Hybrid Manufacturing for Smart Composites Tooling - Manufacturing the future, Materials Engineering - Composites

Lead Research Organisation: University of Warwick
Department Name: Sch of Engineering

Abstract

The aim of the proposed project is to develop a robust hybrid manufacturing process for the production of smart tooling to be used in the manufacture of carbon fibre reinforced polymer (CFRP) composite parts. The project will hybridise additive manufacturing (3D printing), printed electronics and pick and place technologies in a single unattended manufacturing process for the production of composites tools. The project will be undertaken in collaboration with Neotech AMT (http://www.neotech-amt.com) based in Germany, who are a leading supplier of printed electronics systems. The ability to create smart tooling via the embedding of internet-enabled in-process monitoring sensor architectures in key locations of the tool will enable data driven real-time decision-making for composites manufacture as well as improved part traceability, intelligent predictive maintenance of tools and tool life management.[1] All are key aspects in the adoption of so-called Industry 4.0 and Smart Factories.[2-4]

At present, CFRP composite parts require expensive metallic tools (moulds) to be produced via conventional manufacturing processes such as CNC machining.[5] Material wastage, cost and lead-time mean that such tools are not cost effective for small volume or legacy production runs. For small volume production runs, cheaper epoxy or polymer composite tools are thus used.[6] Additive Manufacturing offers the possibility to produce cheaper polymer and polymer composite tools via a less labour intensive process but crucially with the added advantage of being able to incorporate features such as embedded sensors. If this were to be achieved today, it would require manual intervention or the use of multiple manufacturing systems, having a negative impact on aspects such as lead-time.

If a single process could be created that allowed for production of a robust polymer composite tool but with electronics and sensors embedded inside a tool for monitoring of process parameters during manufacture, the impact could be potentially vast. The UK composites industry alone has the opportunity to grow its current £2.3bn composite product market to £12.bn by 2030.[7] The technical barriers to development of this technology are in the capability of current manufacturing equipment, the limited materials science that has been done and finally the lack of robust models, simulation and design software that would allow subsequent parts to be manufactured effectively. The project will seek to address each of these technical barriers as objectives.

The impact from the project will be delivered via academic publications and through development of the technology with Neotech in order to deliver a joint commercial offering.

Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/N509796/1 01/10/2016 30/09/2021
1899881 Studentship EP/N509796/1 02/10/2017 30/09/2021 Elliott Griffiths
 
Description Carbon Fibre Reinforced Polymer (CFRP) is a composite material used in many industries such as aerospace and automotive for its high specific strength. The CFRP manufacturing process involves forming of the raw Carbon Fibre (CF) fabric onto a mould tool as part of a open or closed mould process - requiring a single side mould enclosed in a vacuum bag or two sides of a mould to enclose the CF respectively. Epoxy is then drawn through the CF stack and allowed to cure to form the final CFRP component.

There is a degree of uncertainty over the cure point of the CFRP component. If removed too early, the component may deform and a reduction in mechanical strength may be observed. It is therefore necessary to develop cure monitoring methods to observe the epoxy cure process. Current technologies require a closed mould tool (Resin Transfer Moulding) to align two parallel plates, or manual insertion of interdigital sensors onto the mould tool surface or into the composite laminate. Combining conductive composite thermoplastic with multi-material fused deposition modelling allows these sensor structures to be directly printed into the tool during manufacture, avoiding the subsequent assembly steps by integration to the process - forming a smart tool.

The published article "Multi-material fused deposition modelling for integration of interdigital dielectric sensors into carbon fibre composite tooling for in process cure monitoring" published in Sensors and Actuators A, details the use of multi-material 3D printing to manufacture dielectric sensors directly into mould tools use to produce carbon fibre reinforced polymer. Dielectric analysis allows for the curing process of the epoxy matrix to be monitored, ensuring the composite part is ready to be de-moulded.

To our knowledge, this is the first published study on the on the production of a mould tool and accompanying sensors for in process cure monitoring via a multi-material fused deposition modelling manufacturing process.
Exploitation Route 3D printing was chosen for the above study as it is a low cost, accessible technology. Therefore the above findings could be used by any party interested in monitoring the curing process during the manufacturing of Carbon Fibre Reinforce Polymer.
Sectors Aerospace, Defence and Marine,Chemicals,Digital/Communication/Information Technologies (including Software),Education,Electronics,Manufacturing, including Industrial Biotechology