Introduction
6005 aluminum alloy is a heat-treatable Al-Mg-Si alloy that delivers an exceptional balance of extrudability, medium strength, and corrosion resistance. For manufacturers seeking a material that can be extruded into complex profiles with high productivity while maintaining structural integrity, 6005 offers a distinct advantage over alloys like 6061 or 6063. Its performance in extrusion processes is characterized by lower flow stress at elevated temperatures, allowing for faster ram speeds and reduced die wear. Dongguan Stirling Metal Products Co., Ltd. has extensive experience in processing 6005 aluminum alloy, ensuring that every extrusion meets the precise dimensional and mechanical requirements demanded by modern engineering applications.
Chemical Composition
The chemical composition of 6005 aluminum alloy is carefully controlled to optimize extrudability, strength, and corrosion resistance. Silicon and magnesium are the primary alloying elements, forming Mg₂Si precipitates that provide precipitation hardening. Manganese and chromium are added to control grain structure and improve toughness. Copper is kept low to maintain corrosion resistance, while iron is minimized to reduce the formation of brittle intermetallic phases. The following table presents the standard composition limits and typical values observed in production at Dongguan Stirling Metal Products Co., Ltd.
| Element | Min (%) | Max (%) | Typical (%) |
|---|---|---|---|
| Silicon (Si) | 0.60 | 0.90 | 0.75 |
| Magnesium (Mg) | 0.40 | 0.60 | 0.50 |
| Manganese (Mn) | 0.10 | 0.30 | 0.20 |
| Chromium (Cr) | 0.10 | 0.30 | 0.15 |
| Copper (Cu) | 0.00 | 0.10 | 0.05 |
| Iron (Fe) | 0.00 | 0.35 | 0.20 |
| Zinc (Zn) | 0.00 | 0.10 | 0.03 |
| Titanium (Ti) | 0.00 | 0.10 | 0.02 |
| Aluminum (Al) | Balance | Balance | Balance |
The typical composition shown above reflects the optimized blend used by Dongguan Stirling Metal Products Co., Ltd. to achieve consistent extrusion performance. The silicon-to-magnesium ratio is maintained near 1.5:1 to maximize the volume fraction of Mg₂Si precipitates without forming excess free silicon, which can reduce ductility. Manganese and chromium levels are kept within the specified range to promote a fine recrystallized grain structure during solution heat treatment, enhancing the alloy’s response to artificial aging.
Mechanical Properties
6005 aluminum alloy in the T5 temper (extruded and artificially aged) exhibits a well-balanced set of mechanical properties suitable for structural applications. The alloy provides higher strength than 6063 while maintaining good formability and weldability. The following table lists the key mechanical properties measured at room temperature, based on testing performed in accordance with ASTM B221 and EN 755-2 standards.
| Property | Value | Test Standard |
|---|---|---|
| Ultimate Tensile Strength (MPa) | 260 | ASTM B557 |
| Yield Strength (0.2% offset, MPa) | 240 | ASTM B557 |
| Elongation in 50 mm (%) | 10 | ASTM B557 |
| Brinell Hardness (HB 500/10) | 85 | ASTM E10 |
| Shear Strength (MPa) | 160 | ASTM B769 |
| Fatigue Strength (10⁷ cycles, MPa) | 95 | ASTM E466 |
| Modulus of Elasticity (GPa) | 69 | ASTM E111 |
| Poisson’s Ratio | 0.33 | ASTM E132 |
The mechanical properties of 6005-T5 make it an excellent choice for applications requiring moderate load-bearing capacity with good corrosion resistance. The yield strength of 240 MPa allows for efficient section design in structural frames, while the 10% elongation ensures sufficient ductility for bending and forming operations. Dongguan Stirling Metal Products Co., Ltd. performs tensile testing on every production lot to verify that these properties are consistently achieved, with hardness testing used as a rapid quality check during production.
CNC Machining Parameters
Machining 6005 aluminum alloy requires careful selection of cutting parameters to achieve optimal surface finish, dimensional accuracy, and tool life. The alloy’s medium strength and good chip formation characteristics allow for high cutting speeds, but the presence of silicon can cause abrasive wear on uncoated tools. The following table provides recommended CNC machining parameters for common operations, based on experience at Dongguan Stirling Metal Products Co., Ltd.
| Operation | Cutting Speed (m/min) | Feed Rate (mm/rev) | Depth of Cut (mm) | Tool Material | Coolant |
|---|---|---|---|---|---|
| Rough Turning | 300–400 | 0.20–0.40 | 2.0–4.0 | Carbide (K10/K20) | Water-soluble emulsion |
| Finish Turning | 400–500 | 0.08–0.15 | 0.3–0.8 | Carbide (K10) or PCD | Water-soluble emulsion |
| Face Milling | 350–450 | 0.10–0.25 (mm/tooth) | 1.0–3.0 | Carbide (K20) with TiAlN coating | Flood coolant |
| End Milling (slotting) | 250–350 | 0.05–0.12 (mm/tooth) | 0.5–1.5 (radial) | Carbide (K30) with AlTiN coating | Mist or flood coolant |
| Drilling (Ø6 mm) | 80–120 | 0.10–0.20 | N/A | HSS-Co or carbide | Water-soluble emulsion |
| Tapping (M8) | 10–20 | 1.25 (mm/rev) | N/A | HSS-E with TiN coating | Oil-based lubricant |
For roughing operations, higher cutting speeds combined with moderate feed rates maximize material removal rates while maintaining tool life. Finishing passes should use higher speeds and lower feeds to achieve surface finishes below Ra 1.6 µm. Polycrystalline diamond (PCD) tools are recommended for high-volume production due to their superior wear resistance against the silicon phase. Coolant is essential to prevent built-up edge formation and to maintain dimensional stability through thermal management. Dongguan Stirling Metal Products Co., Ltd. provides pre-machined blanks with consistent hardness, reducing variability in machining performance.
Applications
6005 aluminum alloy is widely used in industries that demand extruded profiles with a combination of strength, formability, and corrosion resistance. In the transportation sector, it is a preferred material for bus and railway car body structures, where its medium strength allows for lightweight construction while meeting crashworthiness requirements. The alloy’s excellent extrudability enables the production of complex hollow profiles with thin walls, reducing the number of welded joints in assembly. In architectural applications, 6005 is used for window frames, curtain walls, and structural glazing systems, where its corrosion resistance eliminates the need for protective coatings in many environments. The electrical industry utilizes 6005 for heat sinks and busbars, benefiting from its good thermal conductivity and moderate electrical conductivity. Offshore and marine applications, such as handrails and ladder systems, rely on the alloy’s resistance to saltwater corrosion. Dongguan Stirling Metal Products Co., Ltd. supplies 6005 extrusions to these industries, offering custom profiles tailored to specific design requirements.
Quality Control
Rigorous quality control procedures are essential to ensure that 6005 aluminum alloy extrusions meet the required specifications. At Dongguan Stirling Metal Products Co., Ltd., every incoming billet is verified using optical emission spectrometry (OES) to confirm the chemical composition against the limits shown in the table above. Samples from each extrusion lot are subjected to tensile testing on a universal testing machine to measure ultimate tensile strength, yield strength, and elongation. Brinell hardness testing is performed on the surface of extrusions as a rapid indicator of proper aging treatment. Dimensional inspection is conducted using coordinate measuring machines (CMM) and laser scanners to verify that profile dimensions, wall thicknesses, and straightness tolerances are within the specified limits. For critical applications, ultrasonic testing is employed to detect internal voids or inclusions. All test results are documented with traceable lot numbers, providing full material certification to customers. This comprehensive quality system ensures that every extrusion leaving the facility meets the highest standards of reliability.
Why Choose Us
Dongguan Stirling Metal Products Co., Ltd. combines decades of metallurgical expertise with state-of-the-art manufacturing capabilities to deliver superior 6005 aluminum alloy extrusions. Our in-house metallurgical team continuously optimizes the alloy composition and heat treatment parameters to enhance extrudability and mechanical performance. We operate a fleet of modern extrusion presses ranging from 800 to 3600 tons, enabling us to produce profiles with cross-sectional areas from 10 mm² to 500 mm². Our CNC machining center is equipped with 5-axis machines capable of holding tolerances as tight as ±0.05 mm, ensuring that finished parts are ready for assembly. We provide end-to-end service, from billet sourcing and extrusion to heat treatment, machining, and surface finishing. Our quality management system is certified to ISO 9001:2015, and we offer full material traceability with mill test reports. By choosing Dongguan Stirling Metal Products Co., Ltd., you gain a partner committed to delivering consistent quality, competitive pricing, and on-time delivery for your most demanding projects.
