CNC Machining 2025 (AlCu5Mn) — 2xxx Series Material
This article provides essential technical information about 2025 (AlCu5Mn), a high-strength aluminum alloy from the 2xxx series, alloyed with copper (Cu) and manganese (Mn). 2025 is specifically designed for forged and machined components requiring a combination of moderate strength, good ductility, and excellent machinability. It is commonly used in aerospace, automotive, and industrial applications where parts are produced by hot forging followed by CNC machining. Dongguan Stirling Metal Products Co., Ltd. specializes in machining 2025 for structural components and custom parts demanding high reliability.
Chemical Composition (ASTM B211 / EN 573-3)
| Element | Content (%) | Role |
|---|---|---|
| Aluminum (Al) | Balance (approx. 91.5 – 94.5) | Base metal |
| Copper (Cu) | 4.0 – 5.0 | Primary strengthening element; precipitation hardening |
| Manganese (Mn) | 0.50 – 1.20 | Improves strength and grain structure control |
| Silicon (Si) | ≤ 0.50 | Impurity; affects ductility |
| Iron (Fe) | ≤ 0.50 | Impurity; controlled for toughness |
| Magnesium (Mg) | ≤ 0.05 | Trace |
| Zinc (Zn) | ≤ 0.10 | Trace |
| Titanium (Ti) | ≤ 0.15 | Grain refiner |
| Others (each) | ≤ 0.05 | – |
| Others (total) | ≤ 0.15 | – |
Mechanical Properties (Typical, T6 Temper)
| Property | Value | Standard (ASTM B211) |
|---|---|---|
| Tensile Strength (MPa) | 350 – 400 | ≥ 350 |
| Yield Strength (0.2% offset, MPa) | 250 – 300 | ≥ 250 |
| Elongation (%) | 12 – 18 | ≥ 10 |
| Hardness (HBW) | 100 – 120 | – |
| Shear Strength (MPa) | 210 – 240 | – |
| Modulus of Elasticity (GPa) | 72 | – |
| Fatigue Strength (MPa, 10^7 cycles) | ~120 | – |
CNC Machining Parameters
2025 offers good machinability, similar to 2017 but with slightly higher strength. Use carbide tools with positive rake angles and adequate coolant to manage heat generation. The following parameters are for uncoated or TiB2-coated carbide (ISO K10/K20).
| Operation | Cutting Speed (m/min) | Feed (mm/rev) | Depth of Cut (mm) | Coolant |
|---|---|---|---|---|
| Turning (rough) | 250 – 400 | 0.15 – 0.30 | 1.5 – 3.0 | Water-miscible (5-8%) |
| Turning (finish) | 350 – 500 | 0.08 – 0.18 | 0.2 – 0.5 | Mist or air blast |
| Milling (rough) | 200 – 350 | 0.10 – 0.25 (mm/tooth) | 1.0 – 2.0 | Water-miscible |
| Milling (finish) | 300 – 450 | 0.05 – 0.12 (mm/tooth) | 0.2 – 0.5 | Mist or air blast |
| Drilling | 100 – 180 | 0.08 – 0.18 | – | Water-miscible |
Applications
- Aerospace: Forged structural components, engine mounts, and landing gear parts requiring high strength-to-weight ratio.
- Automotive: Connecting rods, suspension components, and transmission parts produced by hot forging and machining.
- Industrial Equipment: Pump housings, valve bodies, and hydraulic manifolds where pressure integrity is essential.
- Rail & Transportation: Brake system components and coupling parts.
- Custom CNC Parts: Precision-machined prototypes and production runs for demanding mechanical applications.
CNC Machining Tips
Tool Material: Carbide (ISO K10/K20) with TiB2 or DLC coating for aluminum. For high-volume production, PCD tools provide extended life.
Coating: TiB2 reduces built-up edge; DLC provides low friction. Avoid TiAlN as it reacts with aluminum at high temperatures.
Coolant: Water-miscible coolant at 5-8% concentration for roughing; mist or dry for finishing to prevent thermal expansion issues.
Heat Treatment: 2025 is typically used in T6 temper (solution heat treated and artificially aged). For maximum machinability, machine in the T4 temper (solution heat treated only) and then age to T6.
Chip Control: 2025 produces medium-length chips. Use chip breakers and positive rake inserts. Avoid built-up edge by maintaining cutting speeds above 250 m/min.
Surface Finish: Achievable Ra 0.4 – 0.8 µm. For sealing surfaces, use wiper inserts or finishing passes with low feed rates.
Why Choose Professional CNC Machining
Precision CNC machining of 2025 aluminum requires expertise in handling precipitation-hardenable alloys, managing residual stresses from forging, and achieving tight tolerances. Dongguan Stirling Metal Products Co., Ltd. employs advanced 5-axis machining centers, stress-relief processes, and in-process inspection to deliver consistent quality. Our one-stop service includes material sourcing (with MTC), CNC machining, heat treatment, surface finishing (anodizing, chromate conversion), and quality certification. From prototype to production, we ensure your 2025 components meet the highest standards.
Published: 2025-03-21
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