Thermoplastic composites melt at higher temperatures and solidify when cooled down. This allows for repeated heating cycles and welding of components. A unique feature of thermoplastics composites.
Combined with their lightweight properties, toughness, fast curing cycles and ability to be recycled, these materials enable de-carbonization of aviation by producing lower emission aerostructures at an extended lifespan.
KVE has developed a patented induction welding process to assemble thermoplastic composites branded as KVE INDUCT®. We bring this technology to the market for high volume manufacturing of thermoplastic composite structures.
KVE INDUCT® is an assembly concept based on induction welding, where eddy currents are induced in carbon fiber reinforced laminates, resulting in a heat generation which melts the polymer and creates strong joints. KVE has patented the process in 2005.
Welding is performed in a rigid moulded set-up where the composite laminates are fixated in position. A welding coil moves over the assembly to melt the polymer at the desired location. Temperatures in the welding zone are controlled by a proprietary cooling mechanism, referred as heatsink.
The process enables seamless joining without rivets, fasteners or susceptor materials. Furthermore, the technology allows for new structural design concept and manufacturing methods. Applications have shown to provide a 20 % cost reduction and 10 % weight reduction relative to their thermoset counterparts.
Our concept allows the welding of closed box structures with variation in thickness, curvature and has principally no limited for component size.
The welding technology has been industrialized under KVE license in various aerospace applications by our customers. The flying and qualified examples show the potential of the welding process for optimized design with maximum performance.
Daher and KVE are developing an induction welded thermoplastic torsion box demonstrator. Daher designed a representative section demo of the horizontal tail plane (HTP) of Daher’s TBM aircraft which consisted of 5 components produced out of UD carbon fibre LM-PAEK thermoplastic tapes.
The demonstrator has been used to developed a certification approach according to the aerospace standards and thereby forms a key step towards welded UD based composite assemblies for aerospace applications.
The next step is to manufacture a fullscale version of the HTP, which will be presented in 2024.
Zero touch demo
Thermoplastics hold the prospect of fully automated part manufacturing. The concept has been showcased by KVE in the Zero touch labor project, executed for our customer Boeing. We developed a thermoplastic access panel concept where KVE INDUCT® has been implemented to assemble the panel.
In a lights off factory, the panels can be produced at lower cost and at higher rates compared to its thermoset counterpart.
KVE offers 2 standardized welding cells: A robotic cell and a mobile induction welding cell
For customers who are interested in exploring the welding technology or require support and consultancy, KVE offers the following services:
KVE can develop a turn key welding cell for the assembly of your thermoplastic composite structures. This service will include part dedicated weld tooling and full determination of the process parameters, thereby de-risking and advancing the development cycle for our customers.
In service equipment has components prone to wear due to the high temperatures of the welding process. KVE offers a series of standard spare parts. On request, dedicated replacement tooling can be supplied and KVE can be consulted for support.