Measurement of the Porosity of Additive-Manufactured Al-Cu Alloy Using X-Ray Computed Tomography

Abstract:

The additive manufacturing of metallic parts by means of selective laser melting is an emerging technology, the development of which is currently of great interest. The quality of the parts produced is evaluated mainly in terms of their mechanical properties, dimensional accuracy, and the homogeneity of the material. Because it is virtually impossible to produce parts without any internal porosity using powder-based additive manufacturing processes, measuring the porosity is critically important to optimizing the processing parameters. X-ray computed tomography is currently the only way used to measure the distribution of pores non-destructively and it can also measure the density and dimensional accuracy. Many studies have presented results of porosity measurements made using CT, but no standard methodology for the making of measurements and processing of data currently exists. The choice of parameters used for measurement and processing can have a significant impact on the results. This study focuses on the effect of voxel resolution on the resulting porosity number and discusses the possibilities for determining the threshold value for detecting pores. All the results presented in this study were obtained by analyzing the sample produced by selective laser melting technology from AlCu2Mg1.5Ni alloy.

• Periodical: Solid State Phenomena (Volume 258)
• Pages: 448-451
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.258.448
• Online since: December 2016
• Authors: Aneta Zatočilová, Tomáš Zikmund, Jozef Kaiser, David Paloušek, Daniel Koutný
• Keywords: Al-Cu Alloy, Porosity, Selective Laser Melting, Voxel Resolution, X-Ray Computed Tomography

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