Analysis of additively manufacturied refractory metals

Additive Manufacturing is a rapidly growing method for manufacturing components in a wide spectrum of UK industries. The sectors which have embraced AM, for example hydrogen energy and nuclear fusion, are limited by the absence of defect-free AM components when using metals such as refractory metals. Refractory metals are high cost materials used in military, electro vacuum, crucible, heating element, pinhole collimators and support hardware that either requires high strength, high heat tolerance, good corrosion resistance, radiation shielding properties or a combination of the four. However, refractory metals have very high density and high melting point (e.g. melting point of tungsten is 3422 deg C) which makes traditional methods of manufacturing, such as machining and casting, impractical. Furthermore, tungsten (W) is susceptible to cracking due to its high ductile-to-brittle transition temperature (DBTT). This makes testing of AM refractory materials using neutron tomography to characterise the internal structure of refractory metals key to the continued development, improvement of efficiencies, commercial viability, expansion and competitiveness in an open market for UK industry.