TUNGSTEN &

TUNGSTEN Alloys

Pure tungsten in wrought form — rod, bar, sheet, plate, foil, and wire — is produced by pressing and sintering tungsten powder followed by hot working (swaging, rolling, drawing) to achieve the desired shape and properties. Because tungsten cannot be melted and cast conventionally due to its extreme melting point of 3,422°C, all wrought tungsten products begin as powder metallurgy billets. Pure tungsten rod and sheet are essential for high-temperature furnace components (heating elements, radiation shields, crucibles), X-ray and gamma-ray shielding collimators, sputtering targets for semiconductor thin film deposition, TIG welding electrodes, and ion implantation components. Surplus pure tungsten in wrought form is among the most immediately tradeable tungsten material we broker, with buyers in semiconductor, medical imaging, and defense industries.

Tungsten wire is produced by repeated hot drawing of sintered tungsten rod through progressively smaller dies — a labor-intensive process requiring specialized equipment — which gives it exceptional tensile strength, particularly at fine diameters where it approaches the theoretical strength of tungsten. Non-sag (NS) or doped tungsten wire contains small additions of potassium, silicon, and aluminum which inhibit grain boundary migration at high temperatures, making it essential for lamp filaments that must survive thousands of thermal cycles. Fine tungsten wire (under 100 µm) is used in thermocouple assemblies, medical guidewires, orthopedic cable, dental applications, and scientific instruments. Heavy gauge tungsten wire serves as heating elements in high-vacuum furnaces. Surplus spooled tungsten wire is an active secondary market product across lighting, medical, and industrial sectors.

Tungsten heavy alloys (WHA) are produced by liquid-phase sintering tungsten powder, typically 90–97% W, with a nickel-iron or nickel-copper binder. The result is a dense, machinable tungsten-base material with densities ranging from approximately 16.85 to 18.85 g/cm³. Unlike pure tungsten, WHA can be machined more readily with conventional tooling, making it practical for complex-shaped parts, counterweights, shielding components, and precision ballast. ASTM B777 applies specifically to tungsten-base, high-density metal and defines four WHA classes by nominal tungsten content and density: Class 1 at approximately 90% W, Class 2 at 92.5% W, Class 3 at 95% W, and Class 4 at 97% W. Lower-density classes generally offer better machinability and toughness, while higher-density classes provide greater mass concentration and radiation attenuation. Magnetic W-Ni-Fe and non-magnetic W-Ni-Cu compositions address different application requirements. WHA is roughly twice the density of steel and significantly denser than lead, making it a common lead-replacement material for radiation shielding, ballast, and counterweight applications.

Tungsten carbide (WC) is produced by carburizing tungsten powder at high temperature and is the primary feedstock for cemented carbide — the world's most important hard material, used in cutting tool inserts, mining drill bits, wear-resistant components, and drawing dies. Cemented carbide consists of WC particles (typically 70–97% by weight) bonded with cobalt (3–25%) or nickel binder, sintered to a fully dense material of extraordinary hardness (Vickers hardness 1,400–2,000 HV). The tungsten carbide secondary materials market is one of the most active and well-established in refractory metals — WC scrap, swarf, and reclaim is recycled back into tungsten oxide and pure tungsten powder at dedicated recycling facilities. Buyers for WC-Co scrap include cemented carbide manufacturers, recyclers, and tungsten chemical producers.

Tungsten-copper composites are produced by infiltrating a sintered tungsten skeleton with molten copper, combining tungsten's thermal stability and low thermal expansion with copper's exceptional electrical and thermal conductivity. The result is a material that neither melts nor significantly deforms under the extreme heat and current loads of electrical discharge machining (EDM) electrodes, resistance spot welding tips, and high-power microwave window flanges. W-Cu is also the preferred heat sink material for power electronics modules where coefficient of thermal expansion (CTE) matching to silicon or gallium arsenide substrates is critical. Common compositions run from W70Cu30 (best conductivity) to W85Cu15 (highest density and hardness). Surplus W-Cu in rod, plate, and machined electrode form is produced by EDM shops, electronics manufacturers, and welding equipment producers.

Tungsten-rhenium (W-Re) alloys represent the pinnacle of refractory metal engineering. Adding rhenium to tungsten — through the "rhenium effect" — dramatically improves room-temperature ductility, raises the recrystallization temperature, and increases strength at ultra-high temperatures where no other material survives. W-Re wire pairs (typically W-3Re/W-25Re or W-5Re/W-26Re) form Type C and Type D thermocouples that measure temperatures from 0°C to 2,315°C in oxidizing and non-oxidizing atmospheres — used in rocket engine testing, nuclear reactors, glass furnaces, and crystal growth furnaces. W-Re sheet and rod are used in ion propulsion thruster grids, semiconductor crystal growth equipment, and advanced aerospace structural components. Rhenium's crustal abundance is approximately 1 part per billion (ppb) — making it one of the rarest elements in Earth's crust — and making W-Re alloys among the highest value-per-pound tungsten materials we broker.

Ferrotungsten is the primary alloying vehicle for introducing tungsten into steel melts, providing the controlled tungsten addition that gives high-speed tool steels (M2, M42, T1, T15), hot work die steels (H-series), and special structural steels their defining properties. Tungsten in steel increases hardness at elevated temperatures — the "red hardness" that allows high-speed steel cutting tools to retain their edge even when cutting generates significant heat. Standard ferrotungsten grades contain 70–80% tungsten with an iron balance, in broken lump form for addition to electric arc furnace heats. Surplus ferrotungsten from steel mill inventory reductions, reformulated melt schedules, or trading company positions is brokered to specialty steel producers and tool steel manufacturers who represent a consistent and active buyer base.

Tungsten powder — produced by hydrogen reduction of tungsten oxide — is the fundamental feedstock for all powder metallurgy tungsten products. Particle size and purity govern the application: coarse powder (10–30 µm FSSS) is used for pressing and sintering WHA and pure tungsten parts; fine powder (1–5 µm) is used for tungsten carbide production; ultra-fine and spherical powder grades serve thermal spray coatings, additive manufacturing, and metal injection molding. High-purity grades (99.99%+) serve semiconductor sputtering target production and specialty electronics. Surplus tungsten powder from closed sintering operations, reformulated powder metallurgy programs, or quality-rejected lots is of direct interest to sintering shops, carbide producers, and thermal spray applicators.