• Cole, Ivan
• Xavier, Matheus

Abstract

Metal additive manufacturing (AM), using titanium, aluminium and stainless steel, has found multiple applications over the last few years. It provides freedom of design, the ability to build complex features, high precision, environmental and social sustainability and the opportunity of remanufacturing. The drawbacks to AM include the lack of understanding of AM materials, quality assurance and repeatability. In this context, the presence of defects, such as porosity, highly affect the properties of the part and is influenced by numerous parameters. In order to detect such defects, destructive techniques (e.g. optical microscopy and SEM) and nondestructive techniques (e.g. computed tomography and ultrasound) can be employed. Computed tomography (CT) offers the advantage of pore quantification (size, shape and distribution) and dimensional metrology, providing information over the volume of the sample and reducing material waste. Particularly, synchrotron CT allows quantitative reconstruction with rapid acquisition and better resolution. In this research project, XTRACT and DCM, two softwares developed at CSIRO, are used to first reconstruct the original projections in the monochromatic multi-energy X-ray CT datasets acquired at the Australian Synchrotron IMBL Beamline and then evaluate the material composition in three dimensions. DCM inputs the information from these CT datasets and gives the user the ability to distinguish multiple compositions inside a voxel, therefore acquiring information below CT resolution. Initial investigations on a 316L stainless steel sample demonstrated the potential of using these softwares to evaluate inclusions present in the part. We thank Christophe Comte and Neil Wilson at Romar Engineering for the sample preparation.

Topics

• impedance spectroscopy
• pore
• stainless steel
• inclusion
• scanning electron microscopy
• tomography
• aluminium
• titanium
• porosity
• optical microscopy
• additive manufacturing