Scope:

The standard test method for Tension & Elongation of Elastic Fabrics (Constant-Rate-of Extension Type Tensile Testing Machine) by ASTM D4964 is considered satisfactory for acceptance testing of commercial shipments of elastic fabrics like testing loop tension and elongation of elastic fabrics. The use of this ASTM D4964 test method, requires the selection of, or mutual agreement upon, loop tension(s) and elongation(s).

Test Procedure:

ASTM D4964 all specimens get tested in standard atmosphere for testing textiles, which is 21 ± 1 °C (70 ± 2 °F) and 65 ± 2% relative humidity. Specimens are mounted with the seam between the clamps then the specimen is cycled for three times and the loading and extension of the third cycle on the chart is recorded. Remaining specimens are then tested. Band Clamps are required to hold loop specimens during testing according to ASTM D4964. The diameter of the anvils are usually 13.0 ± 0.25 mm (0.5 ± 0.01 in.) or 6.5 ± 0.25 mm (0.25 ± 0.01 in.) and the minimum length of the anvil is 76 mm (3.0 in.).

Specimen Size:

Required size of elastic fibre is cut for the specimen.

Data:

Tension and elongation are reported in SI units or inch pounds and are considered as standard separately. The critical difference is somewhat larger when comparing different fabrics that when comparing samples of fabrics. The loop tension at any % of elongation is to be reported, if requested.