Aluminium

Aluminium

Products
Round, Flat, Square, Hexagon, Tee, Channel, Angle, Special Extrusions.Flanges, Welded Pipe, Extruded Pipe..Hollow Bar.Sheet, Plate, Strip In Coil.Box Section, Rectangular Section.Tread PlateForgingsCastingsSpecials To Order
Grades
1350A     (1E)1050A     (1B)1200        (1C)2011        (FC1)2014A     (H15)20303103        (N3)5005A     (N41)5251        (N4)5754        (N5)6061        (H20)6063        (H9)6082          (H30)6262
Services
Shearing, Plate Sawing, Plate Circle Cutting, Bar/Tube Sawing, Polishing, Bar Boring, Folding & Rolling, Machining

Aluminium is an important material in a large cross section of industries. It is suitable for forming, welding and machining and provides the following advantages;

  • Non – Magnetic
  • Good electrical conductivity; about 60% that of Copper but reduced by the presence of alloying elements
  • Highly economic to recycle
  • High specific strength
  • High corrosion fatigue resistance
  • Low specific gravity approximately 1/3 of steel

Although available in a number of grades, Aluminium can be divided into two major categories of wrought alloys;

Work Hardening Alloys

These alloys ie., Non heat treatable, include commercially pure aluminium and the alloys including manganese or magnesium. The degree of work hardening is expressed as a temper “H”. these alloys can be fully or partly softened by annealing at 350 – 400 deg Celcius.

Old SymbolNew SymbolDescription
OOAnnealed, soft
FMAs fabricated
H12H2Strain-hardened, quarter hard
H14H4Strain-hardened, half hard
H16H6Strain-hardened, three quarter hard
H18H8Strain-hardened, fully hard
H22H2Strain-hardened, partially annealed, quarter hard
H24H4Strain-hardened, partially annealed, half hard
H26H6Strain-hardened, partially annealed, three quarter hard

Heat Treatable Alloys

Heat treatable alloys or precipitation hardening alloys include copper, magnesium, zinc and silicon as important constituents. For these alloys, the designation system uses the letter “T” following the grade;

T3Solution heat-treated, cold worked and naturally aged to a substantially stable condition. The designation applies to products which are cold worked to improve strength after solution heat-treatment, or in which the effect of cold work in flattening or straightening is recognised in mechanical property limits.
T4Solution heat-treated and naturally aged to a substantially stable condition
T6Solution heat-treated and then artificially aged. The designation applies to products which are not cold worked after solution heat-treatment, or in which the effect of cold work in flattening or straightening may not be recognised in mechanical property limits.
T7Solution heat-treatment and then artificially aged. This designation applies to products which are artificially aged after solution heat-treament to carry beyond the point of maximum strength to provide control of some significant characteristic other than mechanical properties
T8Solution heat-treated, cold worked and then artificially aged. The designation applies to products which are cold worked to improve strength, or in which the effect of cold work in flattening or straightening is recognised in mechanical property limits.
T9Solution heat-treated, artificially aged and then cold worked. This designation applies to products which are cold worked to improve strength.
T651Solution heat-treated, stress relieved by stretching a controlled amount (permanent set 0.5% to 3% for sheet; 1.5% to 3% for plate; 1% to 3% for rolled or cold-finished rod and bar) and then artificially aged. The products receiev no further straightening after stretching.

European Specifications with British Standard Comparison

EN NumberContentBS1470:1987BS1474:1987
EN 485-1Technical conditions for inspection and delivery**
EN 485-2Mechanical Properties**
EN 485-3Tolerances on shape and dimensions for hot rolled products**
EN 485-4Tolerances on shape and dimension for cold rolled products**
EN 515Temper designations****
EN 573-3Chemical composition****
EN 573-4Forms of products****
EN 755-1Technical conditions for inspection and delivery**
EN 755-2Mechanical properties**
EN 755-3Round bars, tolerances on dimension and form**
EN 755-4Square bars, tolerances on dimension and form**
EN 755-5Rectangular bars, tolerances on dimensions and form**
EN 755-6Hexagonal bars, tolerances on dimension and form**
EN 755-7Seamless tubes, tolerances on dimension and form**
EN 755-8Porthole tubes, tolerances on dimension and form**
EN 755-9 *Profile tolerances on dimension and forms**

(*) = Due for publication      (**) = How European relates to old British Standards