composites tested to ASTM D6484

ASTM D6484 is a testing standard that measures the open-hole compressive strength of multidirectional polymer matrix composite laminates. Because mechanical fasteners such as rivets, pins, and bolts are commonly used to connect composite laminates, open-hole compressive testing is required in order to determine the ultimate compressive strength of the laminate, the ratio of the specimen across the hole to the diameter of the hole, and the percent bending. ASTM D6484 is relevant to the aerospace industry for the purposes of material specifications, research and development, quality assurance, and structural design and analysis.

Materials Testing System

ASTM D6484 should be run on a well-aligned electromechanical test system such as Instron's 5980 Series with grips and fixtures appropriate to which test procedure is being used. Operators also have the option of using edge-mounted extensometers to measure the displacement.




ASTM D6484 Test Setup
1) 5980 Series Universal Testing System
2) Bluehill Universal Software
3) 2580 Series Load Cell
4) CP113779 Open-Hole Compression Test Fixture
5) 2742-501 Advanced Hydraulic Wedge Grips

 

ASTM D6484 test setup
Grips and Fixtures

There are two different procedures for testing to ASTM D6484. In procedure A, the laminate face is supported in a bolted test fixture. The ends of the fixture are clamped in hydraulic wedge grips, transmitting the force in shear. In Procedure B, compression platens are required to compress the specimen within the test fixture in end loading.

Instron Grips model number 2742-501
300 kN Capacity | 2742-501
Testing Tips and Tricks 
  • During panel fabrication it is critical to have good fiber alignment, since a misalignment could significantly reduce the compressive strength of the laminate.
  • When calculating the ultimate compressive strength of the laminate specimen, use the cross-sectional area of the test coupon without taking the hole into account.
  • To read the full test procedures for this standard, purchase ASTM D6484.