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.

 

What Products is Tantalum Powder Used in?

Properties of Tantalum Powder

Tantalum powder is the powder state of tantalum metal. The chemical symbol Ta, a steel gray metal, belongs to the VB group in the periodic table, atomic number 73, atomic weight 180.9479, body-centered cubic crystal, common valence +5.

ta powder

Tantalum’s hardness is low and related to the amount of oxygen, ordinary pure tantalum, the annealed state of Vickers hardness is only 140HV .

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, even more so than copper.

What are the types of Tantalum metal powder?

Tantalum metal powder is generally divided into nano tantalum powder, micron tantalum powder, high purity tantalum powder, spherical tantalum powder, etc.”

How to Manufacture Tantalum Powder?

“To make materials, the key is to rely on technical precipitation and accumulation.” Talking about the development process of spherical tantalum powder, Stanford Advanced Materials has been developing the technology for nearly 10 years since 2009.”

What Products is Tantalum Powder Used in?

The manager took the staff on a tour of the generation to three generations of powder-making equipment, as well as the latest dedicated powder-making machine for refractory metals, “We completed a breakthrough in the core technology of aerosolization of filamentous materials in 2015 and have been iteratively developing according to changes in the market for cutting-edge applications, from nano-powders, conventional 3D printing micron powders to the current refractory metal powders. ”

“The biggest challenge in R&D is to match with market demand, SAM focuses on high-end fields and finds cutting-edge application scenarios. We successfully docked with a U.S. military-civilian integration institute to fit their needs and customize the product.” The manager came to the product center, and we finally saw the real face of this cutting-edge material.

When we first picked up the bottle of metal powder in our hands, we immediately felt that the powder was very heavy, and when we gently shook it, we felt the powder undulate and flow with it like water – this is the special tantalum powder for 3D printing made by Stanford Advanced Materials. “Our loose packing density is very high, reaching 9.84g/cm3, which is close to 60% of the density of tantalum metal block, so although the bottle is small, it still feels very heavy in the hand. At the same time, this powder flows very well, so you will feel like water, and flows very smoothly. On the other hand, the physical property of high sphericity in the particle size range of ultra-fine powder makes the powder have better dispersion and larger specific surface area, which makes the powder more stable and excellent to use.”

“During the R&D process, we overcame two major challenges: first, to ensure high sphericity with effective particle size control; second, to solidify the process to achieve stable and efficient industrial mass production.” The manager of Stanford Advanced Materials said, “We have explored and improved our own powder-making process and developed a new generation of special models; we have verified and standardized many aspects such as raw materials, process parameters, and operating procedures.”

Factors Affecting the Quality of Capacitor Grade Tantalum Powder

The powdered tantalum is dark gray or silver-gray, which is an important raw material for the preparation of capacitors and tantalum materials.

tantalum powder

The quality of capacitor grade tantalum powder used for manufacturing tantalum capacitor cores is mainly measured by its physical properties, chemical composition, and electrical properties.

Physical Properties

Physical properties mainly include average particle size, particle shape, fluidity and forming density. Low-pressure series products should have a small average particle size, complex grain shape, and low forming density, while high-pressure series products should have a large average particle size, simple grain shape, and high forming density. The fluidity determines whether tantalum powder can be formed by an automatic forming machine. Therefore, with the rapid increase in the production of small chip tantalum capacitors, great attention has been paid to the fluidity of tantalum powder.

Chemical Composition

The chemical composition has a direct effect on the electrical properties of tantalum powder. High impurity content, especially high content of phosphorus, boron, oxygen, carbon, potassium, sodium, and iron, will increase the leakage current and decrease the breakdown voltage of tantalum anodized film, so as to degrade the electrical properties of tantalum powder. However, the content of certain elements in tantalum powder is not as low as possible. It is found that adding certain selected elements can improve certain electrical properties of tantalum powder, and it has been proved that adding a small amount of phosphide to tantalum powder can inhibit the shrinkage of tantalum during sintering and thus increase the capacitance of tantalum powder by weight, while the breakdown voltage of tantalum powder can be increased by adding trace aluminum compounds with high dielectric strength.

Electrical properties

Electrical properties refer to the dc leakage current, breakdown voltage, and capacitance of the oxide film on the surface of tantalum anode after weighing, pressing, vacuum sintering, and anodizing of tantalum powder. All these properties are not only determined by the intrinsic characteristics of amorphous tantalum pentoxide anodized film but are also closely related to the physical properties and chemical composition of tantalum powder.

Please visit http://www.samaterials.com for more information.

How is the 3D Printing Tantalum Powder used in Biomedicine?

As a new manufacturing method for the global manufacturing industry, additive manufacturing caught the attention of the public six or seven years ago. And “3D printing”, a very down-to-earth and vivid name, was coined. Metal 3D printing is widely regarded as the most promising technology. Tantalum powder is an excellent biocompatible material, which has very strong biological inertia and corrosion resistance. Stanford Advanced Materials (SAM) has begun research on the application of 3D printing of tantalum powder in biomedicines such as hip joints.

medical ortho

Tantalum has a high boiling point, excellent resistance to corrosion, low coefficient of thermal expansion, and a high coefficient of capacitance, which has been used in electronic industries. SAM’s spherical tantalum powder is a good choice for 3d printing tech as it has high purity, uniform particle size, complete surface structure, easy dispersion, large specific surface area, and high surface activity.

SAM has successfully produced a biologically inert tantalum lattice structure and can have specific and random results. These structures follow the structural rigidity of human bones and can be well combined with bone cells so that the human body can excellently accept this kind of new tissue. SAM is dedicated to providing ultra-fine tantalum powder (D50=3um, D90<10um) for bio-applications. When used for additive manufacturing and selective laser melting, this type of ultra-fine tantalum powder can always maintain structural consistency. The final surface can also be further modified. The metal properties are still very stable.

SAM has successfully produced a biologically inert tantalum lattice structure and can have specific and random results. These structures follow the structural rigidity of human bones and can be well combined with bone cells so that the human body can excellently accept this kind of new tissue. SAM is dedicated to providing ultra-fine tantalum powder for bio-applications. When used for additive manufacturing and selective laser melting, this type of ultra-fine tantalum powder can always maintain structural consistency. The final surface can also be further modified. The metal properties are still very stable.

Please visit http://www.samaterials.com for more information.