Project PR91 Die-Cast Wave-Fin Aluminum Housing

Functional Heat-Sink Cover for Industrial Motion Control

This case study presents a die cast aluminum housing with an integrated wave fin heat sink, developed for industrial motion control equipment operating in harsh environments.

Project Type

Die-casting + DFM engineering + casting simulation + CNC secondary operations

Application

Industrial motion control equipment – harsh environment (oil mist, dust, long-term thermal stability)

Material

ADC12 aluminum alloy

Part Size & Weight

242.5 × 150.5 × 42.6 mm~1.18 kg

1. Project Context

This project started from a requirement that looks simple on paper but is difficult to execute correctly in reality:

The customer needed an aluminum enclosure that is also a functional heat sink, used in precision industrial motion-control systems. Thermal stability, rigidity, sealing integrity, and long-term reliability were non-negotiable.

At the same time, the part had to go beyond a purely industrial look.The external surface needed to be visually distinctive, clean, and recognizable — not just “another aluminum box”.

The result was a wave-fin heat-sink geometry: a surface that is both functional (heat dissipation) and aesthetic (product signature).

2. Customer Requirements (Summary)

• Die-cast aluminum housing with integrated heat-sink fins

• High thermal efficiency and mechanical rigidity

• Tight sealing surfaces (oil- and dust-resistant enclosure)

• No deformation during assembly

• High cosmetic quality on visible surfaces

• Production-ready solution:design → tooling → samples → stable mass production

3. Why This Was Not a Simple Die-Cast Part

This component sits at the intersection of three demanding disciplines:

1. Industrial designWave-fin aesthetic, clean lines, strong visual identity

2. Mechanical & thermal functionHeat dissipation, flatness, stiffness, sealing reliability

3. Die-casting realityMetal flow behavior, air entrapment, shrinkage, tool life, steel strength

If these are not engineered together, typical failure modes include:

• sink marks and surface waviness

• internal gas porosity (often visible only after finishing)

• weak zones and thin steel in the mold

• sealing failure due to insufficient flatness

From day one, the objective was clear:keep the wave-fin design, but engineer it so it can be cast repeatedly, cleanly, and predictably.

From a manufacturing perspective, this aluminum die casting enclosure combines thermal performance, mechanical rigidity, and sealing precision in a single component.

4. DFM & Casting Simulation – The Core of the Project

Before cutting steel, the project went through a full DFM + casting simulation phase, focusing on:

• Filling behavior across the wave fins

• Solidification sequence and hot-spot detection

• Air-trap and porosity risk zones

• Draft, ejection strategy, and tool-life risks

Key challenge:Average wall thickness ~3.6 mm, with local thickness above 10 mm — a classic recipe for shrinkage and porosity if left unmanaged.

Simulation results were not produced “for documentation”.They directly drove design decisions.

Extensive casting simulation was used to analyze metal flow, air entrapment, shrinkage, and solidification behavior before tooling release.

5. Main Technical Risks & Engineering Solutions

1) Air Trapping & Gas Porosity

The wave-fin geometry creates complex converging flow fronts.

Risk:Trapped air → internal porosity → visible defects after finishing or weakened threaded zones.

Solution:

• Optimized gating and overflow positioning

• Dedicated venting strategy

• Local geometry tuning (relief features / controlled openings where needed)

2) Sink Marks & Thick-to-Thin Transitions

Large local mass cools slower and shrinks more.

Risk:Surface sink, internal voids, cosmetic rejection.

Solution:

• Hot-spot identification via simulation

• Local mass reduction where possible

• Geometry relief while preserving the wave-fin design language

3) Tool Life & Mold Robustness

Aesthetic fins often push mold steel to dangerous limits.

Risk:Thin steel, breakage, sticking, excessive tool wear.

Solution:

• Draft optimization (target ~2° in critical zones)

• Strategic radii to reduce stress and erosion

• Fin length and geometry adjustments where steel became too thin

4) Sealing Precision (Oil & Dust Resistance)

Die casting alone is not sufficient for reliable sealing surfaces.

Solution:

• Machining allowances defined early

• CNC secondary operations on critical mating and sealing areas

• Stable referencing and clamping strategy for repeatable CNC results

6. Gating Strategy & Flow Control

Multiple gating concepts were evaluated through simulation.

Trade-off analysis showed:

• One option minimized sink but increased air-trap risk

• Another delivered cleaner filling, fewer air defects, and better surface quality

Given the customer’s cosmetic and finishing requirements, the project prioritized:

• Stable, predictable filling

• Minimal trapped air

• Superior surface quality after finishing

Remaining sink-risk zones were handled through geometry tuning, not defect acceptance.

7. Tooling & First Samples

After design convergence:

• Tooling was released and manufactured

• First samples were produced to validate:

  • real metal flow vs simulation

  • surface quality of wave-fin area

  • dimensional stability

  • CNC feasibility for sealing surfaces

This phase confirmed that the casting + CNC hybrid strategy delivers repeatable results.

8. CNC Secondary Operations – Precision Where It Matters

To guarantee sealing integrity:

• Die casting creates the complex structure

• CNC machining ensures flatness and precision on critical interfaces

This approach is standard in high-end industrial housings where performance matters more than theoretical “as-cast perfection”.

Critical sealing and mating areas were finished through CNC machining of the die cast aluminum housing, ensuring long-term oil and dust resistance.

9. Final Deliverables

The customer received a production-ready solution:

• Finalized die-cast design aligned with industrial design goals

• DFM-optimized geometry validated by simulation

• Proven gating and venting concept

• Manufactured tooling and first samples

• Defined CNC post-process for sealing precision

• Clear identification of critical-to-quality zones

10. Why This Case Matters

This project is a clear example of engineering done properly.

Not just a metal cover — but:

• a thermal component

• a protective enclosure

• an industrial design statement

Made manufacturable through:

• DFM discipline

• simulation-driven decisions

• correct use of CNC where precision is non-negotiable

Start a pilot run