Autoclave manufacturing is regarded as a benchmark for manufacturing aerospace quality composite parts. However, high accruing and operational costs limit their practicality for smaller-scale companies and are a barrier to production rates. In this project, a multi-zone, self-heating composite tool is developed to manufacture complex, high-quality, out-of-autoclave, lower wing stiffened composite panel.
The demand for thermoset composite parts is growing as more industries are using composites in their production lines due to improved properties. As the demand for composites increases in number, size and complexity, the need for improved manufacturing techniques is vital. One of the benchmark manufacturing techniques used is that of autoclave curing which, when applied in the manufacture of thermoset composite parts, ensures high-quality composite components. Nevertheless, it requires high costs for acquisition, operation, and tooling. Additionally, large autoclaves must sometimes be used inefficiently for small parts, which consumes excess energy. As a result, the use of autoclaves is not sustainable and limits the possibilities to expand composites growth.
Aim and Objectives
To speed up manufacturing time, and reduce costs without sacrificing quality, the industry is keen to develop and use out-of-autoclave processes. Thus, the COMBUSS project aims to build a tooling system that will incorporate self-heating capability with multiple heating zones, and advanced thermal management to manufacture business jet, lower wing stiffened panel.
Key objectives of this project are:
1- Designing a tool configuration compatible with the desired part
2- Identifying an efficient and safe heating method and integration strategy
3- Balancing product quality and energy consumption by developing a thermal management system that controls heated zones individually.
The business jet, lower wing stiffened panels are manufactured using Carbon Fibre Reinforced Polymer (CFRP). Hence, the tool is manufactured using CFRP to minimise the effect of thermal properties difference, providing a durable tool that can support and withstand many heating cycles. Since the tool is intended for production line use, it is necessary for the heating elements to be well-distributed, fully integrated with the tool material, and safe to operate and maintain.
To satisfy these requirements, a heating fabric is used to generate the required heat in multi-zones of the part and distribute it evenly with proximity to the tool and part surfaces.
In addition, its thin and light laminate shape enables a high level of mechanical bonding with the tool. A thermal management system is developed to efficiently control the thermal cure of the resin, with the capability of controlling and receiving feedback of, and from, each heated zone using a Graphical User Interface (GUI), temperature data acquisition system and Proportional Integral Derivative (PID) controllers.
A multi-zone self-heating composite manufacturing tool is developed to manufacture high quality, stiffened lower wing panels parts while reducing cost and energy consumption compared with autoclave processes. The heating elements are embedded within a robust tool while being controlled by a thermal management system.
This case study is part of COMBUSS project, which has received funding from the Clean Sky 2 Joint Undertaking under the European Union's Horizon 2020 research and innovation program under grant agreement No 821297.
Meet the Principal Investigator(s) for the project
Dr Mihalis Kazilas
- R&D programmes Director in the field of polymers characterisation and polymer composites manufacturing and joining processes. Creative thinker who enjoys problem solving and able to work with different stakeholders to achieve the optimum results in both technical and managerial environments.