During the project, the main results achieved were as follows:
WP1 Performance specifications
- Concentrated on medium-performance, continuous fibre reinforced materials, aiming for properties similar to conventional manufacturing.
- Conducted a comprehensive review of conventional and additive manufacturing processes, highlighting the need for improved 5-axis control in additive manufacturing.
- Developed specific KPIs for the DiCoMI process, covering aspects like target applications, materials, system architecture, extruder requirements, and financial considerations.
WP2 Composite materials studies:
- Conducted an extensive review to select a range of existing composite materials, narrowing it down to 11 potential fibres for reinforcement and 7 polymer matrix materials suitable for the DiCoMI system.
- Investigated new polymer/fibre combinations, emphasizing the need for surface treatment of fibres before adding them to the polymer matrix and identifying natural fibres like jute, sisal, and hemp as promising for future development.
- Performed material extrusion tests with various polymer and composite materials, including PLA with carbon fibre reinforcement and a bio-sourced PLA with wood fibre reinforcement, concluding that any material available in filament form could meet the manufacturability requirements of the DiCoMI system.
- Identified carbon fibre (CF) reinforced PLA, PA, and ABS, along with wood fibre reinforced Ingeo PLA as final target materials, although CF-reinforced PEEK emerged as a common choice in aerospace and other industries.
- Tested material specimens made from various composites under tensile and compression conditions, finding that all specimens showed improved mechanical properties compared to pure polymers, especially for CFR polyamide/carbon fibre materials.
WP3 Design of hybrid manufacturing system
- Determined key parameters for additive processing of target materials, including a maximum extrusion temperature of 400°C, platform temperature of 170°C, chamber temperature of 120°C, and nozzle tip diameter ranging from 0.4 to 0.9 mm.
- Identified essential parameters for subtractive processing, including the use of Guhring CR100 dry milling cutters, a spindle speed of 5000 rpm, and a cutter feed rate of 60 mm/s.
- Developed a twin-tool system architecture (extrusion head plus milling cutter) with automated change-over between tools, a single machine configuration, and non-continuous deposition with integrated mechanical cutting of continuous reinforcement fibres.
- Completed the detailed design of the hybrid manufacturing system, which included a new extrusion head design, integration of a rotary table, and exploration of a cost-effective tool changer.
- Demonstrated the system's capability for material extrusion with a range of continuous fibres, surpassing commercial systems in using PLA, PETG, and nylon polymers for continuous fibre fabrication and processing new materials like biodegradable yarns and metallic fibres.
WP4 Prototyping and demonstration
- Successfully designed, prototyped, and tested the DiCoMI system, focusing on modular design, technical problem-solving, and quality assurance.
- Developed a slicer software using Marlin-based G-code libraries for the MAMEX system, featuring a user-friendly interface for direct input of parameterised CAD parts and machine code generation. The software accommodates continuous strand fibres and has been upgraded to include a rotational print bed.
- Created guidelines for the DiCoMI Material Extrusion (ME) system, which allows 3D layer building with no fixed orientation. The system offers new possibilities in design and material deposition, including controlling extrusion tracks in three dimensions and optimising part strength and stiffness.
- Achieved multi-axis Additive Manufacturing (AM) and fibre deposition through two methods: coating fibres with AM polymers and a dual feed custom AM print head.
- Conducted tests on parts fabricated with continuous fibres, revealing differences in print time and cost among methods. Polymer melt extrusion was the fastest and cheapest, while dual feed fibre and filament were slower and more expensive.
WP5 Project Co-ordination, Management and Dissemination
- Two presentations about the project's results made at MTeM 2023, Cluj-Napoca, Romania.
- Project video published:
https://www.youtube.com/watch?v=4Y_l6nmVFyA(si apre in una nuova finestra)- 9 collaborative proposals prepared related to DiCoMI. 5 funded.
