Optimisation of single contour strategy in selective laser melting of Ti-6Al-4V lattices
ISSN: 1355-2546
Article publication date: 24 February 2022
Issue publication date: 5 May 2022
Abstract
Purpose
Selective laser melting (SLM) is increasingly used to manufacture bone implants from titanium alloys with particular interest in porous lattice structures. These complex constructs have been shown to be capable of matching native bone mechanical behaviour leading to improved osseointegration while providing numerous clinical advantages, encouraging their broad use in medical devices. However, producing lattices with a strut diameter similar in scale to a typical SLM melt pool or using the same process parameters and scan strategies intended for bulk solid components may lead to geometric inaccuracies. The purpose of this study is to evaluate and optimise the single contour strategy for the production of Ti-6Al-4V lattices.
Design/methodology/approach
Herein, the potential of an unfilled single contour (SC) scanning strategy to improve the reproducibility of porous lattices when compared with a single contour and fill approach (SC + F) is explored. For this purpose, two parametric analysis were carried out on Ti-6Al-4V diamond unit cell lattices with different strut sizes and scan strategies. Porosity and accuracy measurements were correlated with processing parameters and printing strategy to provide the optimal processing window for lattice manufacturing.
Findings
SC is shown to be a viable strategy for production of Ti-6Al-4V lattices with a strut diameter below 350 µm. Parametric analysis highlights the limits of this method in producing fully dense struts with energy density presented as a useful practical tool to guide some aspects of parameter selection (design strut diameter achieved at approximately 0.1 J/mm in this study). Finally, a process map combining data from both parametric studies is provided to guide, predict and control lattice strut geometry and porosity obtained using the SC strategy.
Originality/value
These results explore the use of non-standard SC scanning strategy as a viable method for producing strut-based lattice structures and compare against the traditional contour and fill approach (SC + F).
Keywords
Acknowledgements
This work was supported by the EPSRC funded project: Process Design to Prevent Prosthetic Infections (EP/P02341X/1).
The authors declare no conflict of interest.
Citation
Cao, X., Carter, L.N., Villapún, V.M., Cantaboni, F., De Sio, G., Lowther, M., Louth, S.E.T., Grover, L., Ginestra, P. and Cox, S.C. (2022), "Optimisation of single contour strategy in selective laser melting of Ti-6Al-4V lattices", Rapid Prototyping Journal, Vol. 28 No. 5, pp. 907-915. https://doi.org/10.1108/RPJ-04-2021-0103
Publisher
:Emerald Publishing Limited
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