Comparison of Multi-Pass Laser Cutting with Other Cutting Processes for Fibre Reinforced Polymer Composites
By Tony Pramanik and Ian Jones
Laser cutting has significant potential as a method of cutting fibre-reinforced polymer composites (FRPs), given that it is a non-contact, precise, low heat input, high-productivity, highly automated process. Currently, however, laser cutting of FRPs is not fully optimised and is not commonly used by industry. This report presents results of trials to develop and demonstrate multi-pass laser cutting and benchmark it against the competing processes of milling and water-jet machining. A detailed assessment of the cut edge quality and performance for all cutting methods is also provided.
- Multi-pass laser cutting procedures using a pulsed fibre laser source were developed for two carbon fibre reinforced materials: a thermoset epoxy (RP507) and a thermoplastic nylon (PA12).
- The main defects visible in the cut specimens were as follows:
● Milled: Splintering of the top layers from some of the samples.
● Water-jet: Delamination of numerous layers and rounding of edges.
● Multi-pass laser: Loose fibres and discoloration in the heat-affected zones.
- Plain pin bearing test results were highest for milled samples and lowest for laser cut samples.
- The open hole tension test results for the two materials were as follows:
● For RP507: Similar for all three processes.
● For PA12: Highest for water-jet machined specimens, with multi-pass laser cut and milled specimens both giving a similar, lower failure load.
Cross-section of of pulsed multi-pass laser cut carbon fibre/RP507 composites
Cross-section of of water-jet cut carbon fibre/RP507 composite