ISO 8307:2018 pdf free
ISO 8307:2018 pdf free.Flexible cellular polymeric materials – Determination of resilience by ball rebound
The test pieces shall consist of the entire product sample or a suitable portion of it, except that in no case shall the thickness be less than 50 mm or the area less than 100 mm × 100 mm. Test pieces less than 50 mm thick shall be plied up, without the use of cement, to a minimum of 50 mm. For moulded products, the top skin shall be removed.
Thicker test pieces can be used to avoid spurious results, which can occur with very soft materials due to the influence of the baseplate.
NOTE The minimum test piece thickness of 50 mm cannot be sufficient for very soft materials: if spurious results are obtained, a thicker test piece can be used. Very low density materials can also cause problems due to rebound of the test piece itself. With multiple-ply test pieces, slipping can occur between the plies. This problem can be overcome by using the largest possible area of the test piece.
Three test pieces per sample shall be tested. The three test pieces may be obtained by using separate items or different locations on a given item.
Material shall be tested not less than 72 h after manufacture, unless, at either 16 h or 48 h after manufacture, it can be demonstrated that the mean rebound resilience values obtained do not differ by more than±10 % from those obtained after 72 h. Testing is permitted at either 16 h or 48 h if, at the selected time, the above criterion has been satisfied.
Prior to the test, the test pieces shall be conditioned undeflected and undistorted for at least 16 h in one of the following atmospheres as given in ISO 23529:
一23 °C±2°C, (50±5) % relative humidity;
一27 °C±2 °C, (65±5) % relative humidity.
This period can form the latter part of the period following manufacture.
In the case of quality-control tests, test pieces can be taken a shorter time (down to a minimum of 12 h) after manufacture and testing carried out after conditioning for a shorter period (down to a minimum of 6 h) in one of the atmospheres specified above.ISO 8307 pdf download.
