Experimental Study on the Porosity of Electron Beam Melting-Manufactured Ti6Al4V

Electron beam melting (EBM) is one of the powder bed fusion technologies, which utilizes a high-energy electron beam, as a moving heat source, in order to melt (by rapid self-cooling) metal powder and produce parts in a layer-building fashion. Anyway, many technical aspects concerning the quality of EBM-produced components are still industrial open items and studies need to be carried out. In accordance with the industrial needs, in this work researchers have studied the influence of two process parameters, i.e., samples orientation and height in the build chamber. The experiments have consisted in rectangular parallelepiped (50 x 10 x 10 mm) samples Ti6Al4V produced by EBM following a two-factor DOE. A tomographic investigation of all the samples produced by EBM has been carried out in order to get a complete set of data on porosity defects that have been analyzed showing the influence of process parameters on the porosity generation and pointing out typical features of defect distributions. The results obtained from this work have given precious information to designers and EBM technologists in order to: optimize the components' design and the building setup obtaining a manufacturing process with the minimal level of porosity defects (best growth orientation). provide information for mechanical post-processing (metal removal).