Also named tungsten heavy alloy, generally is refractory metal, which has two-phase composites consisting of W-Ni- Fe or W-Ni- Cu or even W-Ni-Cu-Fe, some tungsten alloys are added Co、Mo、Cr, etc. They have very high melting point and have a density twice that of steel and are more than 50% heavier than lead. Tungsten content in conventional heavy alloys varies from 90% to 97% and is the reason for their high density (between 16.5g/cc and 18.75 g/cc). Nickel, iron and copper serve as a binder matrix, which holds the brittle tungsten grains together and which makes tungsten alloys ductile and easy to machine. Nickel-iron is the most popular additive, in a ratio of 7Ni:3Fe or 8Ni:2Fe (weight ratio). The conventional processing route for tungsten heavy alloy includes mixing the desired amount of elemental powders, followed by cold pressing and liquid phase sintering to almost full density.
The matrix alloy melts and take tungsten into solution during liquid phase processing, resulting in a microstructure through large tungsten grains (20-60µm) which are dispersed in the matrix alloy. The as-sintered material is often subjected to thermo mechanical processing by swaging and swaging, which results in increased strength and high hardness.
The majority of current usages for WHAs (tungsten heavy alloy) are best satisfied with the W-Ni-Fe system. Alloys such as 93W-4.9Ni-2.1Fe and 95W-4Ni-1Fe represent common compositions. The addition of cobalt to a W-Ni-Fe alloy is a common approach for slight enhancement of both strength and ductility. The presence of cobalt within the alloy provides solid-solution strengthening of the binder and slightly enhanced tungsten-matrix interfacial strength. Cobalt additions of 5% to 15% of the nominal binder weight fraction are the most common.
Tungsten Heavy Alloy Main Application:
There are many kinds of tungsten heavy alloy products, different manufacture techniques could have various shapes, such as tungsten heavy alloy rod, cylinder, bar, block, brick, plate, tip, strip, sheet, ultra thin sheet, sphere, pellet, ball, disc, ring, tube, etc. They could be used in different fields depend on their special properties, such as small capacity but high density, high yield strength, good hardness, excellent elongation, etc.
When it comes to different functions, tungsten heavy alloy could be widely used for different industries and countries in various fields: such as the sports, including golf, fishing, darts, yacht, racing car; the medical, including radiation shielding, source holder, collimator, isotope container, nuclear syringe; the scientific, including tungsten heat sinks, oil drill, mine exploitation. Due to increasing abundant demand of Depleted Uranium, tungsten alloy is also widely used as a substitution in some parts of military products nowadays. As its high density similar to real gold, tungsten alloy material is very famous as gold-plated substitution. It could be made as gold-plated tungsten bar, golden tungsten brick, gold-plated tungsten bar, golden tungsten paperweight, gold-plated tungsten coin. For its high melting point, tungsten alloys are usually used for many high temperature working environments, such as rocket ignitron, turbine, etc. For its environment-friendly, tungsten alloy material is widely made as tungsten heavy alloy fishing sinker, jig, weights, it is much better than lead in small capacity but high density. Depending on special properties, tungsten heavy alloy is very popular in our life now.
Tungsten Alloy Sphere for Radioactive Waste Management:
Tungsten alloy, with high density of 17.0~18.5g/cm3, could also be made as the sphere for radioactive waste management. It could helpful for the temporary waste storage facilities, such as stainless steel drum as container, tungsten alloy sphere would be used as the radiation shielding by filling into the interlayer of the double wall of the stainless steel container, then the source of radiation from the radioactive waster would be shielded well inside the container. The diameter could be available as per clients’ requirement, even with the small diameter as 1mm.
Tungsten Alloy Military Defense:
Different process methods could offer different properties, if you need high ultimate tensile strength and high hardness, tungsten alloy material usually need to be swaged, which are usually used in military field, such as tungsten heavy alloy swaging rod for armor piercing, bullet and hunting shot, tungsten alloy fragments; if they need just sintering, they could be offered as tungsten alloy cube, sphere, ball, etc. for military defense. Sometimes, in order to get a higher property, we usually add some other materials to mix the powder, such as Co, Mo, etc. If it comes to some parts used for navy, coated or electrodeposited chromium could be offered according to protect from saltness corrosion.
Chinatungsten Online offers tungsten heavy alloy high-properties defense products as per military standard Mil-T-21014, or even could adjust some manufacture processes to meet a higher requirement for physical properties of hardness (42HRC min.), ultimate tensile strength (1400 MPa min.), yield strength(1300 MPa min.), elongation (8% min.), etc. Of course, if there is a need, Chinatungsten is willing to offer free standard testing rod for client evaluation before batch order.
Why not tungsten alloy?
Tungsten alloy product, which is a chemical compound that contains carbon and tungsten and is similar to titanium carbide. It was originally developed for use as a cutting tool, in machine tools applications, where it still finds widely use today. Cemented tungsten carbide is neither a metal nor a ceramic, which is prepared by reacting carbon and tungsten at a temperature of between 1400-2000ºC. With its highest hardness as 86~93 HRA (68~81HRC), however, it is not called tungsten alloy, but tungsten carbide, because its superior wear resistance and high cutting speed. Besides, as it is easy brickle, tungsten carbide is widely used as cutting blade, drill, bits, nozzles, etc. but for crack resistance, tungsten alloys are usually widely used as radiation shielding, crankshaft, counterweight, which are usually made of tungsten heavy alloy materil with its special properties as good elongation, small capacity with high density, good corrosion resistance, wonderful shock resistance, high radiation adsorption capability, etc.