Effect of steam autoclaving on laser sintered polyamide 12
ISSN: 1355-2546
Article publication date: 12 November 2020
Issue publication date: 8 January 2021
Abstract
Purpose
The use of laser sintering (LS) in the medical sector has increased dramatically in recent years. With the move towards direct use of these parts in clinical applications, there is a greater need to understand the effects of standard processes on the part properties. The purpose of this study is to determine the effect that steam sterilisation has on the mechanical properties of LS polyamide 12 parts.
Design/methodology/approach
The research presented here focusses on the effect of a single steam sterilisation cycle on the mechanical properties of polyamide 12 parts manufactured using LS. The influence of water content on the properties was investigated, with additional drying steps trialled to establish the potential to reverse any changes observed and to determine their root cause.
Findings
The results show that steam sterilisation has a significant effect on the mechanical properties of LS polyamide 12 parts, with a 39% reduction in elastic modulus, a 13% decrease in ultimate tensile strength and a 64% increase in the elongation at break. These properties were also all found to correlate with the water content, suggesting that this was the cause of the difference. The original properties of the parts were able to be recovered after oven drying.
Practical implications
These results show that with an additional drying step, LS polyamide 12 parts can be steam sterilised with no effect on the mechanical properties.
Originality/value
This is believed to be the first investigation into the effects of steam sterilisation in isolation on LS polyamide 12 parts, the first instance of drying parts to recover mechanical properties and the first instance of multiple water content measurements being directly linked to the mechanical properties.
Keywords
Acknowledgements
The authors would like to acknowledge Dr Cheryl Miller, primary supervisor of Maha Omran, for conceiving and initiating preliminary experimental trials in this area; and Dr Robert Turner for carrying out the steam sterilisation of the specimens. This work was funded by The University of Sheffield Department of Mechanical Engineering Centenary Scholarship and the EPSRC Doctoral Training Partnership. This work is aligned with the EPSRC Future Manufacturing Hub in Manufacture using Advanced Powder Processes (EP/P006566/1).
Citation
Wingham, J.R., Omran, M., Shepherd, J. and Majewski, C. (2021), "Effect of steam autoclaving on laser sintered polyamide 12", Rapid Prototyping Journal, Vol. 27 No. 1, pp. 45-52. https://doi.org/10.1108/RPJ-11-2019-0288
Publisher
:Emerald Publishing Limited
Copyright © 2020, Emerald Publishing Limited