Residual Stresses Analysis in AISI 316L Processed by Selective Laser Melting (SLM) Treated by Mechanical Post-Processing Treatments

Residual Stresses Analysis in AISI 316L Processed by Selective Laser Melting (SLM) Treated by Mechanical Post-Processing Treatments

Q. Portella, M. Chemkhi, D. Retraint

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Abstract. Selective Laser Melting (SLM) is a metal additive manufacturing process widely used in industry for its extraordinary versatility and minimal waste of material. Mechanical properties of SLM parts strongly depend on the process parameters such as power, scanning speed, hatch space and scanning strategy. Depending on these latter parameters, the SLM parts can be porous or fully dense. However, the high thermal gradients which are characteristic of this process induce complex distributions of residual stresses and defects such as micro-cracks. In the case where these internal stresses have a negative effect on the physical and mechanical integrity of SLM parts, the well-known solution proposed to reduce them is a post-heat treatment. Incidentally, superficial compressive residual stresses can also be generated by mechanical treatments and can improve the fatigue performance of the treated parts. The aim of this work is to examine the effect of Surface Mechanical Attrition Treatment (SMAT) on the residual stresses present in AISI 316L parts processed by SLM. The X-ray diffraction (XRD) results show that this mechanical treatment is a promising method to avoid the negative effect of tensile residual stresses resulting from the SLM process and can introduce a beneficial superficial compressive residual stress state. Moreover, work hardening and surface roughness were evaluated in all the untreated and SMATed samples.

Keywords
Residual Stresses, 316L, Selective Laser Melting, SMAT, Roughness, Micro-Hardness

Published online 9/11/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Q. Portella, M. Chemkhi, D. Retraint, ‘Residual Stresses Analysis in AISI 316L Processed by Selective Laser Melting (SLM) Treated by Mechanical Post-Processing Treatments’, Materials Research Proceedings, Vol. 6, pp 271-276, 2018

DOI: http://dx.doi.org/10.21741/9781945291890-43

The article was published as article 43 of the book Residual Stresses 2018

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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