To read this content please select one of the options below:

Deformations and stresses prediction of cantilever structures fabricated by selective laser melting process

Lan Li (Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri, USA)
Tan Pan (Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri, USA)
Xinchang Zhang (Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri, USA)
Yitao Chen (Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri, USA)
Wenyuan Cui (Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri, USA)
Lei Yan (Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri, USA)
Frank Liou (Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri, USA)

Rapid Prototyping Journal

ISSN: 1355-2546

Article publication date: 15 February 2021

Issue publication date: 2 April 2021

432

Abstract

Purpose

During the powder bed fusion process, thermal distortion is one big problem owing to the thermal stress caused by the high cooling rate and temperature gradient. For the purpose of avoiding distortion caused by internal residual stresses, support structures are used in most selective laser melting (SLM) process especially for cantilever beams because they can assist the heat dissipation. Support structures can also help to hold the work piece in its place and reduce volume of the printing materials. The mitigation of high thermal gradients during the manufacturing process helps to reduce thermal distortion and thus alleviate cracking, curling, delamination and shrinkage. Therefore, this paper aims to study the displacement and residual stress evolution of SLMed parts.

Design/methodology/approach

The objective of this study was to examine and compare the distortion and residual stress properties of two cantilever structures, using both numerical and experimental methods. The part-scale finite element analysis modeling technique was applied to numerically analyze the overhang distortions, using the layer-by-layer model for predicting a part scale model. The validation experiments of these two samples were built in a SLM platform. Then average displacement of the four tip corners and residual stress on top surface of cantilever beams were tested to validate the model.

Findings

The validation experiments results of average displacement of the four tip corners and residual stress on top surface of cantilever beams were tested to validate the model. It was found that they matched well with each other. From displacement and residual stress standpoint, by introducing two different support structure, two samples with the same cantilever beam can be successfully printed. In terms of reducing wasted support materials, print time and high surface quality, sample with less support will need less post-processing and waste energy.

Originality/value

Numerical modeling in this work can be a very useful tool to parametrically study the feasibility of support structures of SLM parts in terms of residual stresses and deformations. It has the capability for fast prediction in the SLMed parts.

Keywords

Acknowledgements

This project was supported by National Science Foundation Grant CMMI 1625736, the Intelligent Systems Center and Material Research Center at Missouri S&T, Navair, Product Innovation and Engineering. Their financial support is greatly appreciated.

Citation

Li, L., Pan, T., Zhang, X., Chen, Y., Cui, W., Yan, L. and Liou, F. (2021), "Deformations and stresses prediction of cantilever structures fabricated by selective laser melting process", Rapid Prototyping Journal, Vol. 27 No. 3, pp. 453-464. https://doi.org/10.1108/RPJ-10-2019-0273

Publisher

:

Emerald Publishing Limited

Copyright © 2021, Emerald Publishing Limited

Related articles