Tungsten is a hard metal that has a number of interesting applications, including medical and defence. However, it’s also quite brittle and difficult to process with traditional manufacturing techniques like cnc.
A solution could be 3d printing, which allows for the creation of tungsten components with complex geometries that would be impossible to manufacture using other methods. Researchers at the Karlsruhe Institute of Technology (KIT) have adapted a standard additive manufacturing technique called electron beam melting, or EBM, to work with tungsten. Their work is published in the journal Acta Materialia.
The EBM method uses a scanning electron beam to melt metal powder layer by layer, resulting in a solid part with pressed features that need only minimal finishing. The KIT researchers’ key innovation was pre-heating the tungsten powder before applying the scanning electron beam, which reduces inherent stress and deformation in the metal and makes it easier to process.
The KIT team used EBM to create a series of tungsten parts, including a collimator that’s designed to direct radiation rays in medical accelerators. They found that SLM-produced tungsten collimators had attenuation properties comparable to those produced using lead metal, but were more durable and provided greater flexibility in terms of size and shape. The KIT research is a step towards the production of clinical-sized tungsten collimators. This, in turn, could lead to the development of more accurate x-ray imaging for diagnosis and treatment of cancers.