CHARGED Virtual Conference Webinar Explores How Gap Fillers Can Stress PCB Assemblies — and How to Avoid It

March 10, 2025 — Fujipoly presented a technical webinar at the CHARGED EVs Virtual Conference titled “Mitigating Stress in PCB Assemblies: Understanding Thermal Gap Filler Compression and PCB Deflection”, led by Applications Engineer Daniel Rosero. “Thermal gap fillers are essential for managing heat, but if not applied correctly, they can create mechanical stresses that compromise reliability. The key is balancing thermal performance with structural integrity.” — Daniel Rosero, Applications Engineer

As electronics designs become more compact and thermal management more critical, the use of thermal gap fillers is increasing — but so is the risk of inducing undesirable mechanical stress in Printed Circuit Boards (PCBs). The webinar unpacked the trade-offs and practical strategies engineers need to manage.

Key topics covered:

• Types of gap fillers — The difference between dispensable, putty, and viscoelastic gap fillers, and how their material properties influence stress and performance in different operating conditions.

• Compression characteristics — How filler thickness, compression rate, and filler type affect the load transmitted to the PCB and connected components.

• PCB deflection — How boards respond under stress: how much they bend or flex given different support strategies and where support is placed relative to the gap filler.

• Stress mitigation techniques — Practical design and engineering recommendations, including choosing the right filler, optimizing the layout of supports, and balancing thermal vs. mechanical requirements.

Attendees gained tools to better predict and control mechanical behavior in their assemblies, with the goal of improving reliability without sacrificing thermal performance. The session is now available on-demand, including a recording and slide deck.

Watch on Demand