Plastic film · Laboratory data reduction
Plastic Film Tensile Strength & Elongation Calculator
Reduce thin plastic film tensile force, width, thickness, gauge length, and extension to tensile strength and elongation at break.
Formula and method
Original cross-section (mm²) = width (mm) × thickness (µm) ÷ 1,000. Tensile strength (MPa) = maximum force (N) ÷ original cross-section (mm²). Elongation (%) = extension at break ÷ initial gauge length × 100.
Inputs and units
Enter the specimen width and average thickness represented by the test strip, the initial gauge length, maximum tensile force, and extension at break. Keep machine direction or transverse direction, specimen type, test speed, conditioning, grip separation, and failure location with the record.
Worked example
A 15 mm-wide, 50 µm-thick strip with 50 mm gauge length, 30 N maximum force, and 40 mm extension gives 40 MPa tensile strength and 80% elongation.
When to use it
Use after a thin-film tensile pull to check data reduction, normalize force for specimen section, or compare repeated specimens on one documented test basis.
How to interpret the result
MPa is numerically equal to N/mm². Compare results only within the same material direction, specimen geometry, conditioning, strain-rate, gripping, and result definition. Keep individual replicates and failure observations.
Assumptions and limitations
This arithmetic does not correct for thickness variation, grip slippage, breaks at the jaw, preload, machine compliance, strain measurement method, anisotropy, or yield-versus-break definitions. It does not determine conformance.
Validation guidance
Verify width and thickness with calibrated devices, confirm the gauge basis used by the extension channel, reject or flag invalid break locations under the governing procedure, and independently reproduce one specimen calculation.
FAQ
Can I compare machine-direction and transverse-direction results directly?
Treat them as separate populations. Film orientation often makes direction a primary part of the test identity.