Cobalt alloys are widely used for their superior strength, hardness and corrosion resistance. They have many applications in a range of industries including aerospace, defense, medical, and energy.
Several types of cobalt alloys can be made from tungsten. These alloys include tungsten chromium cobalt (WCoTa), tungsten nickel iron (WNI) and tungsten and nickel iron cobalt alloys (WNIC).
WNCoTa is the preferred material for surface ablation in high-energy lasers to create tungsten carbide. Because the metal is very hard and has an extremely good fracture toughness, it is ideal for generating a highly dense and strong tungsten carbide.
WCoTa is also a preferred material for the manufacture of implantable devices because it does not produce nanoparticles that can be taken up through the skin or lungs. This material is produced from a powdered tungsten carbide to which metallic cobalt is added.
Some cobalt-based tungsten alloys are known to become embrittled when subjected to the annealing process. This embrittlement can make the alloy unsuitable for use in a wide variety of high-stress applications, such as kinetic energy penetrators.
Therefore, it would be desirable to have an alloy that can be sintered with minimal embrittlement. Moreover, it would be desirable to have an alloy with high strength and hardness but without the embrittlement caused by the cobalt.
These problems can be avoided by using a novel tungsten-nickel-iron-cobalt high density wrought alloy. The alloy has from 85-98% by weight tungsten and the remainder is a nickel-iron-cobalt binder.