ASTM D7192-08a

This test method is designed to provide load versus deformation response of plastic films under essentially multi-axial deformation conditions at impact velocities. This test method further provides a measure of the rate sensitivity of the plastic films to impact.

Multi-axial impact response, while partly dependent on thickness, does not necessarily have a linear correlation with specimen thickness. Therefore, results should be compared only for specimens of essentially the same thickness, unless specific responses versus thickness formulae have been established for the plastic films being tested.

For many plastic films, there may be a specification that requires the use of this test method, but with some procedural modifications that take precedence when adhering to the specification. Therefore, it is advisable to refer to that material specification before using this test method. Table 1 of Classification System D 4000 lists the ASTM materials standards that currently exist.

The values obtained by this test method are highly dependent on the method and conditions of film fabrication as well as the type and grade of resin. Results can vary significantly, depending upon sample quality, uniformity of film gage, die marks, contaminants, and so forth.

1.1 This test method covers the determination of puncture properties of plastic films, over a range of test velocities.

1.1.1 Test Method D 1004 has defined film as having a thickness not greater than 0.25 mm (0.010 in.). Plastic materials having a thickness above this limit are not to be excluded from use unless shown to be rigid (see 3.2.1). Test Method D 3763 is the recommended method for instrumented puncture testing of rigid plastics.

1.2 Test data obtained by this test method is relevant and appropriate for use in engineering design.

1.3 The values stated in SI units are to be regarded as standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Note 1—This test method does not closely conform to ISO 7765-2. The only similarity between the two tests is that they are both instrumented impact tests. The differences in striker, fixture, specimen geometries and in test velocity can produce significantly different test results.