GB/T 3903.13-2020 in English

Background of Standard Revision and Technological Evolution

This standard replaces GB/T3903.13-2005 version. The main technical changes are reflected in:

Detailed explanation of core test methods

Equipment requirements

Key equipment includes: drying oven (70℃±2℃), thickness gauge (10kPa±3kPa) and measuring tools (accuracy±0.2mm).

Operational procedures

1. Sampling according to ISO17709, ISO18454 environmental conditioning ≥24h
2. Make a reference incision with a spacing of 100mm/50mm (depth ≤0.5mm)
3. Constant temperature treatment at 70℃ for 24h±0.5h
4. Measure the deformation after cooling for 30 minutes

Result calculation and judgment

Calculation formula: S=(L-L0)/L0×100%

• L0: initial incision distance (mm)
• L: incision distance after treatment (mm)

Take the data with the largest absolute value among the three samples as the final result, and note the shrinkage/elongation status.

Implementation suggestions

Precautions

• The sample needs to be flattened for measurement when it is curled
• Measurement is taken at the center point when the incision becomes wider
• Thickness measurement is in accordance with ISO23529 requirements