ASTM D828 - Standard Test Method for Tensile Properties of Paper and Paperboard Using Constant-Rate-of-Elongation Apparatus

ASTM D828

Standard Test Method for Tensile Properties of Paper and Paperboard Using Constant-Rate-of-Elongation Apparatus

This test method covers procedures for determining tensile properties of paper and paperboard.

What is ASTM D828?

ASTM D828 is a standard test method developed by ASTM International that outlines procedures for determining the tensile properties of paper and paperboard. These properties include tensile strength, tensile energy absorption (TEA), stretch, and tensile stiffness. This standard is vital for evaluating the mechanical behavior of paper materials under tensile loading, offering a consistent method to assess the quality and performance of various paper products, such as packaging materials, tissue, and specialty papers. Industries that rely heavily on paper products use ASTM D828 to ensure that materials meet specific tensile property criteria for functionality and durability.

Determining Tensile Properties of Paper and Paperboard

Tensile properties such as tensile strength, elongation, and modulus are critical indicators of the performance of paper and paperboard under stress. Tensile strength measures the maximum force a sample can withstand before failure, while elongation assesses the extent of stretching a material can endure before breaking. Additionally, tensile stiffness is determined to evaluate the rigidity of the material under tension. These properties provide essential insights into how a paper product will behave during manufacturing, processing, and end-use, ensuring its suitability for applications requiring mechanical strength, such as packaging or printing substrates.

ASTM D828 Test Process

The ASTM D828 test procedure involves the use of a tensile testing machine, which applies controlled tensile forces to a sample of paper or paperboard. The sample is clamped between two grips, with one grip being stationary and the other moving at a constant rate of extension. The load applied and the elongation of the sample are continuously measured until the material fails. Key parameters like the initial grip separation, test speed, and environmental conditions are strictly defined by ASTM D828 to ensure repeatability and accuracy of results. The output typically includes stress-strain curves that help to characterize the mechanical properties of the paper or paperboard under investigation.

The standard also provides guidelines for sample preparation, ensuring uniformity in thickness, moisture content, and conditioning of the test materials. By following these protocols, manufacturers can obtain reliable data to evaluate the structural integrity and functionality of their paper products.