Tungsten is a dense, strong metal that has many valuable applications, especially in the chemical industry due to its corrosion resistance. However, its hardness and extremely high melting point make it a difficult material to 3D print. In a paper titled "Influence of processing parameters on densification, microstructure and crystal structure during laser powder bed melting of pure tungsten," a team of researchers addressed these challenges.
The packing density and optically determined density of tungsten ranges from 94% to 98%, depending on process conditions, but the parts show microcracks and defects due to residual stresses on both micro and macro scales. Two types of tungsten samples were 3D printed for study and analyzed using scanning electron microscopy. Although the parts were prone to cracking, the researchers determined that the density and quality of the samples produced during the 3D printing process were high enough for use in medical radiation shielding and nuclear imaging, among other plasma-oriented environments. They also concluded that the parameters of laser powder bed fusion can be tailored to create 3D printed tungsten parts with relatively high densities.
3D printing tungsten could provide new applications for the material as it can produce parts with high precision and complexity. Other researchers have studied 3D printing tungsten before, and 3D printed tungsten components have even been commercialized. Despite the challenges, tungsten has proven itself to be a valuable 3D printing material, and many experts are particularly interested in its heat-resistant properties. In 2018, Guangdong Yinna completed a printing process test for 3D printing spherical tungsten powder.