Wevo Chemie introduces new thermally conductive silicone

Ostfildern-Kemnat, Germany – Whether it’s high-voltage batteries, power electronics or humanoid robotics – when developing modern technologies, compact installation spaces, weight targets, thermal management and cost-effective manufacturing processes need to be considered simultaneously. With WEVOSIL 26029 FL, WEVO-CHEMIE GmbH presents a new silicone gap filler specially designed to meet these demands. The material combines a thermal conductivity of 3 W/m·K with rheological properties optimised for processing and a comparatively low density of 2.22 g/cm³.

Conventional paste-like gap fillers with high viscosity quickly reach their limits when filling gaps measuring just a few millimetres. WEVOSIL 26029 FL, on the other hand, can be reliably applied, even in tight spaces.

With its precisely tailored rheological properties, Wevo’s new silicone gap filler can be applied as a bead and compressed into place using low pressure. If no free areas need to be connected, gaps can also be filled by injection – the product then remains in the gap without flowing out, owing to its high sag resistance.

The silicone gap filler can be processed using standard dosing systems, such as those used for potting applications – with both piston and eccentric screw pumps. Extruders or barrel as well as drum extrusion stations, which are required for many highly-filled gap fillers, are not necessary.

The sedimentation-optimised formulation of WEVOSIL 26029 FL allows it to be stirred using simple mixing tools within a few minutes, even after prolonged storage. The choice of filler and the low viscosity also help to prevent abrasion in the dosing systems and the associated maintenance costs.
Material properties for weight-optimised assemblies

Following curing without any by-products or volume shrinkage, the silicone gap filler provides tackiness (long-lasting surface stickiness) and good mechanical properties. As a thermal interface material (TIM), WEVOSIL 26029 FL combines a thermal conductivity of 3 W/m·K with a density of just 2.22 g/cm³. Featuring a significantly lower density than many highly-filled gap fillers with comparable thermal conductivity, the new Wevo product also supports weight-optimised assembly designs.

In addition to high-voltage batteries – such as those for electric vehicles or industrial environments – robotics is one of the potential areas of application for this material. In humanoid robots, for example, compact high-performance batteries or electronic components can be thermally bonded to the outer skin using the silicone gap filler, even in narrow areas with thin layers of 1 to 2 mm, to support rapid, uniform heat dissipation.