Ten Metals with the Highest Melting Points on Earth!

Tungsten and tungsten wire bulbs have the highest melting points of all metals. In addition, do you know which metal elements have melting points?

highest melting points metal

This article will take a look at the top ten metals with the highest melting points.

Tungsten

Tungsten is a silvery-white metal shaped like steel. It has the highest melting point of any metal element, up to 3422°C, and a boiling point of 5927°C, making it the highest melting point in the world. It is an ultra-high temperature-resistant metal, ranking first in the list of metals with the highest melting points. As a rare high melting point metal, tungsten is commonly used as a lamp filament because when an electric lamp is turned on, the filament reaches temperatures of up to 3000°C. Only tungsten can withstand such high temperatures. In addition, tungsten increases the high-temperature hardness of steel. Meanwhile, tungsten is widely used in the alloy, electronic and chemical industries because of its high melting point, high hardness, high density, and good electrical conductivity. At present, more than 20 kinds of tungsten minerals and tungsten-bearing minerals have been found on the earth.

Rhenium

Rhenium is a silvery-white rare metal with a high melting point. It has the second highest melting point of all metals, second only to tungsten. Its melting point is as high as 3180℃ and its boiling point is 5900℃. Because of its high melting point, rhenium is more difficult to obtain than diamonds and is one of the rarest elements in the earth’s crust, making it very expensive and among the most expensive metals in the world. Rhenium and its alloys are widely used in the aerospace, electronics industry, petrochemicals, and other fields, especially in high-efficiency jet engines and rocket engines, and are therefore of great importance in military strategy.

high melting metal

Osmium

Osmium is a high-density rare metal, belonging to the heavy platinum group of metals, and is the world’s highest density metal. Osmium is found in osmium-iridium ores, which are extremely difficult to mine because of their density of 22.48 g/cm3, a high melting point of 3045°C, and a boiling point above 5027°C, making them one of the three metals with the highest melting points in the world. Osmium has a wide range of applications and can be used to make ultra-hard alloys. It is mainly used as a catalyst in the industry. It is often used to make products with other metals to extend their life.

Tantalum

Tantalum is a rare metal mineral resource found mainly in tantalite, which coexists with niobium. With a density of 16.68 g/cm³, a melting point of 2980°C, and a boiling point of 5425°C, it is the fourth most insoluble metal after tungsten, rhenium, and osmium. As a rare metal, tantalum has a high melting point, low vapor pressure, good cold processing performance, high chemical stability, and strong resistance to liquid metal corrosion, and has a wide range of application prospects. It has important applications in high-tech fields such as electronics, metallurgy, steel, chemical industry, cemented carbide, atomic energy, superconductivity technology, automotive electronics, aerospace, and medical and scientific research. Almost half of the world’s tantalum metal production is used to produce tantalum capacitors.

Molybdenum

Molybdenum is a transition metal element. It is an essential trace element for humans, animals, and plants. It is also the metal element with the highest melting point. It has a density of 10.2 g/cm³, a melting point of 2610°C, and a boiling point of 5560°C. Molybdenum is a silvery-white metal that is hard and tough. Like tungsten, it is a refractory and rare metal. According to worldwide molybdenum consumption statistics, molybdenum still occupies the most important position in the steel industry, accounting for about 80 percent of total molybdenum consumption, followed by the chemical industry, which accounts for about 10 percent. In addition, molybdenum is also used in medicine, agriculture, and electrical and electronic technology, which accounts for about 10 percent of total consumption.

Niobium

What metal has the highest melting point? Niobium is one of the metals with the highest melting point in the world. Niobium is a silvery gray, soft, and ductile rare high melting point metal with a density of 8.57 g/cm³, a melting point of 2477°C, and a boiling point of 4744°C. At room temperature, niobium does not react with air, but at high temperatures, it combines directly with sulfur, nitrogen, and carbon. Niobium has good superconductivity, corrosion resistance, high melting point, and wear resistance and is widely used in steel, superconducting materials, aerospace, electronics industry, medical, and other fields. Niobium does not occur in nature in its pure state but is combined with other elements to form minerals. Brazil and Canada are still the largest producers of niobium concentrates.

Iridium

Iridium is extremely chemically stable in acids and is insoluble in acids. It is the most corrosion-resistant metal and the metal material with the highest melting point. Its density is 22.56 g/cm³, melting point 2450°C, and boiling point 4130°C. The amount of iridium in the earth’s crust is 1/10 million. It is often dispersed in various ores of alluvial deposits and alluvial mines together with platinum-based elements. It is rare precious metal material and belongs to the platinum family of metals. Iridium can be used in a wide range of industrial and medical applications due to its high melting point, high hardness, and corrosion resistance.

Ruthenium

Ruthenium is one of the platinum group metals. It is the least abundant of the platinum group elements in the earth’s crust and the last of the platinum group elements. Ruthenium is a rare transition metal with stable properties and high corrosion resistance, with a melting point of 2310°C and a boiling point of 3900°C, making it the highest melting point metal material in the world. It has a variety of uses and is commonly used in electronics. It is cheaper than rhodium, has very similar properties, and is commonly used to produce electrical contacts, wires, and electrodes.

Hafnium

Hafnium is a shiny silver-gray transition metal with a density of 13.31 g/cm³, a melting point of 2233°C, and a boiling point of 4603°C. It is one of the metals with the highest melting point on earth and ranks ninth among the metals with the highest melting point. in 1925, the Swedish chemist Hedwig and the Dutch physicist Kost obtained pure hafnium salts by stepwise crystallization of fluorine-containing complex salts and reduction with sodium metal to obtain pure Hafnium metal. Hafnium is rarely found in the earth’s crust and usually coexists with zirconium. Hafnium is used as an atomic energy material, alloy material, high-temperature resistant material, electronic material, etc. because of its high-temperature resistance, oxidation resistance, corrosion resistance, ease of processing, rapid heat absorption, and exotherm.

Technetium

What is a high melting point metal? Technetium is one of the metals with the highest melting point on earth, with a melting point of 2157℃ and a boiling point of 4265℃. Technetium is also the first element prepared by artificial methods. It was first obtained by bombarding molybdenum with deuterium (heavy hydrogen) in a cyclotron. The element symbol is TC. it belongs to group VIIB of the periodic table and the element is a silvery-white metal. Technetium is used as a tracer in metallurgy, low-temperature chemistry, corrosion-resistant products, nuclear fuel burn-up measurements, and medical research.

Rhodium

Rhodium is a silvery-white, hard metal that belongs to the platinum family of elements. It is also the most expensive precious metal in the world and is extremely rare. Rhodium has a higher melting point than platinum, with a melting point of 1966°C and a boiling point of 3727°C. Rhodium is insoluble in most acids, has a high melting point, and is surprisingly resistant to corrosion. This silver metal is commonly used because of its reflective properties. In addition to making alloys, it is also used as a bright and hard coating for other metals. However, due to the high price of rhodium, it is usually used only as an additive element, except for special applications.

Vanadium

Vanadium is a silvery-white metal and has one of the highest melting points of any metallic element. With a melting point of 1890°C and a boiling point of 3380°C, it has the element symbol v and belongs to the VB group in the periodic table of elements. It is known as a refractory metal along with niobium, tantalum, tungsten, and molybdenum. Among the properties of vanadium, it rarely forms as a stand-alone mineral and is mainly found in vanadium-titanium magnetite. However, world reserves of vanadium and titanium magnetite are enormous and are concentrated in a few countries and regions such as Russia, South Africa, Australia, and the United States. Vanadium is widely used in the metallurgical, aerospace, chemical, and battery industries in the form of ferrovanadium, vanadium compounds, and vanadium metal.

Why is Tantalum So Expensive?

Because of the characteristics of tantalum such as good cold working and welding performance, tantalum has been used in electronics, semiconductor, chemical, machinery, aerospace, medical, and other industries.

tantalum metal

Why is Tantalum So Expensive?

Tantalum is a metal element with atomic number 73 and the chemical symbol Ta, the element corresponds to the steel gray metal, which has extremely high corrosion resistance, both in cold and hot conditions, and does not react to hydrochloric acid, concentrated nitric acid and “aqua regia”.

Tantalum is mainly found in tantalite and is symbiotic with niobium. Tantalum is moderately hard, ductile and can be drawn into thin foils of the filament type. Its coefficient of thermal expansion is very small.

Tantalum has very high chemical properties and is extremely resistant to corrosion. It can be used to make evaporating vessels, etc. It can also be used to make electrodes for electronic tubes, rectifiers and electrolytic capacitors. It is used medically to make thin sheets or threads to mend damaged tissue. Although tantalum is highly resistant to corrosion, its resistance to corrosion is due to the generation of a stable protective film of tantalum pentoxide (TaO) on its surface.

Smelting: Tantalum-niobium ores are often accompanied by a variety of metals, and the main steps in tantalum smelting are decomposition of the concentrate, purification and separation of tantalum and niobium to produce pure compounds of tantalum and niobium for the metal. Ore decomposition can be used hydrofluoric acid decomposition method, sodium hydroxide melting method and chlorination method, etc. Tantalum and niobium separation can be used solvent extraction method [commonly used extractants are methyl isobutyl ketone (MIBK), tributyl phosphate (TBP), secoctanol and acetamide, etc.], step-by-step crystallization method and ion exchange method.

Separation: First, the tantalum-niobium iron ore concentrate with hydrofluoric acid and sulfuric acid decomposition of tantalum and niobium is fluorotantalic acid and fluoronobotic acid dissolved in the leaching solution, while iron, manganese, titanium, tungsten, silicon and other associated elements are also dissolved in the leaching solution, forming a very complex composition of strong acidic solution. The tantalum-niobium leach solution is extracted with methyl isobutyl ketone and extracted into the organic phase at the same time. The pure organic phase containing tantalum-niobium is back-extracted with dilute sulfuric acid solution to obtain the organic phase containing tantalum.

Niobium and a small amount of tantalum enter the aqueous phase and then the tantalum is extracted with methyl isobutyl ketone to obtain a pure niobium-containing solution. The pure tantalum-containing organic phase is back-extracted with water to obtain a pure tantalum-containing solution.

The organic phase after the reverse extraction of tantalum is returned to the extraction cycle. Pure tantalum fluoride solution or pure niobium fluoride solution reacts with potassium fluoride or potassium chloride to form potassium tantalum fluoride (KTaF) and potassium niobium fluoride (KNbF) crystals, respectively, and can also react with ammonium hydroxide to form tantalum or niobium hydroxide precipitates.
Tantalum or niobium hydroxide is calcined at 900~1000°C to produce tantalum or niobium oxide.

Preparation of tantalum

Tantalum metal powder can be produced by the thermal reduction of metal (sodium thermal reduction) method. The reduction of potassium fluorotantalate with sodium metal in an inert atmosphere: K2TaF7+5Na─→Ta+5NaF+2KF. The reaction is carried out in a stainless steel tank, and the reduction reaction is completed rapidly when the temperature is heated to 900°C. The tantalum powder made by this method is irregular in particle shape and fine in size, which is suitable for making tantalum capacitors.

Tantalum metal powder can also be made by electrolysis of molten salt: using the molten salt of potassium fluorotantalate, potassium fluoride and potassium chloride mixture as the electrolyte to dissolve tantalum pentoxide (Ta2O5) in it, and electrolysis at 750℃, tantalum powder of 99.8~99.9% purity can be obtained.

Reduction of Ta2O5 with carbon heat can also be obtained from tantalum metal.

Reduction is generally carried out in two steps: first, a certain ratio of Ta2O5 and carbon mixture in the hydrogen atmosphere at 1800 ~ 2000 ℃ to make tantalum carbide (TaC), and then TaC and Ta2O5 in a certain ratio of the mixture of vacuum reduction into tantalum metal. Tantalum metal can also be produced by thermal decomposition or hydrogen reduction of tantalum chloride.

Dense tantalum metal can be prepared by vacuum arc, electron beam, plasma beam melting or powder metallurgy. High-purity tantalum single crystals are produced by crucible-free electron-beam regional melting.

Tantalum is a metallic element with an atomic number of 73 and the chemical symbol Ta, which corresponds to a steel-gray metal with extremely high resistance to corrosion, both in cold and hot conditions, and does not react to hydrochloric acid, concentrated nitric acid or “aqua regia”.

Tantalum is mainly found in tantalite, which is symbiotic with niobium. Tantalum is moderately hard, ductile and can be drawn into thin foil in the form of filaments. Its coefficient of thermal expansion is very small. Tantalum has very high chemical properties and is extremely resistant to corrosion. It can be used to make evaporating vessels, etc. It can also be used to make electrodes for electronic tubes, rectifiers and electrolytic capacitors.

It is used medically to make thin sheets or threads to mend damaged tissue. Although tantalum is highly resistant to corrosion, its resistance to corrosion is due to the generation of a stable protective film of tantalum pentoxide (TaO) on its surface.

What Products are Made of Tantalum?

Tantalum appears in many applications, including

– Sputtering barrels: Computer disk manufacturers and other industries that use sputtering processes are increasingly using tantalum to resist corrosion in sputtering barrels. The tantalum lining process is more environmentally friendly than chromium lining, helping the industry reduce its ecological impact.

tantalum

– Machined fasteners: Machined fasteners made from tantalum offer excellent corrosion resistance. They replace fasteners made from alternative materials that are prone to failure or require expensive equipment downtime for maintenance. Tantalum fasteners are found in industries such as mining, energy, and pharmaceuticals, as well as in metal and chemical processing.

– X-ray/radiation shielding: Tantalum’s radiopaque properties make it ideal for X-ray and shielding applications that seek to prevent radiation leakage. Tantalum shielding can also protect sensitive electronic components in aerospace structures as well as components operating in corrosive environments.

– Vacuum furnace heating elements: Many vacuum furnace components contain tantalum rods due to tantalum’s oxidation resistance and high melting point. Tantalum’s temperature particle stability increases the life expectancy of the machine, as it can withstand high temperatures for extended periods of time.

– Machined parts for chemical processing equipment: Tantalum’s corrosion-resistant properties make it the material of choice for machined parts for chemical processing equipment. Tantalum machined parts replace inferior materials that perform poorly in harsh chemical environments and require extensive maintenance.

 

The uses of tantalum

– 1: Tantalum carbide, used for cutting tools

– 2: Tantalum lithium, for surface acoustic waves, cell phone filters, hi-fi, and TV

– 3: Tantalum oxide, used in telescopes, cameras, lenses for cell phones and X-ray films, inkjet printers

– 4: Tantalum powder, used for tantalum capacitors in electronic circuits

– 5: Tantalum plate, used in chemical reaction equipment such as coating, valves, etc.

– 6: Tantalum wire, tantalum rod, used for repairing skeleton plates, suture frames, etc.

– 7: Tantalum ingots: used for sputtering targets, high-temperature alloys, computer hardware drive discs, and TOW-2 bomb-forming projectiles

 

Together with tungsten carbide WC and titanium carbide TIC, tantalum carbide TAC is a cemented carbide component used in cutting and drilling tools.

 

Tantalum is particularly suitable for heat exchangers; it has high thermal conductivity and its surface properties prevent the formation of adhesive deposits.

 

Manufacture of furnace components such as screens, supports, and crucibles. The alloying elements in high-temperature alloys increase high-temperature strength. It is biologically inert and can be used for implants, needles, etc. Yttrium tantalate YTAO4 is used in medical diagnostics.

 

SAM offers our customers a wide selection of tantalum rods, tubes, sheets, and wires, all designed for a variety of applications. Our products are cold rolled and annealed in a proprietary process to create machined parts with metallurgical properties ideal for applications such as sputtering gun tubes, processing into fasteners, X-ray radiation shielding, development rings, vacuum furnace heating elements, chlorinator springs, assemblies, and more for light bulbs or chemical processing equipment.

Tantalum Capacitors in the Military Industry

Why is tantalum so popular?

The most important use of tantalum is the manufacture of electronic components, especially capacitors. 50%-70% of the world’s tantalum is used to manufacture tantalum capacitors, mainly in the form of capacitor-grade tantalum powder and tantalum wire.
Because tantalum forms a dense, stable, amorphous oxide film with high dielectric strength on its surface, it forms a stable anodic oxide film in acidic electrolytes and is easy to process.

tantalum capacitors

At the same time, tantalum powder sintered blocks can obtain a large surface area in a small volume, so tantalum capacitors have a series of excellent properties such as high capacitance, low leakage current, and low equivalent series resistance, good high and low-temperature characteristics, and long service life.

Tantalum Capacitors in the Military Industry

A tantalum capacitor is called a tantalum electrolytic capacitor, which is also a kind of electrolytic capacitor, using tantalum metal as the dielectric, hence the name.

The tantalum capacitor was firstly developed by Bell Labs in 1956, and it is a passive component with a small volume and large capacity capacitor.

Tantalum capacitors’ downstream applications can be divided into two categories: military and civilian. The military field includes aviation, spaceflight, ships, weapons, and electronic countermeasures, while the civil field includes consumer electronics, industrial control, electric power equipment, new energy, communication equipment, rail transportation, medical electronics, and automotive electronics. As an essential basic electronic component in electronic circuits, capacitor products are widely used in the military and civilian fields.

Military capacitors are mainly ceramic capacitors and tantalum capacitors. The development of the military electronics industry is especially important in the context of the information-based military. It is widely used in communications, computers, automobiles, electrical appliances, aerospace, national defense, and other industrial and scientific sectors.