What Should be the Material of the Heating Element to be Used in Vacuum Furnace?

What Is A Vacuum Furnace?

A vacuum furnace is a type of heating equipment with lots of components used in a vacuum surrounding. Generally, it is composed of vacuum vessels, hot zones, pumping systems, cooling systems, and temperature & vacuum control systems. Among them, the hot zone is the heart of a vacuum furnace because it largely affects the process quality, the temperature, the pressure, and the operating cost.

Vacuum Furnace

What Are the Benefits of A Vacuum Furnace?

A reliable vacuum furnace comes with the following advantages.

  • Less Heat Loss: There is no air in the chamber, so there would be less heat loss caused by air convection. Additionally, the temperature in a vacuum furnace is well controlled within the hot zone.
  • Less Contamination: A vacuum furnace features low contamination by carbon, oxygen, and other gases since there is no air inside.
  • High Purity: The pumping systems remove low-temperature by-products, so we could get a higher purity end product.
  • Controlled Process: The process can be computer-controlled.

With these desired properties, vacuum furnaces are used to carry out heating processes such as annealing, sintering, brazing, hardening, and tempering.

Why Choose Molybdenum for Vacuum Furnace?

Molybdenum is used to manufacture vacuum furnace apparatus for the good points below.

  • High Melting Point: Molybdenum has a high melting point of 2,623 °C (4,753 °F). Only tantalum, tungsten, and carbon have higher melting points.
  • High Hardness at Elevated Temperature: Molybdenum is a strong grayish metal with a Mohs hardness of 5.5.
  • Perfect Thermal Properties: Molybdenum metal has high thermal conductivity, a low coefficient of expansion, and remarkable thermal shock resistance.
  • Great Resistance: This refractory metal is highly resistant to corrosion and creeps.

What is Tantalum Tungsten Alloy?

What is Tantalum Tungsten Alloy?

–Tungsten the Element

Tungsten the element (W, 74) is a Block D, Group 6, Period 6 metal element with an atomic weight of 183.84. It was found by Torbern Bergman in 1781. Tungsten has the highest melting point (3420℃) of all the metallic elements, and its density is about 1.7 times that of lead. This element is also famous for its high strength and melting point.

tantalum valuable

–Types of Tantalum Tungsten Alloy

The tantalum tungsten alloys have 3 variants according to their percentage of tungsten added. Ta2.5W, or tantaloy60, has 2.5% tungsten and 0.5% niobium. Ta7.5W, or tantaloy61, has 7.5% tungsten, while Ta10W possesses 10% tungsten and is also called tantaloy63. These alloys have a high melting point of 3005-3030 °C and a large density of 16.7-16.9 g/cm3.

–Tantalum Tungsten Alloy Applications

The application fields of tantalum tungsten alloys lie in the chemical processing industry and heater exchange industry. Similar to pure tantalum, these tantalum tungsten alloys keep useful features such as high melting point, tension resistance, and high corrosion resistance. An oxide layer is formed initially, and it is stable at temperatures below 260°C. This layer could stand strong hot acids like HCl and H2SO4. Because of great thermal conductivity, these alloys are also commonly found to make heat exchangers.

Comparison between Them

Pure tantalum and tantalum tungsten alloys have similarities and disparities in properties and application fields.

As for physical and chemical properties, pure metal and its alloys with tungsten content share some common points. They are strong materials withstanding high temperatures just like pure tantalum. More importantly, they have higher melting points and density, representing their higher strength. Here this article lists the detailed information as follows.

In terms of uses and applications, you can find them both used as chemical reaction pipes and heat changers. However, pure tantalum finds its special applications as capacitors and surgical implants. You’d better take budgets and efficiency into consideration since the tantalum tungsten alloy is a bit more costly but efficient than the pure tantalum.

Pure Tantalum VS. Tantalum Tungsten Alloy

What is Tantalum?

–Tantalum the Element

Tantalum the element (Ta, 73) is located in Block D, Group 5, Period 6 in the periodic table, and its atomic weight is 180.94788. This metal element was first discovered by Anders G. Ekeberg in 1802, yet pure tantalum was extracted by Werner von Bolton in 1903. Then, pure tantalum has been mainly mined from columbite-tantalite.

–Tantalum the Metal

Tantalum the metal is a typical refractory metal that is known for its high melting point and corrosion resistance. It looks lustrous gray-blue and has a melting point of 2980℃, which just falls after tungsten and rhenium. The density of pure tantalum is 16.4 g/cm3 and its elastic modulus is 185.7 GPa. All these figures indicate the thermal resistance and high strength of pure tantalum.

–Tantalum Applications

Because of these desirable mechanical and chemical properties, tantalum is applied to make lots of apparatus ranging from capacitors to reaction pipes.

First, nearly 50% to 70% pure tantalum contributes to the manufacturing of capacitors. A majority of capacitors are made from pure tantalum powers or wires. People choose this material because tantalum would form a passive oxide layer with dialectic strength. These capacitors could maintain ideal functions under high temperatures and high voltages. Additionally, tantalum capacitors are employed in the making of switches, mobile phones, fax machines, computers, automobiles, and even defense and military industries.

You can also find pure tantalum in the healthcare and medical field. Thanks to no immune response, the metal material is commonly used to make surgical implants. It can replace skull plates, connects torn nerves, or weaves abdominal muscle.

Pure tantalum could also be applied to make pipes for chemical reactions and heat exchangers for its unique corrosion and heat resistance ability. It can be generally found in the fields of aerospace and metallurgy.

What is Tantalum Tungsten Alloy?

–Tungsten the Element

Tungsten the element (W, 74) is a Block D, Group 6, Period 6 metal element with an atomic weight of 183.84. It was found by Torbern Bergman in 1781. Tungsten has the highest melting point (3420℃) of all the metallic elements, and its density is about 1.7 times that of lead. This element is also famous for its high strength and melting point.

–Types of Tantalum Tungsten Alloy

The tantalum tungsten alloys have 3 variants according to their percentage of tungsten added. Ta2.5W, or tantaloy60, has 2.5% tungsten and 0.5% niobium. Ta7.5W, or tantaloy61, has 7.5% tungsten, while Ta10W possesses 10% tungsten and is also called tantaloy63. These alloys have a high melting point of 3005-3030 °C and a large density of 16.7-16.9 g/cm3.

–Tantalum Tungsten Alloy Applications

The application fields of tantalum tungsten alloys lie in the chemical processing industry and heater exchange industry. Similar to pure tantalum, these tantalum tungsten alloys keep useful features such as high melting point, tension resistance, and high corrosion resistance. An oxide layer is formed on the surface and is stable at temperatures below 260°C. This layer could also stand strong hot acids like HCl and H2SO4. Because of great thermal conductivity, these alloys are also commonly found to make heat exchangers.

Comparison between Them

Pure tantalum and tantalum tungsten alloys have similarities and disparities in properties and application fields.

As for physical and chemical properties, pure tantalum metal and its alloys with tungsten content share some common points. Tantalum tungsten alloys are strong materials withstanding high temperatures just like pure tantalum. More importantly, they have higher melting points and density, representing their higher strength. Detailed information is listed as follows.

Table 1 Comparison between

Pure Tantalum and Tantalum Tungsten Alloy

  Ta W Ta2.5W Ta7.5W Ta10W
Melting Point (°C) 2980 3420 3005 3030 3025
Density (g/cm3) 16.4 19.24 16.7 16.8 16.8
Elastic Modulus (GPa) 185.7 N/A 195 205 200

In terms of uses and applications, you can find them both used as chemical reaction pipes and heat changers. However, pure tantalum finds its special applications as capacitors and surgical implants. You’d better take budgets and efficiency into consideration since the tantalum tungsten alloy is a bit more costly but efficient than the pure tantalum.

Is Tantalum The Same As Niobium?

What is tantalum?

Tantalum is a metal element, element symbol is Ta, its atomic number is 73, its density is 16.68g/cm, and its melting point is 2980 DEG C, which is the third most refractory metal. Pure tantalum has a blue color, and excellent ductility, and can be rolled into a very thin plate in the cold state without intermediate annealing.

tantalum

The corrosion resistance of tantalum is the same as that of glass. In the medium temperature (about 150 DEG C), only fluorine, hydrofluoric acid, sulfur trioxide, alkali, and some molten salts have an effect on tantalum. Tantalum is stable at room temperature, it will accelerate oxidation to produce Ta205 if heated to 500 DEG C.

Tantalum has a series of excellent properties such as high melting point, low vapor pressure, and cold processing performance, high chemical stability, anti-corrosion ability, constant liquid metal oxide film, has important applications in electronics, metallurgy, the chemical industry, iron and steel, hard alloy, atomic energy, superconducting technology, automotive electronics, aerospace, medical health and scientific research and other high-tech fields.
What is niobium?

What is Niobium?

Niobium is a rare high melting point metal. The melting point is 2467 degrees, the density is 8.6g/cm3, and the lattice type is body-centered cubic. The coefficient of linear expansion (0~100 C) is 7.1 x 10-6. Adding a small amount of niobium into a steel can greatly improve the strength of steel, improve the mechanical and welding properties of steel, and improve its corrosion resistance.

Niobium can be used as a capacitor and niobium-based superalloy. FS – 85 alloy is a structural material for the orbiting engine on the shuttle. C – 103 alloy can be used as a rocket nozzle material. Other niobium alloys, such as Nb – Zr, Nb – Ti, Nb – Ti – Ta, can be used as superconducting materials, and are widely used in magnetic resonance medical human images.

Niobium-based compounds and complexes can be used as catalysts to remove pollution, selective oxidation, and hydrogenation.

Is tantalum the same as niobium?

No. Tantalum and niobium are transition metals that are commonly found together in nature. They have very similar physical and chemical properties. Their properties of hardness, conductivity, and resistance to corrosion largely determine their primary uses today.
The reason for the similarity between niobium and tantalum is the size which is the result of the lanthanide contraction. Thus, the niobium and tantalum have the same size and due to the same size, tantalum and niobium have the same ionic and covalent radii.

Conclusion

Tantalum is chemically much like niobium because both have similar electronic configurations and because the radius of the tantalum ion is nearly the same as that of niobium as a result of the lanthanoid contraction. Niobium is a lustrous, gray, ductile metal with a high melting point, relatively low density, and superconductor properties. Tantalum is a dark blue-gray, dense, ductile, very hard, and easily fabricated metal. It is highly conductive to heat and electricity and renowned for its resistance to acidic corrosion.

Stanford Advanced Materials produce our tantalum products from the metal powder to the finished product. We only use the purest tantalum powder as the source material. This is how we can guarantee you a very high material purity.
We guarantee a purity of 99.95% for our sintered quality tantalum (metallic purity without Nb). The remaining portion is made up primarily of the following elements according to a chemical analysis:

Element Typical max. value
[μg/g]
Guaranteed max. value
[μg/g]
Fe 17 50
Mo 10 50
Nb 10 100
Ni 5 50
Si 10 50
Ti 1 10
W 20 50
C 11 50
H 2 15
N 5 50
O 81 150
Cd 5 10
Hg 1
Pb 5 10

Is Tantalum More Strong Than Tungsten?

What is tantalum?

Tantalum, a metallic element, is found mainly in tantalite and is symbiotic with niobium. Tantalum is moderately hard, and ductile and can be drawn into thin foil in the form of filaments. Its coefficient of thermal expansion is very small.

Tantalum has excellent chemical properties and is extremely resistant to corrosion. Although tantalum is highly resistant to corrosion, its corrosion resistance is due to the generation of a stable protective film of tantalum pentoxide (Ta2O5) on the surface. It does not react to hydrochloric acid or concentrated nitric acid, either under cold or hot conditions.

It can be used to make evaporating vessels, etc. It can also be used as electrodes for electronic tubes, rectifiers, and electrolytic capacitors. It is also used in medical treatment to make thin sheets or threads to mend damaged tissues.

An Overview of Ta Element

Chemical symbol Ta, gray metal, in the periodic table belongs to the VB group, atomic number 73, atomic weight 180.9479, body-centered cubic crystal, common chemical compound valence +5.

What is tungsten?

Tungsten (W) is one of the so-called transition metals with the atomic number 74. The shiny gray metal is in a solid state at room temperature.

Tungsten is characterized by special physical and chemical properties:
• Heat resistance: After carbon, tungsten has the highest melting point of all elements at 3422°C. It has a boiling point of around 5,700°C. With these properties, the metal can withstand high temperatures and smelting and in addition, has a very low coefficient of thermal expansion
• Density: 19.3 g/cm³; the density of tungsten is almost as high as that of gold in its pure state.
We prepare our tungsten to perform perfectly in its specific applications. We can determine the following properties through the addition of various alloys
• Machinability (such as cutting processes, formability, weldability)
• Microstructure and recrystallization behavior (recrystallization temperature, embrittlement, aging effects)
• Resistance: Tungsten also has high resistance to acids. Even hydrofluoric acid and aqua regia are hardly able to attack tungsten at room temperature
• Physical properties (such as melting point, vapor pressure, density, electrical conductivity, thermal conductivity, thermal expansion, heat capacity, and electron work function)
• Mechanical properties (such as strength, fracture behavior, creep resistance, and ductility)
• Chemical properties (corrosion resistance)

Is tantalum more strong than tungsten?

Tantalum is highly resistant to scratches and breakage and is extremely durable. Tantalum is therefore resistant to corrosion, and only if exposed to hydrofluoric acid it can corrode.

Unlike metals, such as tungsten, it is also shatterproof. This makes it great for individuals who lead active lives with busy hands.

Choose the Right Tantalum Foil for your Application

If you need a metal foil that can withstand high temperatures and has extremely strong chemical resistance to most corrosive environments then tantalum foil is already on your short list of materials.

ta metal foil

Tantalum belongs to a class of metals known as refractory metals, which are defined by their strong resistance to heat and wear. It has a melting point of 5,463 °F (2,996 °C), the fourth highest of all metals.

Like most metals, tantalum forms a thin but dense protective oxide layer (Ta2O5) when exposed to the atmosphere. This oxide layer firmly adheres to the surface of the metal, acting as a barrier that protects the underlying metal from further corrosion.

tantalum foil

Below are some examples of common applications for tantalum foils.

Included with each application are some suggestions based on how others in that industry specify the tantalum foils for such uses.  If your application is not on the list, we suggest contacting Stanford Advanced Materials’ technical sales at sales@samaterials.com.

 

Tantalum foils for Machined fasteners 

Tantalum fasteners are made of alternative materials prone to failure or that require expensive equipment shutdowns for maintenance. Tantalum foils appear in industries such as mining, energy, and pharmaceuticals as well as in metal and chemical processing.  For customers who prefer to make their own fasteners unannealed tantalum rod is most commonly requested.  Annealed tantalum foils are sometimes difficult to machine because the metal has a tendency to gum.  Unannealed tantalum foils make machining and threading easier.  As a service to our customers, Stanford Advanced Materials also offers machined fasteners to your custom sizes.

Tantalum foils for Vacuum furnace heating elements 

Because of tantalum’s oxidation resistance and high melting point, many vacuum furnace components incorporate tantalum foils. Grain-stabilized tantalum rod is designed to survive longer in high-temperature environments by reducing grain growth.  Stanford Advanced Materials can grain stabilize tantalum foils by producing the product using a powder metallurgy process which creates a very uniform and fine grain size or as an alternative the rods can be produced with very small amounts of additives such a Yttrium.  Either method prolongs or prevents the tantalum grains from growing and therefore increases machine life expectancy due to its ability to withstand high temperatures for long periods of time.

Tantalum foils for Machined parts for chemical processing equipment 

Tantalum foils have corrosion-resistant properties which make it a choice material for machined parts used in chemical processing equipment. Tantalum machined parts replace inferior materials that do not perform as well in harsh chemical environments and require extensive maintenance.  In most cases customer request tantalum 2.5% tungsten foil which has slightly more strength and corrosion resistance.  When ordering tantalum rods for such applications we suggest you order ASTM B365 R05200 for pure tantalum rods or ASTM B365 R05252 for tantalum 2.5% tungsten foils.

Tantalum foils for X-ray/radiation shielding

Due to its high density, tantalum’s radio-opaque qualities make it ideal for X-ray and shielding applications seeking to prevent radiation leakage. Tantalum foils are often manufactured into shielding which protects sensitive electronic components in aerospace structures as well as components operating in corrosive environments.  There is great variability in the tantalum foils used in applications such as this.  Because the shielding is due to tantalum’s density, which is intrinsic, just about any grade of tantalum foil will be functional.

Tantalum foils for Sputtering Targets for Gun Barrels

Tantalum foils are sometimes used as a sputtering target to coat the inside of gun barrels with tantalum as a replacement for chromium.  This makes the gun barrel manufacturing process more environmentally friendly and lets manufacturers reduce their ecological impact.  When purchasing tantalum for such an application most customers prefer tantalum foils that are fully annealed, melted in an electron beam furnace (ASTM B365 R05200), and have a 99.95% minimum purity.  Some customers have specified tantalum 2.5% tungsten or tantalum 10% tungsten foils.

 

Is Niobium Similar to Tantalum?

The answer is YES.

uses of tantalum niobium

Tantalum and niobium are inseparable in nature, why can’t they be used as a beautiful symbol of love?

Niobium and tantalum are in the same group in the periodic table and have very similar physical and chemical properties. They are often “inseparable” in nature, like a pair of “twin brothers”.

When niobium and tantalum were discovered in the early 19th century, they were thought to be one element, and it was only after about 42 years that they were separated for the first time by chemical analysis, and it became clear that they were two different metallic elements.

Tantalum (Ta) niobium (Nb) are high melting point (tantalum 2996 ° C, niobium 2468 ° C), high boiling point (tantalum 5427 ° C, niobium 5127 ° C) rare metals, the appearance of steel, gray-white luster, the Tantalum powder is dark gray, with gas absorption, corrosion resistance, superconductivity, unipolar conductivity and high strength at high temperatures, and other characteristics.

Therefore, the current tantalum niobium new material applications related to high-tech industrial fields include electronics, precision ceramics, and precision glass industry; electro-acoustic optical devices; cemented carbide, astronautics, and electronic energy industry; biomedical engineering; superconductivity industry; special steel and other industries.

Niobium-tantalum has good resistance to physiological corrosion and biocompatibility and does not interact with body tissues, so it is often used in the manufacture of bone plates, skull plate bone screws, dental implant roots, surgical appliances, etc. Tantalum is also known as a “biophilic metal” because it replaces bone in the human body with tantalum strips on which muscles can grow.

This is why they are also known as “pro-biological metals”. Therefore, there are no allergies when using them for rings, and the price is better. Because tantalum is almost twice as dense as niobium, a tantalum ring of the same size will be more textured, darker in color, and more expensive than a niobium ring.

Because they have always coexisted in nature, we can also define them as a good brother or a loving couple who are inseparable, if you want to buy a pair of rings you can consider buying one each of tantalum and niobium for better meaning.

What are the Uses of Tantalum?

The role and uses of tantalum

It can be drawn into thin tantalum foil in the form of a fine tantalum wire. Its coefficient of thermal expansion is very small.

uses of tantalum

Tantalum has excellent 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 tantalum 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 on its surface.

 

Chemical properties of tantalum

Tantalum has excellent chemical properties and is extremely resistant to corrosion, not reacting to hydrochloric acid, concentrated nitric acid, or “aqua regia” under both cold and hot conditions.

However, tantalum can be corroded in hot concentrated sulfuric acid. Below 150°C, tantalum will not be corroded by concentrated sulfuric acid, but will only react above this temperature.

In 175 degrees in the concentrated sulfuric acid for 1 year, the thickness of the corrosion is 0.0004 mm, tantalum into 200 degrees in the sulfuric acid soaked for a year, the surface layer is only damaged by 0.006 mm. At 250 degrees Celsius, the corrosion rate increases to 0.116 mm per year.

At 300 degrees, the rate of corrosion is accelerated, soaking 1 year, the surface was corroded 1.368 mm. In fuming sulfuric acid corrosion rate is more serious than in concentrated sulfuric acid, soaked in the solution at 130 degrees for 1 year, the surface was corroded by the thickness of 15.6 mm.

The Ultimate Guide to Tantalum

Tantalum, a metallic element, is found mainly in tantalite and 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 excellent chemical properties and is extremely resistant to corrosion.

tracing tantalum

Although tantalum is highly resistant to corrosion, its corrosion resistance is due to the generation of a stable protective film of tantalum pentoxide (Ta2O5) on the surface. It does not react to hydrochloric acid or concentrated nitric acid, either under cold or hot conditions. It can be used to make evaporating vessels, etc. It can also be used as electrodes for electronic tubes, rectifiers, and electrolytic capacitors. It is also used in medical treatment to make thin sheets or threads to mend damaged tissues.

 

Chemical symbol Ta, gray metal, in the periodic table belongs to the VB group, atomic number 73, atomic weight 180.9479, body-centered cubic crystal, common chemical compound valence +5.

Tantalum was discovered by the Swedish chemist A.G. Ekeberg in 1802 and named tantalum after the Greek mythological figure Tantalus (Tantalus). 1903, the German chemist W. von Bolton prepared the first plastic metal tantalum for use as filament material. 1940, large-capacity tantalum capacitors appeared and were widely used in military communications.

In 1940, large-capacity tantalum capacitors appeared and were widely used in military communications. During the Second World War, the demand for tantalum increased dramatically, and after the 1950s, the demand for tantalum rose year by year due to its expanding applications in the capacitor, high-temperature alloy, chemical, and atomic energy industries, promoting the development of research and production of tantalum extraction processes.

The hardness of tantalum is low and correlates with the oxygen content; ordinary pure tantalum, in its annealed state, has a Vickers hardness of only 140 HV. It has a melting point of 2995°C and ranks fifth among the monomers, after carbon, tungsten, rhenium, and osmium. Tantalum is ductile and can be drawn into thin foils of the filament type. Its coefficient of thermal expansion is very small. It expands by only 6.6 parts per million per degree Celsius. In addition, it is very ductile, more so than copper.

 

Tantalum Chemical properties.

Tantalum also has excellent chemical properties and is extremely resistant to corrosion, not reacting to hydrochloric acid, concentrated nitric acid or “aqua regia” under both cold and hot conditions. However, tantalum can be corroded in hot concentrated sulfuric acid. Below 150°C, tantalum will not be corroded by concentrated sulfuric acid, but will only react above this temperature. At 250 degrees, the rate of corrosion increased to 0.116 mm per year, and at 300 degrees, the rate of corrosion was accelerated, and the surface was corroded by 1.368 mm after 1 year of immersion.

In the fuming sulfuric acid (containing 15% SO3) corrosion rate is more serious than in concentrated sulfuric acid, soaked in the solution at 130 degrees for 1 year, the surface is corroded by a thickness of 15.6 mm.

Tantalum is also corroded by phosphoric acid at high temperatures, but the reaction generally occurs at 150 degrees or more, and the surface is corroded by 20 mm when immersed in 85% phosphoric acid at 250 degrees for 1 year. In addition, tantalum can be rapidly dissolved in a mixture of hydrofluoric acid and nitric acid, and can also be dissolved in hydrofluoric acid. But tantalum is more afraid of strong bases.

In a caustic soda solution with a concentration of 40% at 110 degrees, tantalum will be dissolved rapidly, and in a potassium hydroxide solution with the same concentration, it will be dissolved rapidly for as long as 100 degrees.

Except for the above-mentioned cases, general inorganic salts generally cannot corrode tantalum below 150 degrees. Experiments have shown that at room temperature, tantalum does not react to alkaline solutions, chlorine gas, bromine water, dilute sulfuric acid, and many other agents, but only to hydrofluoric acid and hot concentrated sulfuric acid. This is a relatively rare occurrence among metals.

 

Tantalum has properties that make it very versatile. In equipment for the production of various inorganic acids, tantalum can be used as a replacement for stainless steel, with a life expectancy several dozen times longer than that of stainless steel.

In addition, in the chemical, electronic and electrical industries, tantalum can replace the tasks that used to be undertaken by the precious metal platinum, making the costs required much lower. Tantalum is manufactured into capacitors equipped into military equipment.

The United States has an exceptionally developed military industry and is the world’s largest arms exporter. Half of the world’s tantalum production is used in the production of tantalum capacitors, and the U.S. Department of Defense Logistics Agency is the largest owner of tantalum, having at one time bought out one-third of the world’s tantalum powder.

 

 

Tantalum is one of the rare metal mineral resources and is a strategic raw material indispensable for the development of the electronics industry and space technology.

 

Tantalum and niobium have similar physicochemical properties and are therefore co-occurring in minerals in nature. The classification of tantalum or niobium ore is mainly based on the content of tantalum and niobium in the mineral, which is called niobium ore when the niobium content is high and tantalum ore when the tantalum content is high.

Niobium is mainly used in the manufacture of carbon steel, super alloys, high-strength low-alloy steel, stainless steel, heat-resistant steel and alloy steel; tantalum is mainly used in the production of electronic primary devices and alloys.

Tantalum and niobium minerals are complex in form and chemical composition, which in addition to tantalum and niobium, often also contain rare earth metals, titanium, zirconium, tungsten, uranium, thorium, and tin.

The main minerals of tantalum are tantalite [(Fe, Mn)(Ta, Nb)2O6], heavy tantalite (FeTa2O6), fine crystal [(Na, Ca)Ta2O6(O, OH, F)], and black rare gold ore [(Y, Ca, Ce, U, Th)(Nb, Ta, Ti)2O6], etc. The waste residue of tin refining contains tantalum, which is also an important resource of tantalum.

 

Rare Watchmaking Metal – Tantalum

Within the world of watchmaking, there has always been an unquenchable thirst for material innovation. Over the past few decades, the arms race of the age of the new materials has given rise to countless alloys, each surpassing the others in terms of strength and durability.

Big Bang Tantalum

Technology continues to advance, prompting us to desperately tap into the potential of the periodic table of elements in search of the next exotic metal that can replace gold and titanium.

Today let’s learn about a new metal material for space: tantalum. Tantalum, a chemical element with the symbol Ta and atomic number 73, takes its name “Tantalum” from the Greek myth of Tantalus. With a core mass of 16.7 g/cm3, tantalum has a similar weight to 18-carat gold. A hard, blue-gray, rare transition metal, tantalum has a much harder surface than other metals used in watchmaking, such as stainless steel, gold and titanium. It is extremely resistant to corrosion.

Tantalum is a refractory metal with a melting point of 3017 °C (boiling point 5458 °C), only tungsten, rhenium, osmium, and carbon have a higher melting point than it. It is often used as a secondary component of alloys. Tantalum’s low chemical activity makes it resistant to acid corrosion, and it is even resistant to aqua regia at temperatures below 150 °C. It is a suitable substitute for platinum as a material for laboratory equipment. It has a characteristic blue color that lurks beneath a lustrous silver-tone, providing an invisible luster that no other metal, not even titanium, can achieve.

Tantalum’s unique physicochemical properties are what attract high-end luxury watches. Imagine a watch that is almost heavier than gold or platinum, with a distinctive blue/gray hue, while staying away from the exaggerated nature of gold. And with no signs of aging corrosion over the years! This rare space metal has so far only found its way into the product lines of a few fine watchmaking brands.

The use of tantalum in the watch industry

The body of an OMEGA watch is titanium, and the bezel and central double link of the watch are tantalum. The two metals are easier to distinguish: titanium is gray with a slight yellow tint, while tantalum is darker with a blue tint.

The Hublot Big Bang Tantalum has been a staple of Hublot’s line since its launch in 2005, and although it has been re-imagined in a dozen different material and color combinations, the Tantalum variant tops the list. The grey timepiece has a diameter of 44.5 mm, a case, lugs and bezel made of the rare metal tantalum, and a brushed dial that displays the time, date and chronograph functions. As with most Big Bang, Hublot seamlessly blends contrasting materials, combining a rustic, soft tantalum watch with a black rubber strap.

Girard-Perregaux Bi-Axial Tantalum & Sapphire Tourbillon Girard-Perregaux first introduced its lightweight titanium tourbillon biaxial tourbillon just one year after its tantalum case was born – a stunning hand-wound mechanical piece whose distinctive look defined it.