Selective laser melting of thermal pre-treated metal oxide doped aluminum oxide granules
Stefan Pfeiffer,
Malgorzata Makowska,
Kevin Florio,
Dario Ferreira Sanchez,
Federica Marone,
Xiaoyan Zhang,
Christos G. Aneziris,
Helena Van Swygenhoven,
Konrad Wegener,
Thomas Graule
Affiliations
Stefan Pfeiffer
Laboratory for High Performance Ceramics, Empa – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600, Dübendorf, Switzerland; Institute of Ceramic, Glass and Construction Materials, TU Bergakademie Freiberg, Agricolastraße 17, 09599, Freiberg, Germany; Corresponding author. Laboratory for High Performance Ceramics, Empa – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600, Dübendorf, Switzerland.
Malgorzata Makowska
Photon Science Division, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
Kevin Florio
Institute of Machine Tools and Manufacturing, ETH Zürich, Leonhardstrasse 21, 8092, Zurich, Switzerland
Dario Ferreira Sanchez
Photon Science Division, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
Federica Marone
Photon Science Division, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
Xiaoyan Zhang
Laboratory for High Performance Ceramics, Empa – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600, Dübendorf, Switzerland
Christos G. Aneziris
Institute of Ceramic, Glass and Construction Materials, TU Bergakademie Freiberg, Agricolastraße 17, 09599, Freiberg, Germany
Helena Van Swygenhoven
Photon Science Division, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
Konrad Wegener
Institute of Machine Tools and Manufacturing, ETH Zürich, Leonhardstrasse 21, 8092, Zurich, Switzerland
Thomas Graule
Laboratory for High Performance Ceramics, Empa – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600, Dübendorf, Switzerland; Institute of Ceramic, Glass and Construction Materials, TU Bergakademie Freiberg, Agricolastraße 17, 09599, Freiberg, Germany
The influence of powder bed density on the final density and microstructure of aluminum oxide parts manufactured by direct selective laser melting has been studied. Iron oxide and manganese oxide nanoparticles were used to improve laser absorption by over eighty percent. To achieve such values, flowable doped alumina granules were prepared by spray drying. Thermal treatment of the granules at 1600 °C and consecutive mixing with coarse alumina allowed improvement of the tapped powder densities, reaching a maximum value of 56.4% of the theoretical density. This led to laser processed parts with densities up to 98.6% measured by tomographic microscopy. Measurements with an integrating sphere and an UV-VIS-NIR spectrophotometer employing Kubelka-Munk theory show the decrease of absorptance caused by thermal pre-treatment. 3D mapping by X-ray μ-beam fluorescence contrast tomography and high resolution synchrotron powder diffraction provide information about the variation of dopant distribution and composition within the granules.
