Fabric Bursting Strength Testing
category
Bursting strength testing measures the resistance of fabric to multi-directional (biaxial) stress by applying hydraulic or pneumatic pressure to a clamped circular fabric specimen until it ruptures — a test more representative of actual in-use failure modes for knitted, nonwoven, and 3D-woven fabrics than uniaxial tensile testing. ISO 13938-1 (hydraulic method, Mullen burst tester, SDL Atlas M021A): circular specimen clamped over 30.5 mm diameter aperture, hydraulic pressure applied at 170 mL/min until fabric bursts — measures burst pressure (kPa) and burst distension (mm, dome height at failure). ISO 13938-2 (ball burst method, steel ball 25 mm diameter pushed through 30 mm aperture specimen at 100 mm/min CRE tester — measures peak force in N). Specification minimums: single jersey knitwear (200 g/m²): hydraulic burst ≥ 300 kPa; technical filter fabric (150 g/m² woven PET): ≥ 500 kPa; surgical nonwoven (SMS 40 g/m²): ≥ 20 kPa; geotextile nonwoven (300 g/m²): CBR puncture resistance ≥ 2,500 N (ISO 12236, 50 mm diameter piston, similar principle to ball burst). Relationship between burst and tensile: burst strength (kPa) ≈ tensile strength (N) / (aperture radius × π) for isotropic fabrics — anisotropic woven fabrics burst in bias direction where neither warp nor weft yarn systems are fully loaded. Hydraulic burst versus ball burst: hydraulic measures fabric material failure; ball burst measures combined fabric + puncture resistance (geometry dependent) — ball burst preferred for protective textile applications simulating sharp object impact.
Role
Bursting strength testing provides the biaxial mechanical performance characterisation essential for knitted, nonwoven, and technical fabric applications where multi-directional stress loading in use (elbow joints in knitwear, filter media under pressure, geomembrane under soil overburden) makes uniaxial tensile testing mechanistically inadequate for predicting real failure modes.