A Guide To Marine Grade Aluminum
Here's a handy comparison chart of Marine Grade Aluminum Alloys.
We often get asked which alloy to use, and the answer is "it depends".
There are three alloys that we generally recommend for hull plating and frames: 5086, 5083, 5052
And two alloys we recommend for extrusions such as flat bar, tee bar, and tubing: 6061-T6, 6063-T52
| Aluminum Grade-Temper | General | Yield strength (psi) | Ultimate Tensile Strength (psi) | Workability | Weldability |
|---|---|---|---|---|---|
| 5052-H32 | Marine grade. Most suited for forming operations, very good corrosion resistance. Suitable for fresh water and trailered boats. | 28,000 | 33,000 12% elong. | Fair | Good |
| 5083-H321 (Recommend H116) | Marine grade. The highest strength non-heat-treatable aluminum alloy in commercial use. It retains excellent tensile strength in the weld zone. Excellent corrosion resistance. Suitable for salt water or fresh | 33,000 | 46,000 16% elong. | Good | Excellent |
| 5086-H32 | Marine grade. Medium to high strength non-heat-treatable alloy. More formable than 5083. Excellent corrosion resistance. Most often used to build boat hulls (in addition to 5052 or 6061) due to stress corrosion cracking resistance. Best alloy for salt water. | 30,000 | 42,000 12% elong. | Excellent | Good |
| 6061-T6 | Marine grade, often used as stiffeners to build boat hulls and other components. The most often used aluminum alloy for its strength, heat treatability, workability and weldability. | 40,000 | 45,000 17% elong. | Good | Good |
| 6063-T52 | Softer and lower strength than 6061, good for forming, high surface finish, excellent for anodizing. Good for railings, gunnels etc. where forming is required | 21,000 | 27,000 | Good | Good |
| 6262-T6511 | Used when significant machining is required, it contains lead and bismuth to partially lubricate the cutting tool. Good strength and corrosion resistance. High surface finish possible. | 27,600 | 31,900 | Excellent | Good |
