BS ISO 7765-2. Plastics film and sheeting. Determination of impact resistance by the free-falling dart method Part 2. Instrumented puncture test
|Standard number:||21/30429601 DC|
|Status:||Draft for Comment|
This standard 21/30429601 DC BS ISO 7765-2. Plastics film and sheeting. Determination of impact resistance by the free-falling dart method is classified in these ICS categories:
- 83.140.10 Films and sheets
The impact-penetration test described in the two parts of this International Standard is used for the assessment of plastic films and thin sheets (hereinafter referred to as films) under an impact stress applied at right angles to the plane of the film.
Part 1 of this International Standard can be used if it is sufficient to characterize the impact behaviour of the film by an impact-failure energy. Part 2 is used if a force-deformation or a force-time diagram, recorded at practically constant velocity of the striker, is necessary for characterization of the impact behaviour. This applies if:
measured quantities derivable only from this diagram are required or
only a small number of test specimens are available.
The test method is applicable to films of up to 1 mm thickness and makes it possible to compare impact-penetration forces, biaxial deformabilities and energy-absorption capacities of films. Furthermore, if required, the transition region between brittle and tough behaviour of the film under the conditions of testing can be determined by varying the temperature or the penetration velocity or the relative humidity (see also ).
For thicknesses greater than 1 mm, ISO 6603-2 should be used.
The test results are comparable only if the conditions for preparation of specimens, their thickness and surfaces, and the test conditions are identical. Comprehensive evaluation of the reaction to impact stress requires that the determinations are made as functions of deformation rate and temperature for different material variables, such as crystallinity and moisture content.