in its massive engines.
Thanks to a metallurgical innovation in the 1930s called the "Knox process," commercial forging of titanium went into full swing in the 1940s and 1950s. The first application was in military aircraft and submarines (both American and Russian), and then commercial aircraft in the 1960s.
Way back in 1791, an amateur British mineralogist and church pastor William Gregor scooped up some curious black sand in a stream near the town of Cornwall. Some of the sand was magnetic, which Gregor determined was iron oxide, but the other material was a mystery. It was another oxide for sure, but not one on the books at the Royal Geological Society.
German chemist, Martin Heinrich Klaproth rediscovered the odd oxide in 1795 and gave it its mythological name, titanium oxide, after the deities that preceded the Olympians in Greek mythology
Even though it was discovered in the late 18th century, pure titanium wasn't isolated from its oxide until 1910, when American chemist Matthew Hunter, working for General Electric, figured out how to strip the silvery metal from its oxide under high heat and pressure in a sealed "bomb."
Corrosion is an electrochemical process that slowly destroys most metals over time. When metals are exposed to oxygen, either in the air or underwater, the oxygen snatches up electrons, creating what we call metal "oxides." One of the most common corrosive oxides is iron oxide, aka rust.
But not all oxides expose the underlying metal to corrosion. When titanium comes into contact with oxygen, it forms a thin layer of titanium dioxide (TiO2) on its surface. This oxide layer actually protects the underlying titanium from corrosion caused by most acids, alkalis, pollution and saltwater.
Titanium's natural anticorrosive properties make it the ideal material not only for aircraft, but also for undersea components that are exposed to highly corrosive saltwater. Ship propellers are almost always made from titanium, and so are the ship's internal ballast and piping systems, and onboard hardware exposed to seawater.
That same thin layer of titanium dioxide that protects titanium from corrosion also makes it the safest material to implant into the human body. Titanium is fully "biocompatible," which means it's nontoxic, nonallergenic and can even fuse with human tissue and bone.
Titanium is the surgical material of choice for bone and joint implants, cranial plates, the roots of dental implants, pegs for artificial eyes and ears, heart valves, spinal fusions and even urethral stints. Studies have shown that titanium implants trigger the body's immune system to grow bone directly on the titanium surface, a process called osseointegration.
Other reasons why titanium is the go-to for hip replacements and pins for fractured bones is that titanium has that famously high strength-to-weight ratio, which keeps implants lightweight, plus it exhibits the same exact elasticity as human bone.
As the price of pure titanium came down in the late 20th-century, manufacturers began looking for more commercial applications for this wonder metal. Titanium's lightweight strength made it a great fit for sporting goods.
The very first titanium golf clubs hit stores in the mid-1990s, including a giant driver from Callaway known as Great Big Bertha. The clubs were expensive compared to steel or wood drivers, but their success led other sports manufacturers to dabble in titanium.
Now you can find titanium in any piece of sports equipment where weight, strength and durability are key: tennis rackets, lacrosse sticks, skis, bicycle frames, baseball bats, hiking and mountain climbing equipment, camping gear and even horseshoes for professional racehorses.
Only 5 percent of the 6.3 million tons (5.7 million metric tons) of titanium produced every year is forged into metal. The vast majority is turned into titanium dioxide, the same material that naturally protects titanium from corrosion. Titanium dioxide is used worldwide as a nontoxic whitening pigment for paint, cosmetics, medicines and food, including white cake icing.
White paint used to be dyed with a lead-based pigment, but once the health effects of lead were known, titanium dioxide took over. It turns out that titanium-based pigments have some cool properties.
House painters choose titanium-based white paints because they are anticorrosive and last longer. Titanium oxide is extremely refractive, giving it a natural brilliance greater than a diamond and producing a particularly bright shade of white.
Titanium oxide also reflects infrared light, which is why titanium-based paints are always used on the exterior of solar observatories to disperse infrared light that blurs images.
Now That's Cool
The architect Frank Gehry chose titanium to wrap the exterior of the stunning Guggenheim Museum in Bilbao, which is sheathed in 33,000 titanium panels that shift in color and brilliance under different light conditions.
Ed. Jonathan Law and Richard Rennie. A Dictionary of Chemistry (8 ed.). 2020. (Oct. 10, 2023). https://www.oxfordreference.com/display/10.1093/acref/9780198841227.001.0001/acref-9780198841227
Deziel, Chris. "What Are the Top 10 Strongest Metals on Earth?" Sciencing. Mar. 13, 2018. (Oct. 10, 2023). https://sciencing.com/top-10-strongest-metals-earth-2595.html
"Mohs hardness." Encyclopedia Britannica. Sept. 15, 2023. (Oct. 10, 2023). https://www.britannica.com/science/Mohs-hardness
"Tensile strength." Encyclopedia Britannica. Sept. 22, 2023. (Oct. 10, 2023). https://www.britannica.com/science/tensile-strength.
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Today we are looking at the 10 strongest metals in the world. For obvious reasons, it is important for scientists, designers, and engineers to be aware of the properties of the many elemental metals and their myriad alloys.
The strength of a metal or alloy is determined by a number of properties and when choosing a metal it is important that the one chosen has the correct properties for the application, such as CNC Machining. For instance, for overall strength, nothing beats steel. If you want hardness then Tungsten is the one to go for and a close contender to both steel and tungsten, with properties close to both is Titanium.
Of course, Diamond is harder, and Graphene is tougher but we are limiting our list to the 10 strongest metals in the world.
When a material scientist speaks of ‘strength’ they are looking at a number of properties that define them as strong.
When we speak of tensile strength we are looking at the measurement of the force which would be required to pull something such as a cable, wire, rope, or a structural beam such as a girder to the point at which it breaks. The measurement is the maximum amount of stress before breaking, usually measured in pounds per square inch (PSI).
As an example, cookie dough has low tensile strength, and steel has high tensile strength.
This is a measure of how well the material resists being squeezed. In more basic terms it is the hardness of the material. This can also be measured in Psi. Another way to measure compressive strength is the use of the Mohs scale. On this scale of 0-10, 0 is the softest, and 10 is the hardest. Not surprisingly, diamonds are 10 on the scale. Compressive strength is an important property of tooling materials.
Yield strength refers to how well a beam made from a particular metal resists being bending and permanent deformation. This is a very important measurement for structural engineers. Metal will bend to a certain degree and this is the elastic state, a state when the metal will return to its original shape after being bent, a useful property of spring steels. Once the metal has reached the plastic state it has failed. This is measured in Mega Pascals (Mpa)
The ability of a material to resist impact without shattering. Going back to the diamond, it has a Mohs scale of 10 but can be shattered when struck with a hammer. Whereas steel can be struck with a hammer without shattering, the hammerhead itself is steel.
So now that we’ve looked at the properties let’s list the 10 strongest metals in the world. But first, let’s be clear, most of these ‘metals’ are in fact not classed as metals. Alloys are combinations of metals, and the main reason for making alloys is to produce a stronger material – see diagram below.
The most important alloy is steel, which is a combination of iron and carbon and is much harder than either of its two elemental components. Metallurgists create alloys of most metals, even steel, and they belong on lists of the hardest metals. We’ll go ahead and call all these metals as they are still composed primarily of elemental metals.
Diagram showing what makes an alloy stronger than pure metalThis alloy of Iron and Carbon (hence the name) has been with us for centuries. It is also a very widely used metal and we could indeed be said to be in the steel age. Carbon steel scores highly for all four of the properties which define strength.
Steel can be up to 1000 times stronger than iron
There are a few variations of this but in general mixing carbon steel with nickel increases the yield and tensile strength of this alloy to far above those of plain old carbon steel.
Iron and nickel are the most abundant metals in metallic meteorites and in the dense metal cores of planets such as Earth.
This is a special alloy of steel, chromium, and manganese. This mixing produces a corrosion-resistant metal with amazing properties, for instance, 304 stainless steel. Its properties make it good for Turning and Milling. You can check out all the stainless steel alloys we stock here.
If you have a chunk of stainless steel laying around, you can use it to de-stink your hands after chopping garlic and onions.
Known in the old days as Wolfram, this very special metal has the highest tensile strength of any naturally occurring metal. Not used often in its natural state as it is brittle and prone to shattering under the impact. That is why it is alloyed with other metals and alloys to create even stronger alloys.
Tungsten RingTungsten Carbide saw bladeTungsten Carbide machining toolsTungsten has the highest melting point of any of the metals at 6191.6 °F, to be exact.
As we explained above, tungsten is naturally very brittle, so it has to be alloyed with another material. Combining with Carbon produces Tungsten Carbide. The hardness of This material makes it ideal for use in tools with cutting edges, from common knives to circular saw blades to drill bits, and of course in the CNC machining industry.
The military uses tungsten to make bullets and missiles used in “kinetic bombardment.” This type of attack uses a super dense material to breach armor instead of explosives.
Often used in the aerospace industry due to being pound-for-pound, the strongest metal in the world. Pure titanium has a low yield strength of around 275 to 580 Mpa. It is therefore usually alloyed to produce stronger variations.
Titanium is the only element that will burn in pure nitrogen gas, no oxygen required.
This specialized alloy is also known as Gamma Titanium Aluminide is composed of Titanium, Aluminum, and Vanadium. Titanium aluminide alloys offer superior high-temperature performance with low weight for turbine blades and are as strong as nickel-based alloys, but at only half the weight.
Replacing the titanium turbine blades of a jet engine with an exact replica in titanium aluminide increases the thrust ratio because the engine is able to run over 300°F hotter.
You may have never heard of this alloy but this superalloy is one of the 10 strongest metals in the world. A mixture of Austenite, Nickle, and Chromium. It is a specialized alloy that keeps its strength in extreme conditions such as high temperatures. This ability makes it ideal for high-speed turbines and nuclear reactor applications.
Inconel® is a registered trademark of Special Metals Corporation.
This shiny, super hard metal is too brittle to be used by itself for many applications. It is therefore alloyed with other metals to make it harder. In its natural state, it is the hardest metal there is. Ideal for electroplating.
The weapons of the famous Terracotta Army of the Qin Dynasty in China were tipped with chromium deposits, which helped prevent tarnishing.
We left this particularly strong metal alloy for last. And for good reason, scientists are still experimenting with various magnesium alloys to create new alloys. This has already been termed the strongest and lightest metal there is. Lighter than Aluminum and stronger than titanium alloys. If the metal is used in cars it would automatically save 40% on fuel without any modification to the engine.
There are so many alloys being created that giving tensile or yield strength figures would be outdated within months. Just know this – pound-for-pound, there is nothing stronger.
Apple is reportedly working on its own magnesium alloy for use as the frame for their phones, laptops, and tablets.