ISO 527-3 is an ISO standard that specifies test conditions for determining the tensile properties of plastic films and sheets with a thickness less than 1 mm, using the general principles in ISO 527-1.
If you need help matching grips, extensometry, or control software settings to the edition your customer or internal spec calls out, talk with our team about your film/sheet material and reporting requirements.
ISO 527-3: Plastics — Determination of tensile properties — Part 3: Test conditions for films and sheets
ISO 527-3 is part of the ISO 527 series for tensile testing of plastics. This part focuses on the test conditions that apply specifically to thin film and sheet materials (less than 1 mm thick).
It is commonly used for tensile characterization and quality control of polymer films and thin sheeting where consistent conditioning, specimen handling, and test setup are critical to repeatable results.
Quick Definition
ISO 527-3 defines the test conditions used to measure tensile properties of plastic films and sheets under 1 mm thick, building on the general tensile testing framework in ISO 527-1.
What This Standard Covers
This standard is focused on tensile testing for thin plastics where specimen thickness, gripping, and strain measurement can significantly influence results.
- Plastic films and plastic sheets less than 1 mm thick.
- Use of ISO 527-1 as the baseline for general tensile testing principles and definitions.
- A boundary between thin film/sheet testing (this document) and thicker sheet testing (ISO 527-2 is typically used for plastics above 1 mm).
ISO 527-3 is not normally considered suitable for cellular materials or plastics reinforced by textile fibres, because these materials often require different specimen handling and/or different test approaches.
Why This Standard Matters in Testing
For films and thin sheets, small changes in gripping pressure, alignment, thickness measurement, or strain measurement method can shift tensile results. ISO 527-3 helps labs and manufacturers apply consistent test conditions so tensile properties can be compared across lots, suppliers, and manufacturing lines.
In procurement and product qualification workflows, ISO 527-3 test results are often used to support material selection, supplier conformance discussions, and release criteria for film-based products.
Common Materials, Product Types, or Applications Covered
ISO 527-3 is typically applied to thin polymer products where tensile behavior in the machine direction (MD) and transverse direction (TD) may be relevant and where thickness is below 1 mm.
- Packaging films and laminates
- Protective films and functional barrier films
- Extruded or calendered thin sheeting
- Battery separator and technical films (application-dependent)
Because film products can be highly process-dependent, the exact specimen direction, conditioning expectations, and reporting details are usually driven by the cited ISO 527-3 edition plus any customer or internal material specification.
Common Test or Verification Workflow
ISO 527-3 is commonly used as part of a tensile testing workflow for thin plastics, with ISO 527-1 providing the broader test method framework.
Common workflows: Incoming inspection of film lots, ongoing process control, product qualification, comparative testing across formulations or processing conditions.
Typical outputs: Tensile stress/strain behavior and related tensile properties reported in ISO 527 conventions (often including tensile modulus, tensile strength, and elongation-related properties, depending on the specimen and measurement approach).
Film and thin-sheet testing often benefits from clear agreement on strain measurement approach (crosshead-based vs. extensometry) and on how thickness is measured and averaged, since these choices can affect calculated stress and modulus values.
Equipment Commonly Used for This Standard
ISO 527-3 testing is typically performed on a universal testing machine configured for low-force tensile testing and thin, flexible specimens.
- Universal testing machine (UTM): Electromechanical frame is common for film work; the load capacity and load cell range should fit expected break forces for thin specimens.
- Film/sheet grips: Grips designed to reduce slippage and jaw-induced tearing (selection depends on film type, surface, thickness, and strength).
- Strain measurement: Appropriate extensometry for thin specimens (often non-contact or specialized solutions when contact extensometers could damage the specimen).
- Specimen measurement tools: Thickness measurement equipment suitable for thin film/sheet, with a defined measurement approach and averaging method.
Equipment-selection caution: For thin films, grip face material, jaw alignment, and clamping pressure can be as important as the test frame itself. If you are specifying equipment for a purchasing requirement that cites ISO 527-3, it is worth aligning the grip and strain measurement approach to the exact film type and reporting needs.
How to Read This Designation or Revision
ISO 527-3 identifies Part 3 within the ISO 527 tensile testing series for plastics.
ISO 527-3:2018 indicates the 2018 published edition of this part. In purchase specifications and test reports, the year matters because edition-to-edition changes can affect test condition details and how results are documented.
If a customer drawing or internal SOP references ISO 527-3 without a year, it is usually best practice to clarify which edition is intended before locking a procedure or quoting equipment capability.
Related Standards, Methods, or Frameworks
ISO 527-3 is used alongside other parts of ISO 527 to fully define the tensile testing approach for plastics across thickness ranges.
- ISO 527-1: General principles for determining tensile properties (definitions, general approach, and common requirements).
- ISO 527-2: Commonly referenced for plastics sheets above 1 mm thick (helps avoid misapplying thin-film conditions to thicker materials).
Talk to NextGen about an ISO 527-3 test setup
If you are selecting a UTM, grips, and extensometry for thin films or sheets and need a configuration aligned to ISO 527-3, you can request a detailed quote with your material type, thickness range, and expected force levels.