Choose 6061-T6/T651 for strength, stiffness, and machining (frames, brackets, precision plates).
Choose 5052-H32 for bending/forming and corrosion resistance (marine covers, boxes, enclosures).
Both anodize and weld; density is essentially the same. The real trade is strength vs formability—plus which manufacturing process you’ll use.
What are 6061 and 5052, and how are they hardened?
- 6061 is a 6xxx Mg–Si, heat-treatable alloy (solution heat treat + artificial age to T6; T651 adds stress-relief for machining stability).
- 5052 is a 5xxx Mg, non-heat-treatable alloy that strengthens by work hardening (H32/H34).
Typical forms: 6061 (plate, bar, extrusions, tube); 5052 (sheet/coil, plate).
At-a-glance
| Alloy | Family | Hardening method | Common tempers | Typical forms |
|---|---|---|---|---|
| 6061 | 6xxx (Mg–Si) | Heat-treated (T-tempers) | T6, T651 | Plate, bar, extrusions, tube |
| 5052 | 5xxx (Mg) | Work-hardened (H-tempers) | H32, H34, O | Sheet/coil, plate |
How does strength compare in real parts?
- 6061-T6/T651 delivers higher yield/UTS and better fatigue; it’s the pick when sections carry load, hold threads, or need stiffness over a span.
- 5052-H32 has lower tensile but is plenty strong for formed sheet and panels—geometry (ribs, flanges, hems) supplies the stiffness.
Why does 5052 bend better than 6061?
Metallurgy + temper. 5052-H32 has higher ductility in brake-forming; 6061-T6 tends to crack at tight radii.
How to bend 6061 safely: form in T4/T42, then re-age to T6 to recover strength.
Do / Don’t
- Do use generous inside radii on 6061; deburr and lubricate heavy bends.
- Don’t force tight bends in 6061-T6; Don’t ignore grain direction on thick sheet.
How should you weld 6061 and 5052, and which filler works?
Both TIG/MIG weld well. Your filler choice matters:
- 4043 → excellent crack resistance on 6061; welds may anodize a different shade.
- 5356 → higher joint strength and better anodize color match; common for 5052 and many 6xxx joints.
For marine weldments, 5052 + 5356 is a practical default.
How do they handle corrosion, especially in marine use?
- 5052 is the safer bet in salt spray/marine environments.
- 6061 performs well when you finish properly (conversion coat + paint or anodize) and avoid unsealed crevices.
How do they machine, hold tolerance, and stay flat?
- 6061-T651 is the CNC workhorse—stiff, stable, easy on tools, great for tapped holes and milled pockets.
- 5052 is softer/gummier; it machines acceptably for holes/slots after forming the box, but it’s not the first choice for heavy CNC.
What finishes and anodizing results can you expect?
- 5052: uniform decorative anodize with good protection.
- 6061: solid decorative anodize and excellent hardcoat for wear surfaces.
- If color uniformity across welds matters, 5356 filler usually blends better than 4043.
Does price or weight differ in practice?
- Weight: essentially the same density; design geometry drives weight.
- Price: market-dependent. 5052 sheet often wins for bent enclosures; 6061 plate/bar is widely available and economical for CNC parts.
How should you choose the process—sheet/plate, CNC, or die casting?
061/5052 are wrought alloys. For boss-rich, thin-wall 3D housings at volume, many teams switch to aluminum die casting (A380 / ADC12 / AlSi10Mg) and post-machine the datums.
Process matrix
| Criteria | 6061/5052 Sheet & Brake | CNC from 6061 Plate/Bar | Al Die Casting (A380/ADC12/AlSi10Mg) |
|---|---|---|---|
| Geometry | Panels, U-channels, boxes | Any 3D, thick sections | Complex 3D, thin walls, ribs, bosses |
| Tolerance | Good; add beads/hems | Excellent | Good → post-machine datums |
| Finish | Anodize/powder; 5052 bends look clean | Anodize/hardcoat | Shot/polish + coating; textures |
| Tooling | Low | None | High (mold), amortized at volume |
| Per-part cost @ volume | Low–medium | High | Low at medium–high volume |
| Lead time | Fast | Fast | Medium (tooling) |
How do you integrate sheet/plate parts with die-cast housings?
We often pair 6061/5052 covers and brackets with A380/ADC12/AlSi10Mg housings.
- How to join: bolt to steel inserts in the casting; add structural adhesive where peel resistance helps.
- How to sequence: weld sheet-to-sheet first, then fasten to the casting (keep heat out of the casting).
- How to protect: anodize the sheet; conversion-coat/paint the casting; use isolation washers/shims to manage galvanic couples.
- How to hold tolerance: keep datums on machined 6061 plate; design locating pads into the casting; use slotted holes to absorb thermal growth.
What do buyers ask most (quick FAQ)?
What is stronger, 6061 or 5052?
6061-T6/T651—better yield/UTS and fatigue for frames and tapped holes.
Why pick 5052 for bending?
It tolerates tight radii and forms cleanly (H32), ideal for boxes and deep flanges.
How should I weld them?
Both TIG/MIG; 4043 for crack resistance on 6061, 5356 for strength and color match (great with 5052).
How do I protect parts outdoors or at sea?
Use 5052 by default for marine; or finish 6061 well (conversion coat + paint or anodize) and seal crevices.
Can I start in sheet/CNC and later die cast?
Yes—prototype in 5052/6061; scale to A380/ADC12/AlSi10Mg and post-machine critical features.
Need a recommendation?
Send your drawing and expected volume. We’ll mark bend radii, choose filler metal, and advise 6061, 5052, or die casting—with DFM notes and a fast quote.
