BS EN ISO 6383-1 specifies a method for determining the tear resistance of plastic film or sheets less than 1 mm thick. Specimens may be pre-conditioned at a defined temperature and humidity. This method is not suitable for brittle or highly extensible materials.

Test Summary

The test can be used to compare the propagation resistance of various plastic films and sheeting of comparable thickness. Standard sized specimens are separated by a slit of half the length of the sample resulting in two “legs” which are torn apart at a constant speed while the tensile force is measured.

Test Procedure

Samples may be pre-conditioned if required, and are cut to a defined shape with two “trouser legs” of 25 mm each. Where the test material exhibits different properties depending upon which direction the specimens are cut from (anisotropy), two groups of sample should be prepared with their major axis parallel to, and perpendicular to the direction of the feature giving rise to the observed difference. The legs of the specimen are held in opposed grips on the tensile testing stand, and separated at a constant speed of 200 or 250 mm/min. As the sample is torn, the tensile force is recorded. The average load is calculated, disregarding the first and last part of the force/distance curve. A minimum of five specimens in each direction are required.

Test Apparatus

• Die cutter or cutting apparatus.
• Micrometer reading to 0.0025 mm
• Force testing stand
• Suitable range loadcell compatible with the force testing stand.

Preparation

Where conditioning is required, test specimens are stored in accordance with ISO 291.

Method

• 1. If required, pre-condition the samples as specified in ISO 291.
• 2. At least five samples are required.
• 3. Specimens are cut, ideally using a die cutter. Sample may be cut in the longitudinal or transverse direction of the sample
• 4. The thickness of the specimen is accurately measured in mm in several points, and an average value (d) calculated.
• 5. Specimens are clamped with one “leg” in each of the grips of the force testing stand which are initially set 75 mm apart.
• 6. The test stand is set in motion at a fixed crosshead speed of 200 or 250 mm/min.
• 7. Continue the test until the tear has propagated through the entire length of the entire unslit length of the sample.
• 8. Measure the mean load (Ft) over a 50 mm interval of the tear disregarding the first 20 mm and final 5mm portions of the force/distance curve.
• 9. Calculate the Tear resistance from the formula

Tear resistance = Ft/d - report as newtons/mm

Report

The test report shall contain:

• All the information necessary for the complete identification of the sample including direction if appropriate and standards atmosphere used for pre-conditioning if appropriate.
• The test speed used
• The average thickness of each specimen.
• Report the arithmetic mean of at least five samples from each set of test specimens, in newtons/mm

Mecmesin Test Equipment Required for {Test Standard}

• FPT-H1 Horizontal Friction Peel Tear Tester
• Alternative motorised test stand – MultiTest 2.5-i
• Suitable range loadcell for the test stand
• Lightweight grips
• Emperor software

Link to relevant web pages.

Please refer to the latest official BS ISO EN Standard for more detailed information. This overview is intended to provide a basic understanding of the test procedure and suitable equipment to meet the standard