How LPBF is Simplifying Cold Plates and CDU Components for Better Data Center Cooling

A practical view on applications, materials, manufacturability, and production readiness for liquid cooling hardware

AI and high-performance computing are driving unprecedented thermal loads in data centers. Chip heat flux is now pushing beyond 100 W/cm², forcing the industry to rethink conventional air cooling and even traditional liquid-cooling hardware. [1]

Laser Powder Bed Fusion (LPBF) additive manufacturing is relevant because it can create monolithic internal flow paths, including microchannels ~0.25–1.0 mm and consolidate assemblies, reducing leak paths while enabling faster iteration from concept to qualified builds. [3]

Key Liquid Cooling Applications in Data Centers
1) Coolant Distribution Units (CDUs)

A Coolant Distribution Unit (CDU) is a centralized system used in liquid-cooled data centers to circulate and regulate coolant between facility water systems and IT equipment. It controls temperature, pressure, and flow rate while isolating the data-center loop from the building loop. Typical CDUs include pumps, heat exchangers, manifolds, and monitoring systems, making them critical infrastructure for scaling liquid cooling in high-density environments.

While a full rack-level CDU can be large (conventionally ~600 × 1000 × 2000 mm, 150–600 kg), several CDU subcomponents are strong candidates for LPBF where compactness and thermal/flow optimization matter:

• Compact heat exchangers with optimized internal passages

• Manifolds/flow distributors designed for uniform flow and lower pressure drop

2) Direct-to-Chip (D2C) cooling cold plates

Direct-to-Chip cooling delivers liquid coolant directly to cold plates mounted on high-heat components like CPUs and GPUs. By absorbing heat at the source, D2C improves thermal efficiency versus air cooling and supports higher compute density. [1]

Cold plates are compact but highly complex internally: CPU cold plates are often ~60 × 60 × 15 mm, GPU cold plates ~120 × 120 × 20 mm, and multi-chip/AI plates can reach ~200 × 200 × 20 mm. Performance comes from microchannel networks often in the 0.25–1 mm range, which must be designed for manufacturability and inspection.

Material Selection for Heat Transfer and Corrosion Resistance in Liquid Cooling 

Liquid cooling hardware must balance thermal conductivity, corrosion resistance, and compatibility with coolant chemistry (water, glycol mixtures, dielectric fluids, and in some systems refrigerants). Copper, aluminium, and stainless steel are common choices; copper offers very high conductivity (~390–400 W/m·K), while aluminium provides a strong conductivity-to-weight balance (~200–235 W/m·K).

For LPBF, the following options are particularly relevant for cold plates and CDU components:

• CuCrZr (LPBF): ~300–400 W/m·K  strong fit for D2C cold plates with microchannels

• AlSi10Mg (LPBF): ~120–180 W/m·K  suitable where weight and cost sensitivity are higher

• Aheadd CP1 (LPBF): ~160–200 W/m·K a balance of conductivity with high corrosion resistance

Understanding the importance of early validation in Design for AM (DfAM) and buildability

Considerations for DfAM in cooling components differ by scale. Cold plates are chip-level parts (often ~100 × 100 × 15 mm) but feature very high internal complexity (microchannels), typically produced as single-piece builds to maximize performance and reduce leak paths. CDU components are usually larger subsystem-level parts (up to ~300 × 300 × 200 mm) with high flow-and-thermal demands and may be segmented depending on the envelope and post-processing strategy.

In practice, production readiness comes down to validating a few non-negotiables early:

• Powder removal strategy for microchannels (a known LPBF challenge at 0.25–1 mm channel sizes)

• Leak integrity and flow validation as part of the standard manufacturing route

Where LPBF delivers a measurable advantage

The advantages of LPBF are most evident in performance, integration, and speed, especially for 3D printed liquid cold plates and selected CDU subcomponents.

Key advantages

• Higher heat transfer from optimized internal surfaces and flow paths (including microchannels)

• Conformal, application-specific channels matched to heat sources

• Monolithic construction that reduces joints and leak paths

• Part consolidation that reduces assembly steps and system complexity

• Flow optimization that can reduce pressure drop and pump demand at the system level

• Faster iteration from design to qualified pilot builds

Ensuring Qualification and Compliance While Validating the Invisible 

Liquid cooling hardware sits in a safety- and reliability-critical environment, so qualification cannot be an afterthought. Depending on the application, compliance requirements such as UL / IEC 62368-1 and customer-specific vendor qualification processes may apply. [2] For LPBF cold plates, the hardest questions are often about internal features because internal geometry is difficult to inspect with traditional methods.

A production-ready approach tackles common objections head-on:

• Internal geometry validation: combine leak testing with CT scanning to verify channels; start with high sampling and optimize as volume stabilizes.

• As-built finish: use finishing (e.g., AFM) and validate against pressure-drop and flow targets.

• Scaling: multi-laser and larger build volumes enable production scaling once the process is validated.

• Powder removal: mitigate clogging risk with DfAM, process validation, and test plans around critical channel features.

How Wipro 3D engages: from feasibility to qualified pilot batches

At Wipro 3D, our focus is not only prototyping we work toward production-grade LPBF parts for cold plates and CDU components with the controls OEMs expect: leak testing, validated internal geometries (including CT inspection and traceability where required), and repeatable builds in relevant materials such as CuCrZr, AlSi10Mg, and Aheadd CP1. As programs mature, we also plan for scale through throughput modeling aligned to multi-laser and larger build-volume platforms.

We typically engage through a short feasibility sprint and a pilot build, then scale with a validated process plan and inspection route (leak testing and internal-feature validation as required).

If you are an OEM, integrator, or end user building next-generation liquid cooling for AI infrastructure, the fastest path to value is to begin with a design or a thermal/flow performance target. We can then jointly determine whether LPBF is the right lever on cold plates, on CDU subcomponents, or both.

• Bring: a design, envelope constraints, coolant conditions, and target heat load/pressure drop

• We deliver: rapid manufacturability feedback (DfAM), a production feasibility and cost model, and a qualified pilot batch (typically 10–50 parts) with leak testing and internal-feature validation as required

As liquid cooling becomes a foundation for AI data centers, the winning solutions will be those that combine thermal performance with manufacturable, inspectable designs. LPBF is not a blanket replacement for conventional manufacturing, but for high-performance cold plates and the right CDU components, it can unlock architectures that move the needle on efficiency, density, and time-to-scale.

References

1. HDR. “Direct-To-Chip Liquid Cooling.” (Mar 24, 2023).
2. International Electrotechnical Commission (IEC). IEC 62368-1:2023 “Audio/video, information and communication technology equipment – Part 1: Safety requirements.” (Edition 4.0, May 26, 2023).
3. An, J., et al. “Pressure Capacity Assessment of L-PBF-Produced Microchannel Heat Exchangers.” Inventions 9(5), 97 (2024). doi: 10.3390/inventions9050097.

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