Aluminium Materials
Aluminium Plates or Sheets
Aluminium Plates or Sheets is a group of 42 IMPA-coded items (codes 673101–673171) under Aluminium Materials in the Metal Sheets, Bars, Etc. section (IMPA 67). All of them are priced per sheet. Every item in the list is aluminium. The list runs through 22 metric sizes from 0.2 mm to 2000×5 mm.
Buying guide
This group holds aluminium sheet by thickness, from 0.2 mm to 12 mm, in two sheet sizes: 400 × 1200 mm and 1000 × 2000 mm. The IMPA descriptions give only thickness and size. They do not name an alloy or temper.
Thin sheet goes into the ship’s own work: shims, covers, guards, insulation cladding, ducting and signs. Thicker plate is used for small fabrications and repairs. The chief engineer or bosun orders it for a job, usually alongside rivets or fasteners.
How to specify it
Because the catalogue line names no alloy, add one to the requisition, or the offers will not be for the same material. Wrought aluminium alloys are numbered in four-digit series by their main alloying element. 1xxx is essentially pure aluminium (at least 99 %). 3xxx is alloyed with manganese, 5xxx with magnesium and 6xxx with magnesium and silicon. The 5xxx alloys are the ones known for corrosion resistance in marine use.[1]
Give the temper after the alloy. IACS UR W25 bases alloy and temper designations on those of the Aluminium Association, with tempers defined in EN 515 or ANSI H35.1. A full description reads like "5083 H111, 3 mm, 1000 × 2000 mm". Then add the number of sheets.[2]
Mind the other metals in the job. Galvanic corrosion can occur when aluminium is in electrical contact with metals of more positive corrosion potential, where an electrolyte is present. Seawater and wet decks provide one.[1]
Rules and certificates
Aluminium for hull, superstructure and other marine structures is a class matter. IACS UR W25 covers rolled products 3 mm to 50 mm thick in alloys 5083, 5086, 5383, 5059, 5754 and 5456. The tempers covered are O, H111, H112, H116 and H321. The material has to come from works approved by the classification society for the grade. IACS lists Rev.6 (September 2021) as the current revision.[2][3]
Under the same requirement, rolled 5083, 5383, 5059, 5086 and 5456 for hull use or frequent seawater contact are corrosion tested for exfoliation and intergranular attack. Tested tempers are marked with an "M", for example 5083 H321 M. Each product is marked with the maker’s mark, alloy, temper and batch number, and a test certificate covers each batch.[2]
Sheet from this group is not a substitute for class-certified plate in a structural repair. Agree the alloy, temper and certificate with class before ordering for that use.[2]
Questions buyers ask
- Which aluminium alloy is marine grade?
- For hull and marine structures, IACS UR W25 lists the 5xxx alloys 5083, 5086, 5383, 5059, 5754 and 5456 for rolled plate and sheet. 5083 is the common one. It notes that 6005A and 6061 extrusions should not be in direct contact with seawater unless protected by anodes or paint.
- Can I put aluminium sheet in contact with steel or copper?
- Avoid it where water can get in. Aluminium in electrical contact with a more noble metal and an electrolyte can corrode galvanically.
Sources
Published by Sherif Awad, founder of GeoMarineHub — in ship supply since 1990, a family business since 1981 (45 years). Last checked .
At a glance
Part of Metal Sheets, Bars, Etc. (IMPA section 67): Stock steel, stainless, aluminium, brass and copper — plates, sheets, bars, angles, flats and mesh.
It is one of 4 groups under Aluminium Materials; the others include Aluminium Hexagons, Aluminium Rounds, Aluminium Squares.
Post the ones you need as a requirement and verified suppliers activated at your port bid on them — sealed, so nobody sees another bid.
- Items
- 42
- IMPA codes
- 673101–673171
- Priced
- per sheet
- Materials
- aluminium
- Sizes
- 0.2 mm – 2000×5 mm
Items
Also under Aluminium Materials
Most requested sections