Aluminum CNC Machining

Aluminum is the most widely processed lightweight metal in CNC machining. With a density of just 2.7 g/cm³, roughly one-third of steel, it offers an excellent strength-to-weight ratio. At the same time, aluminum can be machined at cutting speeds of up to 800 m/min, enabling short cycle times and cost-effective production.

In modern manufacturing, aluminum is used across virtually all industries: aerospace, automotive, medical technology, mechanical engineering, and electronics. Its good corrosion resistance through a natural oxide layer, excellent thermal conductivity, and the ability to be anodized make aluminum a true all-rounder.

In practice, all common aluminum alloys are machined. The most frequently requested are EN AW-6082 (mechanical engineering) and EN AW-7075 (high-strength). → CNC Milling

Due to its low strength and high thermal conductivity, aluminum allows significantly more aggressive cutting data than steel:

Pro tip: For best surfaces on aluminum: use polished solid carbide end mills with 2 flutes, run high RPM, and use climb milling. Built-up edge formation is prevented by high v_c and sharp tools.

Aluminum offers a wide range of surface finishing options:

• Anodizing, Hard oxide layer (5-25 µm), color options, corrosion protection. Standard for visible parts.
• Hard Anodizing, Thicker layer (25-100 µm), extremely wear-resistant (HV 400-500). For functional surfaces.
• Chromating, Thin corrosion protection, electrically conductive. For electronics housings.
• Powder Coating, RAL colors, robust, UV-resistant. For outdoor applications.
• Electroless Nickel Plating, Uniform coating even inside bores. For wear protection.

Specify the required surface treatment in your enquiry. We place the job with partner shops that provide it.

To ensure your aluminum parts can be manufactured optimally, follow these design guidelines:

• Wall thickness: Minimum 0.8 mm for milled parts, 0.5 mm for turned parts. Thinner walls vibrate and deform under cutting pressure.
• Internal radii: Provide at least half the end mill diameter as internal radius. 90° corners require expensive EDM.
• Threads: Minimum 1.5×D engagement depth (aluminum is softer than steel). Thread inserts (Helicoil) for frequently assembled joints.
• Fits: H7/h6 fits are easily achievable. For press fits: consider the thermal expansion coefficient (23.1 × 10⁻⁶/K).
• Deep pockets: Depth-to-width ratio max 4:1 for stable machining. Deeper pockets increase machining time exponentially.

Tip: Send us your drawing. Specialists from our team check manufacturability for free, suggest optimizations and place the job with a suitable partner shop. → Contact

Aluminum can be machined to very tight tolerances:

Important: Aluminum has a high thermal expansion coefficient (23.1 × 10⁻⁶/K). For parts with tight tolerances, measuring temperature should be 20±1°C. A 200 mm aluminum part changes length by 0.046 mm with a 10°C temperature difference.

• Aerospace, Structural components, fuselage parts, seat brackets from EN AW-7075 and EN AW-2024. Highest strength requirements at minimal weight.
• Automotive, Motor mounts, transmission housings, cooling system components. Increasingly e-mobility: battery housings and inverters from aluminum.
• Mechanical Engineering, Guide rails, base plates, adapter plates from EN AW-6082. Universally applicable.
• Medical Technology, Housings for medical devices, operating table components. Anodized for hygiene and aesthetics.
• Electronics, Heat sinks, 19" rack enclosures, housings. Aluminum conducts heat 4× better than steel.
• Optics & Metrology, Carrier plates, adjustment elements. EN AW-6082 T651 stress-relieved for highest dimensional stability.