ISO 1924-2 — Tensile properties of paper and board (20 mm/min)

ISO 1924-2: Paper and board — Determination of tensile properties — Part 2: Constant rate of elongation method (20 mm/min)

ISO 1924-2 specifies a laboratory procedure for determining tensile properties of paper and board using a tensile testing machine operated at a constant crosshead (elongation) speed of 20 mm/min. The method always includes tensile strength and can also support additional calculated properties when agreed between parties.

This standard also addresses calculation of commonly reported normalized results (such as tensile index) and related energy/elastic-response metrics based on the recorded force/elongation behavior and supporting sheet property data.

Quick definition

ISO 1924-2 is a constant-rate-of-elongation (20 mm/min) tensile test method for paper and board used to measure tensile strength and, when required, strain at break and tensile energy absorption (plus related indices/calculations).

What this standard covers

ISO 1924-2 focuses on tensile performance of paper and board test pieces pulled in tension until rupture at a defined elongation rate. It is applicable to a broad range of paper and board grades provided the selected load range and elongation capacity of the instrument are suitable.

The scope includes paper and board generally and can be used for components of corrugated board (for example, liner and medium), while excluding corrugated board as a combined structure. Tissue and tissue products are typically handled under tissue-specific tensile references rather than this method.

Why this standard matters in testing

Tensile results for paper are sensitive to test rate and to how the specimen is clamped and aligned. ISO 1924-2 is commonly specified to standardize those variables so buyers, mills, converters, and third-party laboratories can compare tensile performance using the same elongation-rate basis (20 mm/min).

In practice, ISO 1924-2 data is often used for incoming material verification, in-process monitoring, release testing, supplier qualification, and troubleshooting issues like web breaks, converting defects, or inconsistent strength in the machine direction (MD) or cross direction (CD).

Common materials, product types, or applications covered

ISO 1924-2 is commonly applied to printing and writing papers, packaging papers, paperboard grades, and corrugated components (liners and fluting/medium). It is also used in lab settings to compare grade changes, furnish/process adjustments, or coating/lamination impacts where tensile response is a key acceptance metric.

Typical outputs used by industry: Tensile strength (force per unit width), strain (or stretch) at break, tensile energy absorption (TEA), and normalized indices (for example tensile index) when grammage is part of the reporting basis.

Common test or verification workflow

A typical ISO 1924-2 workflow starts with representative sampling and conditioning of specimens to a specified laboratory atmosphere, followed by cutting test strips in MD and/or CD as required by the purchase specification. The specimen is clamped in opposing grips, aligned to avoid slippage and jaw breaks, and pulled to rupture at a constant elongation speed of 20 mm/min while force (and optionally elongation) is recorded.

Depending on the reporting requirements, results may include only tensile strength or may also include strain at break, tensile energy absorption, modulus-related calculations, and normalized indices that rely on additional sheet properties (commonly grammage and sometimes thickness).

Equipment commonly used for this standard

ISO 1924-2 is typically run on a universal testing machine (UTM) or dedicated paper tensile tester capable of maintaining a constant rate of elongation of 20 mm/min and recording peak force reliably through rupture.

• Tensile frame / controller: UTM or paper tensile tester with stable speed control at 20 mm/min and appropriate data acquisition.
• Load measurement: Load cell sized to expected peak forces for the grade range (to maintain accuracy and resolution).
• Grips/clamps for paper: Pneumatic or mechanical paper grips designed to reduce slippage and jaw breaks; grip face material and pressure control are often critical to repeatability.
• Elongation measurement (when required): Crosshead displacement and/or an extensometer approach suitable for thin sheet materials, depending on the properties being reported.
• Specimen preparation accessories: Strip cutters and templates appropriate for paper tensile strips, plus conditioning control consistent with the referenced atmosphere.

Equipment-selection caution: Because tensile results are rate-dependent and sensitive to gripping, it is important that the quoted setup matches the cited part and speed (ISO 1924-2 at 20 mm/min) and the customer’s required outputs (strength-only vs. energy/strain/modulus calculations).

How to read this designation or revision

ISO 1924-2 identifies Part 2 of the ISO 1924 tensile-properties series for paper and board. The “Part 2” method is defined by the constant rate of elongation of 20 mm/min; other parts in the series may use different speeds and can produce different results.

Year/edition matters: When a requirement references ISO 1924-2 with a year (for example “ISO 1924-2:2008”), testing conditions, calculation details, and reporting expectations should be aligned to that exact edition. ISO also maintains drafts during revision cycles; procurement and compliance language usually requires the published edition unless a contract explicitly calls for draft content.

Related standards, methods, or frameworks when useful

ISO 1924-2 is commonly used alongside standards that define sampling, conditioning atmosphere, and supporting sheet property measurements used for normalized reporting. The ISO 1924 series also includes an alternative constant-rate-of-elongation method at a different speed (Part 3), which should not be treated as interchangeable with Part 2 unless explicitly permitted by the customer specification.

Practical note: If your customer documentation references multiple paper test methods (for example tensile plus grammage and thickness), instrument scope may need to include both the tensile frame and the supporting measurement tools or procedures needed for the required calculated indices.

Get a quotation for an ISO 1924-2 tensile test setup

If you are specifying a UTM or dedicated paper tensile tester for ISO 1924-2 (20 mm/min), we can help match capacity, grip style, and data outputs to the grades you run and the way your lab reports results. For pricing and configuration options, you can request a detailed quote.