Advancing Heat Sink Design Through DMLS

Advancing Heat Sink Design Through DMLS

Overview

As electronic components continue to increase in power density, the need for effective passive cooling systems becomes more critical. Natural convection — a quiet, low-cost, and low-interference cooling method — often struggles to meet the demands of medium to high power outputs. This case study explores how Direct Metal Laser Sintering (DMLS), an advanced additive manufacturing technology, was used to redesign a traditional extruded LED heat sink to significantly improve thermal performance.

Challenge

Traditional heat sinks are limited by their simple geometries, which are typically produced through extrusion, forging, or pressing. These methods restrict airflow optimization and surface area expansion — two key elements in improving heat dissipation. Plunkett Associates and partners set out to answer a critical question: Can a DMLS-manufactured heat sink, designed with advanced airflow-enhancing geometries, outperform a standard extruded heat sink under natural convection conditions?

Solution: Leveraging Additive Manufacturing

As part of the Technology Strategy Board-funded SAVINGs project, Plunkett Associates collaborated with Crucible Industrial Design, EOS, 3T RPD, and others to investigate how DMLS could enable new thermal management capabilities.

Using 3D CAD and CFD simulations, multiple heat sink geometries were developed specifically to take advantage of DMLS’s unique layer-by-layer build approach. This process allowed for:

• Complex, organic geometries unachievable with traditional methods
• Increased surface area and airflow channels
• Designs optimized for natural convection

Validation

The top five designs were produced in aluminum using DMLS by 3T RPD. Testing showed a consistent reduction in heat source temperature when compared to the traditional extruded benchmark. All five designs validated the CFD results with physical performance improvements.

Conclusion

This project demonstrated the transformative potential of DMLS in thermal management applications. With its ability to create fully dense, high-performance metal parts directly from CAD — and without the limitations of traditional manufacturing — DMLS offers a scalable, effective solution for the growing thermal demands of modern electronics. Key Takeaway: DMLS-enabled heat sinks achieved measurable improvements in passive cooling performance, offering a viable alternative to complex or expensive active cooling methods.