1. Scope
This national standard specifies terms, sample selections, sampling rules, sample preparation, sample quantity, storage and resample involved with method of sampling for analyzing the chemical composition of wrought aluminium and aluminium alloy.
This standard is applicable to sampling method of samples for analyzing chemical compositions of cast ingot and its processed products of wrought aluminium and aluminium alloy (plate, sheet, strip, foil, tube, rod, section, wire and forgings).
2. Terms
2.1 Portion
Product part cut from the cast ingot or processed products for preparing samples; or partial bath taken from casting or rolling stabilization
2.2 Sample
Chipping mechanically or manually processed by portion; it is used as the ultimately material form (drill chip, milling chip and shearing chip) when carrying out the chemical analysis.
3. Portion Selection
3.1 Selection principle
3.1.1 In casting or rolling steady stage of aluminium and aluminium alloy, the manufacturing plant select the portion representing the components, and it shall take from the production during the arbitration stage.
3.1.2 The portion representing the round lot or whole purchase contract shall be selected randomly. In ensuring its representativeness, the portion shall select the one with minimum spillage of material.
3.1.3 The buyer may use tension sample after breakage as the selected portion.
3.2 Sampling quantity
3.2.1 If the portion is from the casting or rolling steady stage, when bath composition in the melt furnace is even, each fusing bath shall take at least one portion.
3.2.2 When the portion is taken from the products of the same grade and same batch, unless otherwise specified, it shall be sampling by the following requirements generally.
a) Cast ingot, one casting batch shall take one portion;
b) One portion shall be taken from per 2000kg plate, sheet and strip, and one from per 500kg foil; for tape volume foil volume with single volume weight of greater than the normal weight, each volume may take one portion;
c) One portion shall be taken from per 1000kg tubes, rod, section and wire;
d) When the forging is less than or equal to 2.5kg, each 1000kg product shall take one portion; while the forging of greater than 2.5kg, one portion shall be taken from 3000kg product;
e) The product less than the normal weight shall take another portion.
GB/T 17432-1998 The following standards are cited：
