3D printed high-entropy alloys (HEAs) for hydrogen storage systems: characterization and evaluation of hydrogen embrittlement

The continuous development of conventionally fabricated high-entropy alloys (HEAs) has captivated the research community and satisfied the industrial perspective, owing to their enhanced properties resulting from the addition of alloying elements. Adopting advanced fabricating technology like 3D printing can expand the application scope of HEAs and reap the benefits of their improved properties, enabling the development of components suitable for critical sectors. Since the Industrial Revolution, 3D-printed HEAs have been an inspiring technology for producing industrial application-oriented components from pre-processing to post-processing. In as-built conditions, HEAs might get rid of defects better than regular as-built samples by lowering elemental segregation, porosity, residual stress, lack of fusion, and changes to the microstructure. The development of 3D-printed HEAs for hydrogen storage systems is underway. However, hydrogen embrittlement (HE) causes a continuous decrease in the performance of the materials and finally results in catastrophic failure. Adding alloying elements and multilayer coating are two ways to prevent this type of failure, which primarily occurs in the BCC crystal structure of the alloys. This paper talks about adding alloying elements to 3D printing to improve the HE. It stresses how important it is to find and reduce hydrogen embrittlement in 3D-printed parts used for hydrogen storage. This is especially important when looking at the mechanical properties like strength, ductility, corrosion, and fatigue in hydrogen-induced 3D printed parts.