3D Residual Stresses in Selective Laser Melted Hastelloy X

3D Residual Stresses in Selective Laser Melted Hastelloy X

J. Saarimäki, M. Lundberg, J.J. Moverare, H. Brodin

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Abstract. 3D residual stresses in as manufactured EOS NickelAlloy HX, produced by laser powder bed additive manufacturing, are analysed on the surface closest to the build-plate. Due to the severe thermal gradient produced during the melting and solidification process, profound amounts of thermal strains are generated. Which can result in unwanted geometrical distortion and effect the mechanical properties of the manufactured component. Measurements were performed using a four-circle goniometer Seifert X-ray machine, equipped with a linear sensitive detector and a Cr-tube. Evaluation of the residual stresses was conducted using sin2Ψ method of the Ni {220} diffraction peak, together with material removal technique to obtain in-depth profiles. An analysis of the material is reported. The analysis reveals unwanted residual stresses, and a complicated non-uniform grain structure containing large grains with multiple low angle grain boundaries together with nano-sized grains. Grains are to a large extent, not equiaxed, but rather elongated.

Keywords
Triaxial Stress, SLM, HX

Published online 12/22/2016, 6 pages
Copyright © 2016 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: J. Saarimäki, M. Lundberg, J.J. Moverare, H. Brodin, ‘3D Residual Stresses in Selective Laser Melted Hastelloy X’, Materials Research Proceedings, Vol. 2, pp 73-78, 2017

DOI: http://dx.doi.org/10.21741/9781945291173-13

The article was published as article 13 of the book Residual Stresses 2016

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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