Numerical investigation on the effect of solder paste rheological behaviour and printing speed on stencil printing
Soldering & Surface Mount Technology
ISSN: 0954-0911
Article publication date: 1 July 2020
Issue publication date: 23 August 2020
Abstract
Purpose
The purpose of this paper is to investigate the effect of different viscosity models (Cross and Al-Ma’aiteh) and different printing speeds on the numerical results (e.g. pressure over stencil) of a numerical model regarding stencil printing.
Design/methodology/approach
A finite volume model was established for describing the printing process. Two types of viscosity models for non-Newtonian fluid properties were compared. The Cross model was fitted to the measurement results in the initial state of a lead-free solder paste, and the parameters of a Al-Ma’aiteh material model were fitted in the stabilised state of the same paste. Four different printing speeds were also investigated from 20 to 200 mm/s.
Findings
Noteworthy differences were found in the pressure between utilising the Cross model and the Al-Ma’aiteh viscosity model. The difference in pressure reached 33-34% for both printing speeds of 20 and 70 mm/s and reached 31% and 27% for the printing speed of 120 and 200 mm/s. The variation in the difference was explained by the increase in the rates of shear by increasing printing speeds.
Originality/value
Parameters of viscosity model should be determined for the stabilised state of the solder paste. Neglecting the thixotropic paste nature in the modelling of printing can cause a calculation error of even approximately 30%. By using the Al-Ma’aiteh viscosity model over the stabilised state of solder pastes can provide more accurate results in the modelling of printing, which is necessary for the effective optimisation of this process, and for eliminating soldering failures in highly integrated electronic devices.
Keywords
Acknowledgements
This paper was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences. Supported by the ÚNKP-19-4 New National Excellence Program of the Ministry for Innovation and Technology. The research reported in this paper was supported by the Higher Education Excellence Program of the Ministry of Human Capacities in the frame of Artificial Intelligence research area of Budapest University of Technology and Economics (BME FIKP-MI/SC).
Citation
Krammer, O., Al-Ma’aiteh, T.I., Illes, B., Bušek, D. and Dušek, K. (2020), "Numerical investigation on the effect of solder paste rheological behaviour and printing speed on stencil printing", Soldering & Surface Mount Technology, Vol. 32 No. 4, pp. 219-223. https://doi.org/10.1108/SSMT-11-2019-0037
Publisher
:Emerald Publishing Limited
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