Aluminum CNC Machined Parts — 6061 & 7075

Grades we machine

We machine aluminum machined parts from four grades on our own floor in Qidong, Jiangsu Province: 2024, 5052, 6061, and 7075. They cover most of the aluminum work we quote, and the choice comes down to strength, corrosion resistance, weldability, and how the part will be finished.

• 6061 aluminum is the general-purpose grade. It machines cleanly, welds well, resists corrosion, and anodizes evenly, which makes it the default for housings, brackets, and enclosures. It is the most affordable of the three and the easiest to specify.
• 7075 aluminum is a high-strength alloy that approaches some steels in strength while staying light. It is specified for stressed, lightweight parts where strength and fatigue matter. It offers less corrosion resistance than 6061 and is not a welding alloy, so it is usually anodized or coated for protection.
• 2024 aluminum is the fatigue-performance grade, widely used where parts cycle under load. It delivers high strength and excellent fatigue resistance, at the cost of lower corrosion resistance than 6061. It is often used in clad form, where a thin surface layer of purer aluminum protects the core.
• 5052 aluminum is the non-heat-treatable grade. It is not selected for strength — 6061 is stronger — but for its corrosion resistance, formability and weldability, which is why it turns up in marine hardware, fuel and fluid tanks, and sheet-metal work. It is supplied in the H32 temper rather than a T condition, and it welds and bends more readily than the heat-treatable alloys.

Temper is part of the specification, not a detail to skip. 6061 is usually supplied in T6 or T651, while 2024 and 7075 are commonly supplied in T4 or T351 for better machinability or formability. These conditions are not interchangeable: the same alloy in a different temper machines, finishes, and behaves differently. When you request a quote, state the alloy and temper together, and we will confirm them against the drawing within 24 hours.

If the drawing leaves the alloy open, tell us how the part is loaded, exposed, and joined, and we will suggest the grade and temper in DFM feedback. Sending the alloy and temper together avoids rework later: a part quoted in 6061-T6 does not simply swap to 7075-T6 without changing how it machines, finishes, and costs.

Machining characteristics of aluminum machined parts

Aluminum is one of the easiest metals to machine. It cuts quickly with lower tool wear than steel or stainless, so our aluminum machining services reach tight tolerances and smooth finishes at lower cost. We hold ±0.01 mm on precision features and work to ISO 2768-m as the general tolerance unless your drawing states otherwise.

The trade-off is stability. Thin walls and large flat faces can deflect or spring back, so we manage clamping pressure and cut sequence to keep parts flat and true. Fine threads also gall easily, so we control feeds and thread passes. 7075 and 2024 are stronger and stiffer than 6061, which helps hold fine features, but both are more abrasive and cut a little slower than 6061, so we plan tooling and speeds per grade rather than treating all aluminum the same.

Because aluminum machines fast, the cost difference between a loose and a tight tolerance is smaller than in stainless or titanium. We return DFM feedback with your quote within 24 hours so you can see where tolerance and thin sections drive the price, and orders start at 50 pieces per style and material.

Aluminum also chips freely, so we clear chips from deep pockets and small holes to protect the surface and keep the cutter engaged. Coolant and speeds are matched to the grade, because 7075 and 2024 run hotter and wear inserts faster than 6061 even though all three cut fast by steel standards.

Typical parts made from this material

Because it is light, stiff for its weight, and easy to machine, aluminum covers enclosures, housings, brackets, and thermal parts. The grade follows the load:

• Enclosures and housings and brackets in 6061, where weldability and anodizing quality matter.
• Heat sinks where thermal conductivity and light weight matter, usually 6061.
• Spacers and standoffs and knobs for equipment hardware.
• Gears and shafts in 7075 where strength is required, or 2024 where the part cycles under fatigue load.
• Structural and load-bearing plates in 7075 or clad 2024, depending on the drawing.

Orders start at 50 pieces per style and material, samples are available from 1 piece, and a material certificate (MTR) ships with every batch.

Surface finishes that pair well

Aluminum is the material most associated with anodizing, and most anodized aluminum parts we ship are 6061, 7075, 2024 or 5052. The anodizing aluminum process grows a protective oxide layer that takes dye, giving the classic anodized aluminum finish. Finishing is applied through our vetted partner network, managed under one quality process.

Anodizing behaves differently across the grades. 6061 anodizes evenly to a clean, uniform finish, which is why it is the default for dyed and clear anodized aluminum parts. 7075 anodizes to a darker, slightly less uniform tone because of its copper and zinc content, so it is usually specified in darker colors or used where appearance is secondary to protection. 2024 also contains copper and anodizes unevenly, which is one reason it is often used clad or with a conversion coating instead. Type II is the everyday anodizing for cosmetic and light protective use, while Type III builds a thicker, harder layer for wear surfaces; we match the type to the alloy and the drawing.

• Anodizing — the standard anodized aluminum finish, available clear or dyed; specify the color carefully on 7075 and 2024.
• Alodine conversion coating — a thin conductive finish where parts must stay electrically conductive, often used on 2024 and 7075.
• Powder coating — a thicker, colored coating for housings and panels where appearance matters.
• Sand blasting and polishing and brushing — textures and directional finishes, often applied before anodizing.

If the drawing calls for a specific finish, tell us the alloy, temper, and finish together and we will confirm the combination works before we quote.