Astm D61821 Pdf |verified|
ASTM D6182-21 establishes a standardized, Bally flexometer-based method for evaluating the flexibility and adhesion of surface coatings on finished leather, specifically detecting cracking, delamination, and discoloration. The test simulates real-world stress on materials for applications like footwear and upholstery, ensuring quality control by simulating continuous flexing. For the full standard, visit ASTM International.
6. Test Conditions and Procedure
- Calibrate testing machine and measuring devices.
- Measure and record specimen dimensions and mass prior to testing.
- Mount specimen in grips ensuring alignment and avoid pre-loading.
- Apply preload (small, defined force) if required to remove slack.
- Test at a constant crosshead speed or strain rate (example: 5 mm/min or 0.01 s−1) until specimen failure or until reaching specified strain.
- Record load vs. displacement (or stress vs. strain) continuously.
- For viscoelastic or creep tests, maintain load/time profiles per Section X.
- Check the "Scope" section first to ensure your specific type of resin is covered.
- Look at the "Apparatus" section to verify you have the correct type of oven and weighing dishes.
- Review the "Safety Hazards" section, as unsaturated polyesters often involve styrene, which requires proper ventilation.
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