What Potting Adhesive for UAV On-Board Auxiliary Control Boards? Selection Solution for PUR 1618 Low-Hardness Polyurethane Gel
ELAPLUS PUR 1618 A/B two-component low-hardness polyurethane gel is recommended as the primary candidate for potting of UAV on-board auxiliary control boards. Featuring low viscosity, post-cure flexibility and electrical insulation, it suits electronic control assemblies requiring local environmental protection and elastic cushioning. For auxiliary power supplies or control modules with higher structural support requirements, PUR 1661 A/B may be compared, while potting weight gain, actual temperature rise and equipment maintenance requirements must be assessed simultaneously. Low-altitude UAVs commonly integrate flight control systems, auxiliary power supplies, communication interfaces, status monitoring and other electronic modules. Electronic assemblies differ in mounting position, heat generation and protection requirements, so uniform potting material selection criteria are not applicable. For auxiliary control boards requiring protection, potting serves as part of the insulation, moisture-proofing and mechanical buffering design. Since UAVs are highly sensitive to weight, heat dissipation and maintenance clearance, define the actual protection scope first instead of fully filling the entire PCB by default. 1. Why Elastic Potting Is Required for UAV Auxiliary Control Boards During take-off, landing and normal flight, on-board electronics are subjected to vibration, temperature fluctuation and other environmental loads. For auxiliary control modules installed inside the airframe, properly selected potting adhesive covers designated circuits and provides mechanical protection for selected components and connection points. Unlike stationary industrial equipment, UAVs are sensitive to assembly weight. Additional mass introduced by potting compound is directly added to the airborne system. Therefore, material density, fill volume and structural protection performance shall all be considered in material selection. Furthermore, on-board electronic assemblies include components and connectors of varied sizes, and the mechanical properties of cured adhesive must match the actual structure. Low-hardness potting systems are preferred for PCBs that need to retain compliance. Note that precision inertial sensors, barometric sensors and other mechanically stress-sensitive devices may have…
