Effective thermal management is vital for high-power PCBAs to prevent overheating and ensure long-term reliability. Thermal Interface Materials (TIMs) bridge gaps between heat sources (e.g., CPUs, GPUs) and heat sinks. Thermal greases, with fillers like silver or alumina, offer high thermal conductivity (1–10 W/m·K) but require reapplication due to pump-out effects. Phase-Change Materials (PCMs) solidify at room temperature and melt during operation, providing stable thermal performance without drying. For rigid applications, thermal pads (2–8 W/m·K) offer uniform pressure and vibration resistance, making them ideal for automotive electronics.

Advanced solutions include Metal-Core PCBs (MCPCBs), which use aluminum or copper substrates to spread heat efficiently. Embedded copper coins enhance local cooling for high-power components, while vapor chambers (10x more effective than heat pipes) distribute heat uniformly across large areas. Graphite sheets, with planar conductivity up to 1,500 W/m·K, are used in 5G base stations to manage 200W+ power dissipation. Liquid cooling loops with dielectric fluids are employed in data centers for sub-ambient cooling.

Design strategies play a crucial role. Optimizing component placement to avoid hotspots, adding thermal vias to conduct heat to inner layers, and using thermal planes reduce junction temperatures by 10–20°C. Computational Fluid Dynamics (CFD) simulations predict airflow and heat distribution, guiding layout decisions. Sustainability trends favor biodegradable TIMs and recycled metals, aligning with eco-friendly manufacturing. By integrating these materials and techniques, manufacturers achieve thermal resistance values below 0.1°C/W, ensuring device reliability in harsh environments.