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Views: 0 Author: Site Editor Publish Time: 2026-08-29 Origin: Site
A cold forged heatsink lives or dies by its design details — material grade, fin thickness, draft angle, and porosity control.
This guide gives the practical rules and DFM checks you need before sending a part to tooling.
Table of Contents
A cold forged aluminum heat sink is only as good as its material grade, fin geometry, and the design rules applied before tooling. Get those right and you get a thin-finned, one-piece, high-conductivity part. Get them wrong and you pay for a die that cannot meet temperature.
This guide walks through aluminum grade selection, fin geometry options, and the DFM rules that turn a drawing into a reliable sink. For the process comparison, see our cold forged heat sink complete guide.
Cold forging works best with soft, high-conductivity aluminum. The grades you will meet:
Grade | Conductivity | Strength | Use |
AL1070 | Highest among workable Al | Low (soft) | Best cooling, low stress |
AL6063 | Good | Medium | General sinks, anodizes well |
AL6061 | Good | Higher | Structural, tapped holes |
AL1070 conducts best but is soft; AL6063 and AL6061 are stronger and cheaper and suit most sinks. For the copper question, our copper vs aluminum heat sink guide helps you weigh weight and cost. After forming, anodizing protects and finishes the part — see the anodized aluminum guide.
Cold forging's main edge over extrusion is shape freedom:
11. Straight thin fins — denser than extrusion, good for one-way airflow.
12. Pin fins — surface from many directions, ideal for uneven airflow.
13. Splayed (radial) pin fins — wider capture area, good for round sources.
14. Elliptical and circular fins — low drag, match round modules and drivers.
For LED, power supply, and inverter use, pin and splayed fins are common — covered in our cold forged pin fin application guide.
Fin pitch sets airflow. Too tight and air stalls; too open and you lose surface. Match pitch to your cooling mode: natural convection needs wider pitch, forced air allows denser fins. Fin height trades against envelope — taller fins add surface but also add thermal resistance along the fin, so there is an optimum you find by simulation, not by guessing.
Cold forging holds the base flat, which lowers contact resistance to the chip. Keep the mounting face in the drawing with a clear flatness tolerance, and specify the interface material. A flat, well-loaded base often matters more than a few extra fins.
Rule | Why |
Fix fin pitch to airflow | Avoids stalled or starved airflow |
Keep base flat | Lowers contact resistance |
Share base shape across variants | Cuts tooling cost |
Design fixings in | Threads, clips, inserts in the drawing |
Agree finish and test | Anodizing spec, flatness, thermal check |
If your design needs thin, shaped, high-density fins in a compact height, cold forging beats extrusion on performance and often on total cost once machining is removed. Our cold forging vs extrusion comparison and vs skived fin comparison set the boundaries.
A typical flow: define power and envelope, pick grade and fin geometry, run a thermal check, build the die, sample, verify flatness and finish, then mass produce. For a custom run, our custom aluminum heat sink manufacturer page outlines prototyping to mass production.
Design a cold forged aluminum heat sink by choosing the grade for conductivity vs strength, picking the fin shape for your airflow, and applying DFM rules before the die is cut. Flat base, right pitch, and agreed finish turn the drawing into a sink that holds temperature and cost. Match the process to your real constraints and verify with simulation.
Send us your power, envelope, and airflow and we will return a graded, sized design with a free DFM review.
Q1: Is AL1070 always the best choice?
For pure cooling, yes, but it is soft. If you need tapped holes or rigidity, AL6063/6061 are safer.
Q2: Can cold forging make the fin shapes extrusion cannot?
Yes — pin, splayed, elliptical, and circular fins are cold forging strengths.
Q3: How do I set fin pitch?
By cooling mode: wider for natural convection, denser for forced air. Verify with simulation.
Q4: Does anodizing hurt cooling?
It adds a thin layer with slightly lower conductivity, but corrosion protection usually outweighs it. See the anodized guide.
Q5: When should I use copper instead of aluminum?
When weight and budget allow and you need ~50% better conductivity. See copper vs aluminum.
Q6: Can you run the thermal check for me?
Yes. Send specs and we return a DFM review and thermal analysis within 24 hours, free.
