This test method is well suited for testing very thin composites in compression. It requires 2 specimens, one tabbed with a very small gage section to determine strength and a second specimen that is untabbed and strain gaged to determine modulus. Because of its small size; specimens are 0.5 inch wide by 3.188 inch long; this test method is also well suited for non-ambient testing in very cold and extreme heat environments.
This is a very common test method for the determination of flexural performance of a composite material. It can accommodate a wide range of specimen sizes and configurations. thus making it a excellent choice for structural performance testing. While a tensile and a compressive component can be observed in this test, it is not advised to use these values for design criteria in place of actual tensile and compressive tests.
D3039 is one of the most widely used test methods. It is the general guideline by which tensile strength and performance is based. Depending on the material type-be it unidirectional carbon/epoxy or woven glass/urethane, this method provides the guide to testing most material systems. Specimens are generally 10-12 inches long, from 0.5 to 1.0 inch wide, straight-sided and can be tested with or without end tabs. Extensive study at the CMRG has provided expertise in the testing and evaluation of tensile specimens. Refer to SAMPE proceedings from the 1999 and 2000 Spring Symposium to read the studies that were performed here concerning tensile testing.
Another tried and true test method, D3410 gives a complete description of 2 compression fixtures, namely the Celanese fixture and the IITRI fixture. The Celanese fixture is rarely used these days, however the IITRI fixture is still used extensively for quality compression strength and performance.
Five multi-station dead weight tensile creep testing facilities are available at the CMRG. These creep frames can test 20 full-size D3039 tensile specimens simultaneously in a variety of environmental conditions. The entire frame can be subjected to the same environment with various load levels applied to the specimens. Or, independent environmental conditions can be applied to individual specimens, again with similar or unique load levels. These frames are very versatile and can yield a complete set of data for a creep profile, including modulus decay and strain to failure.
Two multi-station flexural creep test apparatus are available at the CMRG. These frames can test 135 flexural specimens simultaneously. The frames are divided into sections of 45 specimens each, thus allowing for the individual environmental conditioning of a group of specimens. Discrete loads can be placed on each specimen and modulus decay can be monitored throughout the duration of the testing.
The CMRG also has developed a one-of-a-kind universal creep testing facility that can test up to 8 specimens independently at various temperature- and load-time profiles.
Not only can the CMRG perform a myriad of tests at room temperature we also have a wide temperature over which we can test. Using a furnace, we can achieve temperatures in excess of 1000ºC. Flex tests are best suited for use in this chamber due to the small internal area of the furnace.