What Is Tear Test?
The tear test is a test in which the force or energy required for a tear to propagate from a pre-cut notch in the specimen is measured. The Elmendorf pendulum method and the trapezoid method are common.
Purpose of Tear Test
The purpose is to assess the risk that small damage occurring during use will grow and lead to loss of function.
Which Products Is Tear Test Applied To?
- Plastic film and packaging
- Paper and cardboard
- Woven and nonwoven fabric
- Coated textile and membrane
In Which Sectors Is Tear Test Used?
Standards Related to Tear Test
- ISO 6383-1
- ISO 6383-2
- ISO 13937-1
- ISO 13937-2
- ASTM D1922
- ISO 1974
Tear Test Conditions
- Method
- Elmendorf pendulum or trapezoid tear
- Notch
- A pre-notch of the length defined in the standard is cut
- Environment
- Conditioning at 23 °C / 50% relative humidity
- Orientation
- The machine direction and cross direction are measured separately
Equipment for Tear Test
- Elmendorf tear tester
- Universal testing machine (trapezoid method)
- Notch-cutting rig
- Conditioning room
Sample Requirements for Tear Test
- Specimen size is cut per the relevant standard
- The pre-notch must be exactly the length defined in the standard
- Generally at least five specimens per direction
- Conditioning is mandatory
Duration of Tear Test
Duration per measurement is short; conditioning typically takes 24 hours.
Tear Test Procedure
- 1Specimens are cut to the size defined in the standard and conditioned.
- 2The pre-notch is cut.
- 3The specimen is placed in the machine.
- 4The pendulum is released, or tension is applied in the trapezoid arrangement.
- 5Tear force or energy is recorded; the average is taken for each direction.
Tear Test Acceptance Criteria
The acceptance criterion is given in the product standard as a minimum tear resistance per direction.
Evaluation of Results
Machine-direction and cross-direction results are reported separately; in anisotropic materials these two values can differ significantly.
Tear Test Report
- Standard and method applied
- Specimen direction and dimensions
- Notch length
- Tear resistance by direction and the average
- Conditioning conditions
Accreditation
EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.
Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.
Scope and authorisationsRelated Regulations
- Packaging and textile product standards
Mekanik Testler — What Does This Testing Field Cover?
The section below describes the field that the Tear Test test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.
Mechanical testing measures how a material or a part behaves under force. The family ranges from static loading (tension, compression, bending) to time-dependent behaviour (fatigue, creep), and from hardness and wear to fracture toughness.
What these tests have in common is that the result is reported as a MATERIAL PROPERTY. Yield strength or hardness is not a conformity decision; it is numerical data against which the design and the product standard will compare. Mechanical test reports are therefore usually an input to an engineering decision rather than to a product approval — material selection, safety factor, life prediction.
The distinction between static and dynamic behaviour is the key to understanding the field. A part may appear entirely unstressed under a static load yet break under repeated loading; fatigue fracture occurs at stresses well below the yield strength and gives no warning. For rotating, vibrating or cyclically loaded parts, a tensile test alone is therefore not sufficient evidence.
Test conditions determine the result, and this is critical for the readability of the report: specimen geometry, loading rate, temperature, conditioning and the gripping arrangement. The same material gives different values under different conditions. In plastics the rate effect is very pronounced, in metals the temperature effect; in composites the specimen orientation changes the result entirely.
Hardness is the most misused measurement in the field. Because it is fast, close to non-destructive and inexpensive, it is often used in place of strength. Conversion tables from hardness to strength exist, but they are APPROXIMATE and depend on the material group; using them as the sole evidence in material acceptance is wrong.
The fracture mechanics side requires a specific competence. Fracture toughness and fatigue crack growth rate measurements make it possible to calculate how long a cracked structure will last; they are the basis of damage-tolerant design in fields such as pressure equipment, aircraft structures and pipelines.
Method groups in this field
Static tests
Tension, compression, bending, shear and torsion. Yield and tensile strength, elongation and modulus of elasticity are obtained.
Impact tests
Charpy and Izod notch impact; the brittle-to-ductile transition behaviour of the material is determined as a function of temperature.
Hardness
Brinell, Vickers, Rockwell, Shore and micro hardness. Valuable for surface treatment depth and local differences in strength.
Fatigue
Force- and strain-controlled axial fatigue, fatigue in bending; S-N curves and the endurance limit.
Creep and stress relaxation
Behaviour under long-term load at high temperature; decisive for boiler, turbine and pressure equipment materials.
Fracture mechanics
Plane-strain fracture toughness, the J integral, CTOD and fatigue crack growth rate.
Wear and friction
Taber and rotating drum abrasion, coefficient of friction measurements.
Commonly confused in this field
- Calculating strength from hardness is approximate; it cannot be used as the sole evidence in material acceptance.
- Adequate static strength does not demonstrate fatigue strength; a cyclically loaded part requires a separate test.
- If test rate and temperature are not reported, the result cannot be compared — especially for polymers and composites.
- A test specimen and the actual part may not give the same value; moulding orientation, weld lines and differences in surface treatment all have an effect.
- A strength value given for a composite without stating the specimen orientation is meaningless.
- ASTM and ISO counterparts measure the same quantity but use different specimen geometries; the results are not treated as directly equivalent.
Which decisions these results support
- Design verification and material selection
- Incoming material control and supplier approval
- Meeting the mechanical requirements of the product standard
- Failure analysis, life prediction and damage tolerance calculation
- Verifying heat treatment and surface treatment processes
Related Tests
Frequently Asked Questions About Tear Test
Why are the machine direction and cross direction tested separately?
In films and fabrics, molecular or yarn orientation differs along the production direction. Tear resistance therefore varies markedly with direction, and the two values are reported together.