ASTM D3039 Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials

EUROLAB laboratory provides testing and compliance services within the scope of ASTM D3039 standard. The ASTM D3039 standard is a widely used test standard for determining the tensile properties of composite materials. Due to its lightweight properties and high tensile strength, composite materials are increasingly preferred by aerospace and automotive. It is used to replace metals in industries and many applications.

The ASTM D3039 test is performed by applying a tensile force to a sample (coupon) and measuring the various properties of the sample under stress. It is performed on a universal testing machine (also called a tensile testing machine) and combines both inch-pounds and SI units into a single standard.

ASTM D3039 measures the following tensile properties:

• Tensile strength: maximum stress applied during testing (usually stress at break)
• Ultimate tensile stress - stress at break
• Tensile modulus: how much the material can deform (flex) in response to stress.
• Poisson's ratio: the rate of change in transverse and longitudinal strain between two longitudinal strain points (the same points usually used for modulus determination, i.e. 0,1% to 0,3%)
• Transition strain: where the material exhibits a yielding behavior (represented as a change in slope in the stress-strain response), the transition strain is the strain value at which the change in slope occurs.
• Fault mode: Broken samples should be inspected and the type, area and location of the fault recorded via a three-character code.

Additionally, ASTM D3039 is used as a quality control tool for composite fiber coating applications. In these applications, composite coatings are applied and cured in situ to concrete columns for seismic reinforcement. The composite tensile test provides evidence that the material has been laid and cured according to the manufacturer's instructions.

To ensure an accurate determination of the composite tensile strength, the measuring area must have a nearly even stress distribution. The use of end claws helps to deliver the load smoothly from the jaws to the sample. Tabs are not always necessary or even desirable. With carefully aligned hydraulic grips and a suitable gripping surface, woven composites, 90 degree tape and +/- 45 degree placements can be tested more effectively without tabs. Zero degree tape lamina specimens are best tested with tapered nails. Regardless of the type of claw used, the test machine jaws should extend past the end of the sample claws.

Test machine grip alignment is also critical to obtaining accurate results with ASTM D3039 testing. Generally hydraulically loaded grips are used. The alignment of the jaws is adjusted and verified with a 9-strain gauge rod to ensure that the loading is fully tensile without bending.

Strain can be measured with a calibrated extensometer or strain gauge. The module is mostly calculated between 1000 and 6000 micro voltage. Biaxial strain measurements are used to obtain the Poisson ratio. The entire load sequence can be heated or cooled in an environmental chamber so that the tensile properties can be characterized from cryogenic temperatures to the degradation temperature of the material.

This standard does not purport to address all, if any, safety concerns associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory restrictions prior to use.

Our organization, EUROLAB, provides standard test method services for the tensile properties of polymer matrix composite materials, within the framework of national and international standards, with its trained and expert staff and advanced technological equipment, among numerous test, measurement, analysis and evaluation studies. Provides testing services within the scope of ASTM D3039 standard.