What is ASTM D695?
ASTM D695 is a standard specification established by ASTM International, which describes the method for conducting compression tests on rigid plastics. This standard is widely used by manufacturers and researchers to measure the compressive properties including modulus, yield strength, and compressive strength.
Why is ASTM D695 Important?
Compression testing under ASTM D695 provides critical data that is essential for several reasons:
Specimen Preparation
For ASTM D695, the test specimens are typically cylindrical with a diameter of 12.7 mm (0.5 inches) and a height of 25.4 mm (1 inch). These specimens can be machined from larger pieces or molded directly to size. Ensuring the correct dimensions and surface smoothness is crucial for accurate testing.
Testing Procedure
The test involves placing a plastic specimen between two plates of a compression testing machine and applying a load until the specimen fails or deforms to a specific degree. The force applied and the deformation of the specimen are recorded, from which the compressive strength and modulus can be calculated.
Analysis and Interpretation
The key outcomes from the compression test include: