ESENSE: Tooling enabling temperature homogeneity and embedded graphene sensors

The growing demand for composite materials in aerospace due to lightweight advantages over their metallic counterparts has given a new impetus to the development of eco-friendly, cost-effective composite manufacturing processes. A350 XWB and Boeing 777X use more than 50% composites by weight, with the latter having the world's largest aircraft wings formed from composite materials.

Historically, aerospace composites have been manufactured using autoclave processes. Although autoclaves comprise the benchmark manufacturing technique that ensures high-quality composite components, their high costs for acquisition and operation, long production time and inflexible manufacturing pose serious challenges to the aerospace industry.

ESENSE aims to bring to market a more versatile and less costly, self-heated Out-of-Autoclave (OOA) tooling solution with multiple heating zones and advanced thermal management in order to eliminate the need for costly and energy-intensive autoclaves. It will introduce and combine two complementary niche technologies, building on consortium partners' previous work in heating technologies and thermal control management, to optimise the heating efficiency of the tooling and achieve temperature homogeneity even in complex shapes targeting the manufacture of thermoset composite parts.

ESENSE objectives are:

1. Design of complex composite tooling with an integrated multi-zone self-heated system utilising Energy Carbon's composite heating fabric and HCS's graphene heated ink, achieving efficient localised heating and temperature homogeneity eliminating temperature variations.
2. Development and optimisation of the advanced graphene sensors embedded in the part, which are at least 5Χ more sensitive than conventional solutions. Two distinct formats will be used: the percolative sensor measuring temperature during the manufacturing process and strain during service and a capacitive sensor measuring resin conductivity during the manufacturing process facilitating cure monitoring.
3. Development of advanced in-situ monitoring and real-time data acquisition of actual material properties at specific critical locations, enabling quality signature of every part.

ESENSE's benefits are:

1. 45-55% less costly solution than traditional autoclaves.
2. First-time-right, high-quality and cost-effective OOA aerospace parts.
3. Unparalleled part quality assurance with real-time process monitoring and nonintrusive through-life sensing capabilities via embedded graphene ink sensors.
4. 20% shorter lead times and 15% energy savings throughout the composite curing processing cycle.

Project partners

• Atlas Composite Technologies (Lead)
• TWI Ltd
• Haydale Composite Solutions Ltd
• Brunel University London
• Advise-Deta Ltd
• Haydale Ltd
• Energy Carbon Ltd