①For steel plates delivered in the heat-treated condition, if the elongation exceeds the specified value in the table by more than 2% (absolute value), the tensile strength may be reduced by 40 MPa from the specified value in the table.
②For steel plates and strips with a thickness greater than 20 mm, for each additional 1 mm of thickness, the elongation after fracture may be reduced by 0.25% (absolute value). The total reduction in elongation for thicknesses not exceeding 32 mm shall not exceed 2% (absolute value), and for thicknesses greater than 32 mm, the total reduction in elongation shall not exceed 3% (absolute value).
③By mutual agreement between the supplier and the buyer, steel with a thickness of not less than 6 mm may be subjected to low-temperature impact tests at 20°C or -20°C. The test temperature and impact absorption energy for other grades shall be agreed upon by both parties.
④Heat treatment refers to normalization, annealing, or high-temperature tempering.