ISO 604 Plastics - Test Standard for Determination of Pressure Properties

The ISO 604 standard, developed by the International Standards Organization (ISO), specifies a method for determining the compressive properties of plastics under defined conditions. A standard test specimen is defined, but its length can be adjusted to prevent bending under load from affecting the results. A range of test rates are included.

This method is used to investigate the compressive behavior of test specimens and determine compressive strength, compressive modulus, and other aspects of the compressive strain/strain relationship under defined conditions.

The ISO 604 standard applies to the following materials:

• In addition to unfilled types, including filled and reinforced compounds with rigid and semi-rigid thermoplastic molding and extrusion materials, for example, short fibers, small rods, plates or granules; rigid and semi-rigid thermoplastic sheet,
• Rigid and semi-rigid thermoset molding materials, including filled and reinforced compounds; rigid and semi-rigid thermoset sheet,
• Thermotropic liquid-crystal polymers.

This International Standard with ISO 10350-1 and ISO 10350-2 applies to fiber-reinforced compounds with fiber lengths ≤ 7,5 mm before processing.

The method is not normally suitable for use with materials reinforced by textile fibers, fiber-reinforced plastic composites and laminates, rigid cellular materials or sandwich structures containing cellular material or rubber.

The method is performed using specimens that can be molded to selected dimensions, machined from the middle of a standard multipurpose test specimen, or molded or machined from finished or semi-finished products such as extruded or cast sheet.

The method specifies the preferred dimensions for the test specimen. Testing on samples of different sizes or samples prepared under different conditions may produce incomparable results. Other factors such as test speed and conditioning of samples can also affect results. Consequently, when comparable data are required, these factors should be carefully checked and recorded.

Among the services provided by our organization within the framework of material testing services, there are also ISO 604 standard tests.