Zero Gap Installation: Why Your Thermal Interface Material Just Became Optional This is a CNC-machined aluminum or copper heat sink engineered for applications where every 0.1°C/W matters. The flatnes
This is a CNC-machined aluminum or copper heat sink engineered for applications where every 0.1°C/W matters. The flatness tolerance on the mounting surface is held to 0.02 mm across the entire footprint, and the surface finish is Ra 0.8 µm. That combination creates a physical zero gap between the heat sink and your component—no thermal paste, no pad, no clamping force variations. In our lab tests, this reduced junction-to-sink thermal resistance by up to 18% compared to a standard milled sink with Ra 3.2 µm. You get predictable thermal performance straight from the drawing, not from the technician's hand.
We do not guess thermal performance. Every heat sink design is simulated using finite element analysis (FEA) before we cut metal. For a given fin height, fin thickness, and base plate thickness, we can hold thermal resistance within ±5% of your target value. If you need 0.12°C/W at 1 m/s airflow, we machine the geometry to deliver that exact number. We have produced heat sinks for IGBT modules, laser diodes, and EV battery chargers where the thermal budget was non-negotiable. Our 20-year-old factory in Dongguan has the CNC capacity to hold fin pitch to 1.5 mm with a 0.05 mm tolerance, which is what makes precise thermal control possible.
Choose your base material based on your thermal and mechanical load. For most power electronics, we recommend 6061-T6 aluminum: it gives you a hardness of 95 HRB, good machinability, and a thermal conductivity of 167 W/m·K. If you need higher corrosion resistance or anodizing quality, 6063-T5 is softer (73 HRB) but extrudes cleaner and finishes to a more uniform Ra 0.4 µm. For maximum dissipation—think high-density LED arrays or RF amplifiers—C1100 copper offers 391 W/m·K but weighs 3.3 times more. We machine all three in-house. We also offer nickel-plated copper for solderable surfaces. Tell us your operating temperature and ambient airflow; we will specify the material and hardness in your drawing.
Thin fins are where most CNC shops fail. We use 4-axis and 5-axis machining centers with through-spindle coolant at 80 bar pressure. This prevents chip welding and keeps the fin surface free of burrs. Our standard fin thickness is 1.2 mm, but we can go down to 0.8 mm with a height-to-thickness ratio of 20:1. The runout on the cutting tool is held to 0.005 mm, which is why we can machine a 40-fin array with a total width tolerance of ±0.1 mm. We do not use EDM for fins—it leaves a recast layer that reduces heat transfer. Pure milling, always.
Every heat sink gets a full dimensional check before it leaves our floor. We use a coordinate measuring machine (CMM) with a resolution of 0.001 mm to verify all critical mounting dimensions. Surface finish is measured with a profilometer, not eyeballed. Flatness is checked on a granite surface plate with a dial indicator. The inspection report—including thermal simulation results—is shipped with your parts, and the report is also available as a PDF for your incoming QC. If a dimension is out of spec, we recut it at no cost. We have not shipped a defective heat sink in the last 14 months.
Prototype heat sinks are machined in 7 business days from drawing approval. Production runs of 100 to 10,000 pieces ship in 15 to 20 days. There is no MOQ—we accept a single-piece order for testing. This is possible because our factory in China runs 24/7 and stocks 6061-T6 and C1100 blanks in standard sizes. For urgent requirements, we can expedite a prototype in 72 hours with a 20% rush surcharge. The price per unit drops predictably: a 100 x 100 x 20 mm aluminum sink costs roughly $3.50 each at 100 pieces, $2.20 each at 1,000 pieces, and $1.80 each at 5,000 pieces.
Bare aluminum is rarely the final answer. Clear anodize (8–12 µm thickness) increases surface emissivity from 0.09 to 0.77, which improves radiative cooling by up to 40%. Black anodize adds another 5% on top of that. For copper, we recommend electroless nickel plating (5–10 µm) to prevent oxidation and maintain solderability. All treatments are done in our partner facility 3 km from the factory, so there is no cross-border shipping delay. If you need a specific military or automotive finish, send your spec sheet and we will match it.
| Specification | Value | Notes | | --- | --- | --- | | Base Material | 6061-T6, 6063-T5, C1100 Copper | Copper optional | | Hardness (Aluminum) | 73–95 HRB | Depends on alloy | | Thermal Conductivity | 167–391 W/m·K | Aluminum to copper | | Flatness (Mounting Surface) | ±0.02 mm | Across full footprint | | Surface Finish (Ra) | 0.4–0.8 µm | As machined or after treatment | | Fin Thickness | 0.8–3.0 mm | Minimum 0.8 mm | | Fin Pitch | 1.5–8.0 mm | ±0.05 mm tolerance | | Runout (Tool) | 0.005 mm | Ensures straight fins | | Lead Time (Prototype) | 7 business days | 72-hour rush available | | MOQ | No minimum | Single piece accepted |There is no MOQ—we machine a single prototype for your testing, and production pricing starts at 100 pieces.
Yes, we run FEA simulation on your geometry and hold thermal resistance within ±5% of the target, verified in our test report.
We hold flatness to 0.02 mm and surface finish to Ra 0.8 µm, which eliminates the need for thermal paste in most applications.
Production runs of 1,000 pieces ship in 15–20 days after drawing approval, and we send a CMM report with every shipment.
Before you finalize your heat sink design, check our CNC cutting tool selection guide to understand how tool geometry affects fin quality. Also, review CNC machining tolerances guide to ensure your drawing communicates the right limits for thermal performance.
Stop waiting for vague estimates. Send us your STEP or IGES file, your target thermal resistance, and your annual volume. Our engineers will respond within 12 hours with a firm unit price, tooling cost (if any), and a confirmed lead time. This is precision manufacturing made in China, with zero MOQ and zero surprises. Email your drawing to sc@bquq.com or message us on WhatsApp at +86 13713157787. We start machining as soon as you approve the quote.
| Parameter | Capability |
|---|---|
| Materials | AL6063/6061/5052, pure copper C1100, copper-aluminum composite |
| Process | Extrusion, CNC machining, skiving, forging, die casting, stamping fins |
| Fin Types | Extruded, pin fin, skived, folded, bonded, heat pipe, vapor chamber |
| Surface | Black anodizing, clear anodizing, nickel plating, powder coating |
| Size Range | Max 1500 x 400 x 300 mm |
| Thermal Test | Thermal resistance and heat dissipation data per batch |
| Prototype | 5-7 days, no MOQ on samples |
| Inspection | CMM, thermal resistance tester, full report per batch |
