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Shaanxi Xubo titanium metal technology co.,ltd, is situated in the prestigious China Titanium Valley, within the non-ferrous metal area of Gaoxin District in Baoji city, Shaanxi province. As a leading manufacturer, we specialize in the research, development, production, and service of premium tungsten materials, including Pure Tungsten, tungsten heavy alloy, molybdenum, tantalum, niobium, nitinol, and other innovative metal materials.
Committed to excellence and collaboration, we earnestly seek partnerships to achieve mutual growth and prosperity. At Xubo, we prioritize customer satisfaction and strive for win-win outcomes through our dedication to quality, innovation, and service excellence. Join us in shaping the future of tungsten materials and unlocking shared success in the global marketplace.
what is tungsten
Tungsten, with a density comparable to gold at 19.3 g/cm³ and hardness akin to diamond in tungsten carbide form, possesses unparalleled heat resistance, boasting a melting point of 3422 °C. These extraordinary characteristics make tungsten a highly sought-after metal in various industrial applications.
history of tungsten
Over 350 years ago, Chinese porcelain artisans introduced a distinctive peach color using a tungsten pigment, a novelty unknown to the Western world at the time. It wasn't until chemists in Europe, notably Peter Woulfe and Wilhelm Scheele, identified tungsten's presence in minerals from Sweden in the late 18th century, isolating its acidic white oxide and recognizing it as a new metal.
The credit for tungsten's discovery is attributed to Juan and Fausto Elhuyar, brothers with a keen interest in mineralogy, who successfully produced the same acidic metal oxide in 1783 at the Seminary in Vergara, Spain. Their groundbreaking work extended to the reduction of this oxide to tungsten metal through carbon heating, marking a pivotal moment in tungsten's scientific exploration.
Properties of tungsten
Tungsten, situated in the transitional group of the periodic table, exhibits multiple oxidation states ranging from +2 to +6. With an atomic number of 74 and a relative atomic mass of 183.84, it remains solid at room temperature due to its stable isometric crystal formation, observable under X-ray examination.
Its robust resistance to corrosion by most acids is a notable characteristic, although it can be susceptible to nitric acid and hydrofluoric acid. Additionally, alkaline oxidizing melts like potassium nitrate or sodium hydroxide can weaken its structure. At elevated temperatures, tungsten readily combines with oxygen to form trioxides, indicating its reactivity under specific conditions.
Naturally occurring tungsten consists of five stable isotopes: tungsten-180, tungsten-182, tungsten-183, tungsten-184, and tungsten-186, with varying compositions. These isotopes, present in differing percentages, contribute to the diverse properties and applications of tungsten across various industries.
Tungsten Physical Properties
Tungsten, in its purest state, presents as a lustrous white metal, though it carries trace amounts of oxygen and carbon, rendering it brittle under intense pressure.
As the densest engineering metal, tungsten boasts a remarkably high density of 19.25 g/cm³, owing to its compact crystal structure. Tungsten melting temperature is 3,140°C and tungsten boiling temperature 5,700°C, it surpasses other metals in thermal endurance.
Tungsten exhibits remarkable thermal stability with a low thermal expansion coefficient of 4.4×10-6mm°C, akin to borosilicate glass. This property finds utility in applications requiring glass-metal seals, showcasing tungsten's versatility and reliability in various industrial settings.
Tungsten Applications
Industrial field: Due to its high hardness, the addition of tungsten can significantly improve the strength, hardness and wear resistance of steel, which is an important alloying element widely used in the production of various steels, and its products are used in the production of a variety of tools, such as drills, milling cutters, as well as molds and so on;
Tungsten carbide has high wear resistance and refractoriness, and its hardness is close to diamond, so it is often used in the production of cemented carbide. Tungsten carbide-based cemented carbide is mainly used in the manufacture of cutting tools, mining tools and molds, etc. Tungsten is the refractory metal with the highest melting point and high hardness, so it is also often used in the manufacture of wear-resistant alloys, such as the valve of the aero-engine, the turbine blade and other wear-resistant parts;
Tungsten and other refractory metals (such as tantalum, niobium, molybdenum, rhenium) alloys have more excellent wear resistance, can be used for the production of rocket nozzles, engines, and other high heat strength parts; tungsten is also widely used in the manufacture of high specific gravity alloys, these high specific gravity alloys due to the high strength, high thermal conductivity, electrical conductivity, good processing performance, etc., often used in the manufacture of heat sinks, gate switches and other contact materials.
Electronics
Tungsten is widely used in the electronics and power supply industries because of its high plasticity, low evaporation rate, high melting point, and high electron-emitting ability. For example, tungsten filament has a high luminous rate and long service life, and it is commonly used in the manufacture of various bulb filaments, such as incandescent lamps, tungsten iodine lamps and so on. In addition, tungsten filament can also be used for the manufacture of electronic oscillator tube direct heat cathode and gate and various electronic instruments in the cathode heater.
Tungsten compounds are often used to produce certain types of paints, pigments, inks, lubricants and catalysts. For example, sodium tungstate is often used in the manufacture of metallic tungsten, tungstic acid and tungstate, as well as dyes, pigments, inks, electroplating, etc.; tungstic acid is often used as a mordant and dye in the textile industry, and is used as a catalyst for the production of high-octane gasoline in the chemical industry; tungsten disulphide is often used in organic synthesis, such as in the production of synthetic gasoline, as a solid lubricant and a catalyst; tungsten oxide, which has a bronze color, is used in paintings.
Medical field
Tungsten alloy is very suitable for medical applications such as X-ray and radiation protection due to its high hardness and density. Common tungsten alloy medical products include X-ray anodes, anti-scattering plates, radioactive containers and syringe shielding containers.
Advantages and Disadvantages of using Tungsten Metal
Resistance to High Temperature:Tungsten boasts the highest melting point among pure metals, reaching 3,244°C, enabling its utilization in high-temperature environments inaccessible to other metals.
High Density: With a density of 19 g/cm³, tungsten's microcrystalline shape facilitates its application in compact areas requiring significant mass.
Low Thermal Expansion: Tungsten exhibits minimal thermal expansion, ensuring stability at elevated temperatures, contrasting with steel's susceptibility to distortion.
Electronic Structure:Tungsten's conductivity and inertness make it ideal for high-radiation electronic devices and as electrodes in electrolytic applications.
Corrosion Resistance: Tungsten's remarkable resistance to corrosion allows its use in diverse environments, including marine settings, fishing lures, ship bases, and jewelry.
Fabrication Strengthening: Despite its robustness, tungsten can be drawn into thin wires without fracturing, exemplified by bulb filaments enduring high temperatures while maintaining functionality.
Disadvantages of Tungsten
Brittle Metal: Pure tungsten is exceptionally brittle, lacking flexibility or resilience. Its rigid structure makes it prone to breakage, rendering it unsuitable for applications requiring deformation or manipulation.
Health Concern: Inhaling tungsten particles can cause irritation to the respiratory system, posing health risks to individuals and environmental hazards if not properly managed.
Tungsten Costs: Due to its unique properties and high demand, tungsten remains a costly metal, with prices rising as demand increases, impacting industries reliant on its use.
Weight of Tungsten: Tungsten's dense nature contributes to its weightiness, posing challenges in applications where weight is a concern, such as jewelry or transportation of heavy machinery.
Economic Value: Unlike gold, which holds its value through recycling and resale, tungsten lacks resale value, making it an investment with limited potential for recouping costs.
Production of tungsten metal
Tungsten is extracted and purified from its ore in several stages. The ore is eventually turned into tungsten (VI) oxide (WO3) which is then heated up with a hydrogen or carbon fuel to produce a powdered form of tungsten. The tungsten can not be molded into ingots because it has a very high melting point and melting is rather not commercially feasible.
The powdered tungsten is therefore prepared by mixing it with small amounts of nickel or other precious metals and it is sintered. During the sintering procedure, the nickel diffuses and forms a tungsten alloy.
Tungsten can be extracted by hydrogen in the reduction of tungsten fluoride (WF6):
WF6 + 3H2 → W + 6HF
To manufacture tungsten products, the manufacturers start by sintering and at times molding the created tungsten alloys into billets of solid blocks or bars. These billets are then fabricated into tungsten foils, tungsten bars, tungsten plates, or tungsten sheets. This is done by grinding, drawing, die cutting, or molding. Some of its products require further processing.
Most tungsten products are sold for usage in three different conditions namely black, a form which retains its coating of lubricant, and oxide. The other form is the cleaned form in which the coating has been removed with the use of various chemicals. Lastly, there is the ground form in which the metal has been fortified with diamond silicon carbide machinery to remove the coating and obtain a specific smoothness and a desired diameter.
tungsten vs. tungsten Carbide
Tungsten is a chemical element, while tungsten carbide is a compound composed of tungsten and carbon. Tungsten carbide is known for its exceptional hardness and wear resistance, making it a widely used material for cutting tools, jewelry, and various industrial applications, whereas pure tungsten is often utilized in electrical and high-temperature applications due to its unique properties.
Many individuals confuse tungsten and tungsten carbide, with the latter being more commonly recognized. However, there are niche applications for pure tungsten. The following comparison contrasts tungsten and tungsten carbide, highlighting their distinct properties. Table 1 showcases various mechanical properties of each material, aiding in determining their respective applications. Note that mono tungsten carbide (WC) is utilized for this comparison, although other alloys also exist.
comparison of material properties between tungsten and tungsten carbide
| Material properties | Tungsten (Metric) | Tungsten (English) | Tungsten Carbide (Metric) | Tungsten Carbide (English) |
| Modulus of Elasticity | 400 GPa | 58000 ksi | 669-696 GPa | 97000-100000 ksi |
| Shear Modulus | 156 GPa | 22600 ksi | 260-298 GPa | 37700-43220 ksi |
| Tensile Yield strength | 350 MPa | 50800 psi | 140 MPa | 20300 psi |
| Thermal Conductivity | 163.3 W/m-K | 1133 BTU-in/hr-ft²-°F | 28-88 W/m-K | 194-610 BTU-in/hr-ft²-°F |
| Hardness (Rockwell A) | 66 | 66 | 90 | 90 |
Products Description
Tungsten, like other metals, exists in diverse forms and shapes to facilitate transportation and cater to customer requirements. These forms encompass bars, sheets, and foil, derived from the extraction process of tungsten ore. Additionally, tungsten alloys further diversify its applications, each alloy tailored to specific industrial processes and requirements.
Tungsten bars, comprising 99.9% pure tungsten powder, exhibit the metal's intrinsic properties, such as density and high-temperature resistance, irrespective of their shapes. These bars are available in various configurations and can be customized for specialized applications through alloying with six different metals.
Given its rarity, tungsten boasts a density akin to gold and surpasses lead's density by 1.7 times. However, crafting pure tungsten bars can be challenging due to its exceedingly high melting point of 3422°C (6191.6°F). Despite this, tungsten bars maintain remarkable stability, enduring exposure to water, air, or sulfuric acid, albeit oxidizing upon atmospheric contact.
Production of tungsten bars employs powder metallurgy, wherein tungsten ore undergoes reduction to fine powder and chemical processing to yield tungsten oxide. Subsequently, a heating process extracts pure tungsten from its oxide, which is then molded and sintered to enhance metal powder cohesion.
Once processed, tungsten bars are dispatched to manufacturers for various applications, including cathodes, wire, pins, electrodes, stainless steel additives, and heating elements. Producers strive to supply tungsten in suitable forms tailored to meet diverse customer needs.
Foil
Tungsten foil, a sleek metallic sheet, results from cold or hot rolling of tungsten sheets to attain desired thinness. Initially, tungsten bars are rolled to form flat sheets, further processed into foil, with vacuum annealing reinforcing the material. Stamped and drawn tungsten foil finds utility in high-temperature settings like heat shielding and semiconductors due to its thermal and electrical properties.
Typically ranging from 0.05 mm to 1 mm in thickness, tungsten foil boasts a purity of 99.9%, offering versatility in width, spanning from 100 mm to 400 mm. With a silver-gray hue and a melting point of 3410°C, it serves various industries, including electronics, medical, and energy, for applications like heating elements and current collectors.
Utilized in manufacturing electric light sources, medical shields, and heat shields, tungsten foil showcases exceptional resilience, boasting a density of 19.35g/cm³. Its adaptability extends to crafting tungsten evaporation boats, underscoring its significance across diverse industrial sectors.
Tungsten plate, akin to tungsten sheets and foil, is a flat tungsten piece crafted from tungsten powder. Its production involves extracting tungsten from ore, grinding it into pure powder, and molding it into plates through heat and pressure, followed by annealing for enhanced strength. Despite resembling tungsten sheets, plates differ by thickness.
Processing pure tungsten plates is intricate due to its exceedingly high melting point, demanding meticulous control to prevent damage. During rolling, heating rollers must align with specific conditions. Available in diverse sizes and thicknesses, typically cast, with options starting at 6.35mm, custom thicknesses cater to specialized applications.
Commonly used for shipping tungsten due to its convenience, tungsten plates find applications across industries like aerospace and electronics. Utilized in turbine blades and aircraft engine parts for its high melting point and strength, tungsten plates are instrumental in radiation protection materials for their density and resistance.
Industries rely on tungsten plates for their exceptional properties, employing them in various applications, from aerospace components to radiation shielding materials. Tungsten plates offer unparalleled strength and resistance, making them indispensable in critical sectors like aerospace and construction.
Rod
Tungsten rods, extruded cylindrical forms, vary in length and diameter based on intended application. Diverse shapes—round, square, rectangular, and more—suit different manufacturing needs. Despite their versatility, fabricating tungsten rods presents challenges due to its high melting point. However, their exceptional strength, durability, and corrosion resistance render them indispensable in engineering and industrial sectors.
Utilized extensively, tungsten rods excel in various industries for their unmatched wear resistance. Their versatility extends to cutting tools, offering superior performance over aluminum or steel counterparts. In medicine, tungsten rods find application in implants and procedures requiring exposure to extreme temperatures for sterilization. These rods stand as the preferred choice for manufacturing and industrial operations due to their enduring durability.
Critical in engineering designs, tungsten rods undergo machining, grinding, and forming to create diverse parts and products. Despite the difficulty in fabrication, their strength and resilience make them invaluable for repeated tool use. With applications ranging from cutting tools to medical implants, tungsten rods are indispensable in industries demanding high-performance materials.
Tungsten sheet, thicker than foil yet thinner than plate, is crafted from refined tungsten slabs. Distinguished by its thickness—ranging from 1.5 mm to 2.2 mm—it surpasses the dimensions of foil but falls short of plate classification. Its surface varies, appearing shiny, matte, or rolled, determined by manufacturing techniques and thickness.
Manufactured through isostatic pressing and sintering of high purity tungsten powder, sheets undergo deformation and heat treatment before being hot or cold rolled. This meticulous process yields versatile sheets suitable for diverse applications, from radiation protection to electronics and shipbuilding materials. Its unique properties make it a preferred choice over alternatives like lead, tantalum, and uranium, the latter two dismissed due to toxicity and expense, respectively.
Tungsten sheets find specialized use cases where their distinctive characteristics are essential. Despite alternatives like tantalum, tungsten's versatility and cost-effectiveness make it a preferred material. Its ability to shield against radiation and serve in electronics and construction underscores its significance across various industries, from aerospace to healthcare.
Tungsten metal processing
Powder metallurgy tungsten usually has fine grains, and its open billet is usually chosen to be forged and rolled at high temperature, and the temperature is generally controlled between 1500~1600℃. The tungsten material after billet opening can be further rolled, forged or rotary forged. Usually below the recrystallization temperature for pressure processing, this is because the recrystallized tungsten grain boundaries are brittle, limiting the processing performance, so with the increase in the total amount of tungsten processing, the deformation temperature is also reduced accordingly.
Tungsten rods and wires
The temperature of further forging of tungsten rods after billet opening is generally selected in the range of 1100~1400℃ according to the size of its deformation. The forging hammer is generally used for air hammer, rotary forging machine or other corresponding forms of forging, tungsten rods with a diameter of 3~60mm can be obtained by forging. The phenomenon of recrystallization is generally not allowed in the forging, and more than 80% of the finished bars need to be processed by forging to ensure the uniformity of the bar deformation, and stress relieving treatment is carried out at 1150℃.
Tungsten wires with a diameter of less than 3mm need to undergo single or multiple passes of tensile deformation on a drawing mold, and the pass-through heating and stress relieving method is generally chosen, with graphite emulsion as the lubricant.
In addition to tungsten wire, tungsten plates and strips are the most commonly used tungsten materials. Since tungsten has great deformation resistance and the deformation temperature is generally 1000~1400°C, the rolling mill generally requires a large enough rolling force. The rolls not only require high temperature resistance, but also must meet a certain high temperature strength. Therefore, it is very difficult to roll relatively wide tungsten plates.
When the blanked tungsten plate is processed again, as the processing volume increases, the processing temperature needs to be continuously lowered. When the total processing volume exceeds 90%, 200~600℃ can be used for processing, and the deformation of the processing pass is about 10%. . The total deformation is about 80% and requires stress relief annealing.
There are two production methods for tungsten strips: when the width of the tungsten strip is wide, it is usually produced by rolling foil and then cutting; when the width of the tungsten strip is small, cutting becomes very difficult. Direct rolling of strip from tungsten wire becomes a feasible method. Although the tungsten wire has undergone great deformation before rolling, it is still a brittle material and cannot be rolled at room temperature. Therefore, the heating method is still used to roll the strip from the wire. Heating generally involves direct electric heating. and indirect resistance furnace or gas heating. After reaching a certain amount of deformation, the tungsten strip needs appropriate stress relief and electrolytic polishing.
Tungsten cutting, stamping, welding and machining
After pressure processing, rods, wires, strips and plates need further processing to become qualified parts for use. These further processing methods include: cutting, stamping, bending, welding, polishing and certain machining. Considering the relatively high plastic-to-brittle transition temperature and high hardness of tungsten materials, the cutting, bending and stamping of tungsten materials require heating. As the thickness of the tungsten plate decreases, the corresponding processing temperature can be reduced.
Tungsten materials are commonly connected by riveting, bolting and welding. Welding is usually done in a vacuum or protective atmosphere box. Usually the welded part has coarse grains and is therefore more brittle than the base metal. Riveting and bolting are usually suitable for joining dissimilar metals, but once used at high temperatures, tungsten becomes recrystallized and brittle. In addition, tungsten materials are also suitable for certain brazing methods.
Mechanical processing of tungsten materials usually includes turning, milling, grinding and drilling. Because tungsten is brittle at room temperature and has high hardness, carbide tools are generally used for machining in the presence of coolant. It is worth mentioning that high-density tungsten alloys and tungsten alloys doped with rare earths are used for machining. Performance is greatly improved.
tungsten surface treatment
In most cases, the surface of tungsten materials needs to be treated. These treatments include mechanical treatments such as sandblasting, chemical treatments such as pickling, alkali cleaning and electrolytic polishing, as well as more complex treatments such as electroplating and vapor deposition. metallurgical process.
Conventional sandblasting, pickling, alkali cleaning and electrolytic polishing can significantly improve the surface finish of tungsten materials, and are also essential pre-processes for surface deposition or coating of tungsten materials. Depending on the usage requirements, sand blasting can be dry spraying or water spraying; pickling generally uses aqueous solutions of nitric acid and hydrofluoric acid; alkali washing is generally performed in molten sodium hydroxide solution.
why choose us
At Xubo, quality is paramount. Our commitment to excellence is evident in our ISO9001, SGS, and TUV certifications, along with stringent adherence to quality control protocols. We offer a comprehensive range of tungsten, molybdenum, tantalum, niobium, titanium, and nickel products, backed by professional technical consultation and customer service.
Dedicated to customer satisfaction, we provide comprehensive pre-sales, order tracking, and after-sales support. Our experienced team ensures punctual delivery, high performance, and attentive service. With a commitment to continuous improvement, we monitor production processes for at least 5 years, ensuring consistent quality and reliability in every product we supply.
FAQ
Q: Is pure tungsten expensive?
Q: Does pure tungsten rust?
Q: Is pure tungsten harder than steel?
Q: Is pure tungsten soft?
Q: Is tungsten carbide better than pure tungsten?
Q: Is tungsten a good Heat Conductor?
Q: What is tungsten thermal conductivity?
Q: What is the conductivity of tungsten?
As one of the leading tungsten manufacturers and suppliers in China, we warmly welcome you to buy or wholesale cheap tungsten in stock here from our factory. All customized products are with high quality and competitive price.
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