GB/T 3880.1-2023Wrought aluminium and aluminium alloy plates, sheets and strips for general engineering - Part 1: Technical conditions of delivery (English PDF)

7.1 Inspection and acceptance

7.1.1 The product shall be inspected by the supplier to ensure that the product quality complies with the provisions of this document and the order sheet (or contract), and a quality certificate shall be filled out.

7.1.2 The purchaser shall inspect the received products in accordance with the provisions of this document. If the inspection results are inconsistent with the provisions of this document and the order sheet (or contract), a written request shall be submitted to the supplier for negotiation between the supplier and the purchaser. Objections related to surface quality and dimensional deviations shall be raised within 1 month from the date of receipt of the product. Objections related to other performance shall be raised within 3 months from the date of receipt of the product. If arbitration is needed, it can be entrusted to a unit recognized by both the supplier and the purchaser, and sampling can be done jointly by the purchaser.

7.2 Batching Products shall be submitted for acceptance in batches. Each batch shall be composed of products of the same designation, condition, size specifications and blank opening method. There is no limit on batch weight. If the purchaser requires batches based on melting times and heat treatment heats (or continuous heat treatment heats); or if there are requirements for batch weight, this shall be determined through negotiation between the supplier and the purchaser and noted in the order sheet (or contract).

7.6 Judgment of test results

7.6.1 Chemical composition When the chemical composition of any specimen fails, if the product can distinguish the melting order, the melting order represented by the sample will be deemed to be unqualified. Other melts are inspected in sequence. Delivery to those who pass the test. If the melting times cannot be distinguished, the batch will be deemed unqualified.

7.6.2 Size deviation When the size deviation of any plate fails, the supplier is allowed to inspect the finished products one by one. Delivery to those who pass the test. If the size deviation of any sheet and strip fails, the roll will be deemed unqualified.

7.6.3 Covering rate If the covering rate of any specimen fails, double the number of specimens shall be taken from the batch of products for repeated testing. If all repeated test results are qualified, the batch of products will be deemed qualified. If the repeated test results are still unqualified, the product represented by the specimen will be deemed to be unqualified. Suppliers are allowed to inspect finished products piece by piece (roll). Delivery to those who pass the test.

7.6.4 Tensile mechanical properties, compression properties, impact toughness, bending properties, fatigue properties, residual stress, stress corrosion resistance, exfoliation corrosion resistance, intergranular corrosion sensitivity

7.6.4.1 When any specimen fails to pass the test, the product of this batch (or heat treatment heat) will be deemed to be unqualified or shall be subject to 7.6.4.2.

7.6.4.2 If the heat treatment heat of the product can be distinguished, double the number of specimens shall be taken from the heat treatment heat represented by the specimen for repeated testing. If the heat treatment heats cannot be distinguished, double the number of specimens shall be taken from the batch of products for repeated testing (including products represented by unqualified samples taken for the first time). If the repeated test results are all qualified, the product of this batch (or heat treatment heat) will be deemed qualified. If the specimen performance is still unqualified in the repeated test results, the product of this batch (or heat treatment heat) will be deemed to be unqualified. Upon agreement between the supplier and the purchaser, the supplier is allowed to inspect the finished products sheet by sheet (roll). Delivery to qualified candidates may be carried out according to 7.6.4.3.

7.6.4.3 After repeated heat treatment, the supplier shall inspect all exit-factory inspection items in Table 10 according to the heat, except chemical composition, size deviation, coating layer and appearance quality. The sampling quantity is according to Table

11.When all inspection results are qualified, the batch of products is deemed to be qualified; otherwise, the batch of products is deemed to be unqualified.

7.6.5 Fracture toughness

7.6.5.1 If the plane strain fracture toughness KIc value of any specimen fails or the "batch release KQ" value does not meet the requirements, the product of this batch (or heat treatment heat) will be judged to be unqualified or shall be implemented according to 7.6.4.2.

7.6.5.2 If the plane stress fracture toughness of any sample fails, the product of this batch (or heat treatment heat) shall be deemed to be unqualified or shall be implemented in accordance with 7.6.4.2.

7.6.6 Conductivity

7.6.6.1 When the conductivity of any specimen blank fails to meet the standard, proceed according to 7.6.4.2.

7.6.6.2 If the conductivity uniformity of any product fails, the batch will be deemed unqualified.

7.6.7 Matching relationship between electrical conductivity and mechanical properties When the matching relationship between the electrical conductivity and mechanical properties of any specimen blank is unqualified, the judgment shall be based on the stress corrosion resistance test results.

7.6.8 Ultrasonic flaw detection acceptance level If the ultrasonic flaw detection acceptance level of any plate fails, the finished product will be deemed unqualified.

7.6.9 Macrostructure When the macrostructure of any sample fails, the judgment shall be as follows:

a) If the product fails due to cracks or delamination defects, the supplier can inspect the finished products one by one. Delivery to those who pass the inspection;

b) When the grain size level and fracture structure of any specimen are unqualified, if the melting order can be distinguished, the melting order will be deemed to be unqualified. Other melts are inspected in sequence. Delivery those who pass the inspection. If the melting times cannot be distinguished, the batch will be deemed unqualified.

7.6.10 Microstructure If the microstructure of any specimen fails, the batch (or heat treatment heat) is deemed to be unqualified.

7.6.11 Appearance quality If the appearance quality of any product fails, the finished product sheet (roll) will be deemed to be unqualified.

8.1 Marks

8.2 Packaging, transportation, storage The plates are packed with padding paper. When the purchaser requires not to use paper, oil paper or film, it shall be clearly stated in the order sheet (or contract). Others shall be carried out according to the provisions of GB/T 3199.When the purchaser needs sheets and strips with sleeves, he shall indicate the sleeve material in the order sheet (or contract).

8.3 Quality certificate Each batch of products shall be accompanied by a product quality certificate stating.

a) Name of supplier;

b) Product name;

c) Designation, condition and size specifications;

d) Product batch number;

e) Net weight or number of boxes (sheets) and rolls;

f) Reference to this document;

g) Various analysis and inspection results and inspection stamps from the supplier's quality inspection department;

h) Packaging date (or exit-factory date).