Optimisation of a novel hot air contactless single incremental point forming of polymers

Journal article

Almadani, M., Guner, A., Hassanin, H. and Essa, K. 2024. Optimisation of a novel hot air contactless single incremental point forming of polymers. Journal of Manufacturing Processes. 117, pp. 302-314. https://doi.org/10.1016/j.jmapro.2024.02.042
AuthorsAlmadani, M., Guner, A., Hassanin, H. and Essa, K.
Abstract

This study presents a new contactless sheet forming method that utilises hot air as a forming tool to address tool wear challenges in single-point incremental forming. Experiments were conducted on a 3-axis CNC machine equipped with a hot air nozzle on a polycarbonate sheet. A design of experiment (DOE) approach was employed, evaluating five control factors: air pressure, air temperature, feed rate, tool offset, and step down. The evaluation criteria for the formed sheets are profile variation, thickness variation, and surface roughness. The results indicate that air temperature and feed rate have the most significant influence on the deformation process. Additionally, air pressure and feed rate substantially impact both thickness variation and surface roughness of the formed material. To optimise the process parameters for high-quality forming, a prediction model is developed. The optimised process shows good agreement with the predicted model regarding profile and thickness variations. However, it does not align with surface roughness due to the stepwise nature and inherent waviness of the contactless forming technique. This study offers a promising approach for developing innovative contactless forming techniques using hot pressurised air as a forming tool. The proposed technique has the potential to significantly reduce tool wear and lubrication requirements.

KeywordsSheet forming ; Response surface methodology; Contactless incremental forming; Formability; Design of experiment
Year2024
JournalJournal of Manufacturing Processes
Journal citation117, pp. 302-314
PublisherElsevier
ISSN1526-6125
Digital Object Identifier (DOI)https://doi.org/10.1016/j.jmapro.2024.02.042
Official URLhttps://doi.org/10.1016/j.jmapro.2024.02.042
Publication dates
Print14 Mar 2024
Publication process dates
Accepted19 Feb 2024
Deposited28 Mar 2024
Publisher's version
File Access Level
Open
Output statusPublished
References

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