BS L 109-1971 pdf download.Aluminium-coated sheet and strip of aluminium-copper- magnesium-manganese alloy
NOTE 1 Material to this British Standard, if subsequently solution treated or annealed, may develop coarse grain and may show pronounced “orange peel” on subsequent manipulation. Also, particularly with thin material, repeated solution treatment will reduce the corrosion resistance and impair the colour. If substantial manipulation is necessary, it is therefore desirable that material should be purchased in the as-rolled condition to BS L 110.
NOTE 2 Attention is drawn to the warning contained in Clause 6.1.
NOTE 3 Other forms of material of similar basic composition are covered by the following British Standards:
BS L 110, Aluminium-coated sheet and strip (supplied for solution treatment by the user).
BS L 97, Plate (solution treated, controlled stretched and aged at room temperature).
BS L 98, Plate (solution treated, and aged at room temperature: not controlled stretched).
NOTE 4 The chemical composition of the core of this material is similar to that registered as International Designation 2024 and the chemical composition of the cladding complies with that
registered as International Designation 1050A.
1 Inspection and testing procedure This British Standard shall be used in conjunction
with Sections 1 and 9 of BS L 100.
2 Quality of material
2.1 The sheet and strip shall consist of a core of the alloy specified in 3.1 coated uniformly on both sides with aluminium of the chemical composition specified in 3.2. The minimum average thickness of the cladding on each side shall be 4 % for material up to and including 1.6 mm thick and 2 % for thicker material.
2.2 The core material shall be made from aluminium and alloying constituents, with or
without approved scrap, at the discretion of the manufacturer.
4 Condition The material shall be supplied solution treated, straightened and aged at room temperature.
5 Heat treatment The material shall be heat treated as follows: 1) Solution treat by heating at a temperature of 495 ± 5 °C and quenching in water at a temperature not exceeding 40 °C. 2) Age at room temperature for not less than 48 hours.
6 Mechanical properties
6.1 Tensile test 1) . The mechanical properties obtained from test pieces selected and prepared in
accordance with the relevant requirements of BS L 100 shall be not less than the following values:
7 Identification
The requirements relating to “all over” marking in BS L 100, Section 9, shall apply.BS L 109 pdf download.